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2 April 2025 A Historical Review of Studies and Conservation Practices for Terrestrial Mammals in the Central and Southern Ryukyu Archipelago in Japan
Fumio Yamada, Masako Izawa
Author Affiliations +
Abstract

We reviewed the history of studies and conservation efforts related to terrestrial mammals in the central and southern Ryukyu Archipelago in Japan, covering six orders, 11 families, 20 species, and six subspecies, with 77% endemic and 62% of species classified as threatened. The most significant feature is that phylogenetically ancient species have survived alongside humans, who have inhabited the islands for approximately 30 000 years. This coexistence is unique to this region and not found in other parts of Japan, making it a globally rare phenomenon. In 2021, four islands in the region were designated as Natural World Heritage Sites, marking a conservation milestone, although challenges remain. Island biodiversity is crucial to global biodiversity because of its high endemism. Island biology provides an essential biogeographical perspective to understand evolution and shape conservation strategies. The region has become a focal point of interest due to its unique biota and distinctive island ecosystems. We concluded that a comprehensive re-evaluation of the islands is essential, focusing on biogeography, ecology, and species interactions. Conservation measures should be tailored to each island by incorporating insights from ethnography, sociology, and economics. It is our responsibility to protect the region's endangered species and the biodiversity for future generations.

Published online 2 April, 2025; Print publication 30 April, 2025

It is estimated that there are approximately 341 000 islands on Earth, with around 22 000 islands larger than 1 km2 and about 319 000 islands smaller than 1 km2, collectively covering a total area of 9 959 553 km2, and making up nearly 7.4% of the Earth's land area (Sayre et al. 2019). These islands comprise oceanic islands (i.e., volcanic islands), atolls, and continental islands (islands on a continental shelf and continental fragments) (i.e., islands that originated from a continental plate but are now isolated from the ocean). These islands are estimated to maintain an 19% of bird species, 17% of rodent species, 17% of flowering plant species, and 27% of human languages (Tershy et al. 2015).

Island biodiversity is immensely important to global biodiversity because of its high endemism of living organisms. Island biology is an important biogeographical approach to understand ecology, evolutionary biology, and a strategy for conservation of biotas on islands surrounded by oceans (Kueffer et al. 2016). It has now been recognized that both historical and ecological biogeographic approaches are necessary to fully understand and explain the pattern of island biodiversity (Feldhamer et al. 2020).

The islands of the Ryukyu Archipelago in Japan, which consist of continental islands from the Eurasian Continent and oceanic islands, are biologically important because of their unique biogeographic history and endemic flora and fauna. Continental islands of the Ryukyu Archipelago were considered to have once been a part of the edge of the Eurasian Continent during Middle Miocene and were later divided into the islands of the Ryukyu Archipelago, consisting of the North Ryukyus, Central Ryukyus, and South Ryukyus, by channels and straits, since the Late Miocene to early Pleistocene (Government of Japan 2019; van der Geer et al. 2021). In the terrestrial mammals, dwarf mammoths, Mammuthus sp. and several deer (e.g., Muntiacus sp., and Cervus sp.) first inhabited the islands of the Ryukyu Archipelago during Pleistocene, and only small mammals, later migrants, have survived to date, such as the spiny rat, Tokudaia spp., the Ryukyu long-furred rat, Diplothrix legata (Thomas, 1906), and the Amami rabbit, Pentalagus furnessi (Stone, 1900), in the Central Ryukyus (van der Geer et al. 2021). Palaeolithic humans and the Ryukyu wild boar, Sus scrofa riukiuanus Kuroda, 1924, arrived on the Central Ryukyus and inhabited the area alongside those mammals present since the latest Pleistocene (37 000–13 000 years ago). During the similar period, the Iriomote cat, Prionailurus bengalensis iriomotensis (Imaizumi, 1967), and the extinct Miyako roe deer, Capreolus tokunagai (Otuka, 1941), the extinct Miyako island rat, Rattus miyakoensis (Kawaguchi et al., 2009), and the reed vole, Microtus fortis (Büchner, 1889), now extinct on the island, arrived on the South Ryukyus (Kawamura et al. 2016; van der Geer et al. 2021). For the unique ecosystems on each island constructed with a complex biogeographic history, the four islands of the Ryukyu Archipelago—Amami-Oshima, Tokunoshima, Okinawa, and Iriomote Islands—were listed as a UNESCO Natural World Heritage Sites in 2021 (UNESCO 2021).

In this review, we aimed to outline the island's history, including human history of the Ryukyu Archipelago, followed by summarizing research, and conservation efforts conducted to date on these islands, utilizing the latest studies and information of native and non-native insular terrestrial mammals. Our focus was particularly on the islands of the “central and southern Ryukyu Archipelago”, which include the Central and South Ryukyus, as well as the Senkaku and Daito Island Groups, excluding the North Ryukyus. The unique mammalian fauna of the central and southern Ryukyu Archipelago is globally distinct and will serve as a specific case study in island biogeography.

Note that the term “Japanese mainland” used in this review refers to the region including Honshu, Kyushu, and Shikoku, but excluding Hokkaido due to historical and zoogeographical differences. The scientific names of terrestrial mammals and other species, including the author and publication year, are primarily presented in the section on the transition of taxonomic nomenclature and in the relevant sections of the review. Additionally, the terminology related to invasion science in this review follows the recent proposal by Soto et al. (2024). Part of this topic was also discussed in Japanese by Izawa and Yamada (2023).

Location of the Ryukyu Archipelago

The Ryukyu Archipelago is situated in a zoogeographical zone that separates the Old North Region from the Oriental Region. The archipelago lies in an oceanic region between the southern end of Kyushu Island in Japan and Taiwan, spanning approximately 1200 km (Fig. 1). It comprises more than 900 islands, including approximately 70 inhabited by humans (Government of Japan 2019). This region, located between 20° and 30° north latitude, is characterized by a rare subtropical oceanic climate, influenced by warm Kuroshio Current and monsoons, which result in annual precipitation exceeding 2000 mm.

As a result, it is one of the few places in the world where rainforests exist in the subtropical zone (Government of Japan 2019). In the mountainous forests of the region, evergreen broadleaved forests have developed in the humid subtropical climate. The dominant tree species in the upper canopy include mainly oaks (e.g., Castanopsis sieboldii and Lithocarpus edulis), Ryukyu pines, Pinus luchuensis, and laurel trees (Lauraceae). The forest is also home to a diverse range of plant species, such as tree ferns (Cyathea species), Lasianthus species, some Ardisia species, strangler figs (Ficus species), and palm trees (Arecaceae). Additionally, cloud forests and mountain stream vegetation have developed in the high mountainous areas. These forests, including those in the mid and low mountainous areas with similar species, are referred to as subtropical rainforests and are crucial for the wildlife in the region (Government of Japan 2019).

The nomenclature of the islands and regional divisions in this review follows the conventions outlined by Toyama (2014), which are based on the natural sciences, including geography, geology, and biology. Specifically, the entire region along the Ryukyu Archipelago includes island groups such as the “Osumi Island Group,” “Tokara Island Group,” “Amami Island Group,” “Okinawa Island Group,” “Sakishima Island Group” which encompasses the “Miyako Islands” and “Yaeyama Islands,” as well as the “Senkaku Island Group” and “Daito Island Group” (Fig. 1).

Island formation and characteristics of terrestrial mammalian fauna

The Ryukyu Archipelago is located at the intersection of the Eurasian Plate and the Philippine Sea Plate (Fig. 1). Geological processes, such as the subduction of the Philippine Sea Plate beneath the Eurasian Plate in the Ryukyu Trench, led to the formation of these islands during the Late Miocene and subsequent periods (Machida et al. 2001; Kimura 2002; Hase 2010; Iryu and Matsuda 2010; Government of Japan 2019). Furthermore, as a continental island, the Ryukyu Archipelago has undergone historical cycles of intermittent separation from and connection to the Eurasian Continent through deformation and formation of land bridges, respectively, resulting in the development of a unique biota and ecosystems in the Ryukyu Archipelago (Kizaki and Oshiro 1980; Motokawa 2000, 2017; Oshiro 2002; Ota 2002, 2012; Otsuka 2002; Sato 2017; Watanabe et al. 2023).

Fig. 1.

Island groups and main islands of the Ryukyu Archipelago including the Senkaku Island Group and the Daito Island Group [based on Toyama (2014) and Japanese Government (2019) and modified from Izawa and Yamada (2023), using Google Earth]. The Ryukyu Archipelago is divided into three regions: North Ryukyus (from the Osumi Strait and Tokara Strait), Central Ryukyus (from Tokara Strait to the Kerama Gap), and South Ryukyus (from the Kerama Gap to the Yonaguni Strait). The depths of Tokara Strait and Kerama Gap are both over 1000 meters under sea with widths of 50 km each. Four islands, including sites designated as Natural World Heritage, are marked with an asterisk. The names of each island are as follows: Amami-Oshima, Amami-Oshima Island; Tokunoshima, Tokunoshima Island; Okinawa, Okinawa Island; Ishigaki, Ishigaki-jima Island; Iriomote, Iriomote Island; Miyako, Miyako-jima Island, Uotsuri, Uotsuri-jima Island; Minami Daito, Minami Daito-jima Island; and Kita Daito, Kita Daito-jima Island.

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The Ryukyu Archipelago is subdivided into “North Ryukyus” between the Osumi Strait and the Tokara Strait, “Central Ryukyus” from the Tokara Strait to the Kerama Gap, and “South Ryukyus” from the Kerama Gap to the Yonaguni Strait (Fig. 1). Each region has a distinct historical trajectory and forms unique terrestrial mammalian communities. The depths of the Tokara Strait and the Kerama Gap exceed 1000 m, and their widths are approximately 50 km, geologically dividing the Ryukyu Archipelago. Biogeographically, the former is known as the Watase Line, and the latter as the Hachisuka Line.

Due to differences in the timing of continental connections and separations, distinct terrestrial mammalian assemblages have developed, especially in the central and southern Ryukyu Archipelago compared to those in the North Ryukyus, which are more similar to those of Kyushu Island, as shown in Table 1 (although data on the North Ryukyus are not presented here). Notable characteristics of the current mammalian fauna in the region include five key aspects: high diversity, high endemism, close relationships with biogeographical distribution patterns of the Indomalayan ecozone, a scarcity of large-sized mammals, and absence of top predatory mammals in the food chain—except on Iriomote Island in the South Ryukyus, where the Iriomote cat inhabits (Table 1). The island's structure, which poses challenges for medium- to large-sized mammals to immigrate and establish themselves across islands, may contribute to their lower diversity compared to continental or larger islands in other regions. Nevertheless, the central and southern Ryukyu Archipelago, representing approximately 20% of the total terrestrial mammal species in Japan, demonstrates high diversity when considering the area ratio (0.7% of Japan). The endemic rate of species and subspecies, defined as the proportion of native species that exist only in a specific area, ranges from 67% to 77% of the native species in each island of the Central Ryukyus, and Ishigaki-jima and Iriomote-jima Islands of the South Ryukyus (Table 1). This high endemic rate is a major distinguishing feature of the region. When compared with the other four continental island areas in the subtropics (cf. 27% in Taiwan, 30% in Cuba, 30% in Jamaica, and 18% in the islands of the Gulf of California), the high level of endemism of the central and southern Ryukyu Archipelago is remarkable (Government of Japan 2019). The other three characteristics—high diversity, biogeographical distribution patterns of the Indomalayan ecozone, and absence of top predatory mammals—are closely linked to region's complex geological history and island nature.

The earliest history of human colonization and key historical events leading to the Modern era

The history of human habitation in the central and southern Ryukyu Archipelago dates back to approximately 30 000 years during the Paleolithic era (see the later section). Furthermore, significant human activities have shaped the islands, including the cultivation of sugarcane, Saccharum officinarum since the 17th century, intensified upland cultivation, forest utilization, and modern-era forestry practices for pulp production. Consequently, the original pristine natural environment has been replaced by secondary natural environments and forests with minimal primary habitats (Toyama 2016; Yoneda 2016, 2017). Despite intensified development during the Meiji period (1868–1912) and later, it is noteworthy that these regions did not experience widespread species extinctions, except for bats (see the later section).

In the following, Okinawa Island Group and Sakishima Island Group, and Amami Island Group are explained separately due to differences in history and administration in each area.

Okinawa Island Group and Sakishima Island Group

Human remains known as “Yamashita Cape People” were discovered in the Yamashita limestone cave in Naha City, Okinawa Island, and were estimated to be around 37 000–32 000 years old, making them the oldest human bones in Japan (Watanabe 1970; Takamiya et al. 1975). Contemporary bones have also been found in the southern part of Okinawa Island, with Sakitari Cave yielding evidence of settlements and the world's oldest fishhooks (Fujita et al. 2016). “The Minatogawa Man,” discovered between 1967 and 1969, is believed to date back approximately 18 000–16 000 years, exhibiting similarities to the Jomon people and Neolithic people of the continent (e.g., Suzuki and Hanihara 1982; Hokama 1986; Asato and Doi 1999; Tsujino et al. 2010). The recorded history then jumps to the shell mound period, approximately 6000 years ago, characterized by natural gathering activities. Settled villages were established approximately 3000 years ago (Asato and Doi 1999; Hayaishi 2011; Pearson 2013; Shinoda and Adachi 2017).

During this era, forests thrived on islands such as Miyako-jima Island, hosting diverse fauna, as suggested by fossils and archaeological sites, and human activities appeared to have significantly altered the natural environment, including the animal populations (Matsuoka 2000; Pearson 2013; Nakamura and Ota 2015; Watanabe et al. 2023).

Subsequently, after passing through the Gusuku period, the Ryukyu Kingdom was established in 1429. The kingdom unified the Amami Island Group and the Yaeyama Islands, expanding its dominion. Although the Amami Island Group later came under the control of the Satsuma Domain (now Kagoshima Prefecture) in 1609, the Ryukyu Kingdom persisted until its collapse in 1879 because of the Ryukyu Disposition by the Japanese government. It was then settled as Okinawa Prefecture.

During the pre-modern era, deforestation for construction and shipbuilding rapidly progressed in ancient Ryukyu, and reforestation efforts have been documented (Tawada 1972). As the early modern era unfolded in the 1600s, industrial development was pursued, leading to further rapid degradation of the forest environment. This continued until the mid-1700s, when the “Somayama” system (forest policy regulations regarding forest management and use) established by the kingdom was implemented, focusing on sustainable management (Nakama 2011).

Table 1.

Terrestrial mammals inhabiting the main islands of the central and southern Ryukyu Archipelago, their endemism to the region, and their conservation status

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However, as mentioned above, since Okinawa Prefecture was established in 1879, resurgence of deforestation activities has increased. Newspaper articles from that time expressed concern over the deforestation of forests in the northern part of Okinawa Island (called Yanbaru or Yambaru for the area's name) (Nakama 2011). Unfortunately, there is no record detailing how these changes affected the biodiversity in the area.

Okinawa Island became a battleground during the ground operations in World War II in 1945. Many lives and towns were lost, and forests in the central and southern parts disappeared. This wartime destruction significantly affected the current distribution of the flora and fauna. Post-war reconstruction efforts have led to the overuse of forests and their excessive development. Construction of logging roads, large-scale logging, and dams continued until the 1980s. Similar trends have been observed in the Miyako Islands, Yaeyama Islands, and other areas. The islands in Okinawa Prefecture, along with the Amami Island Group in Kagoshima Prefecture, were placed under U.S. military administration after the war, and the islands in Okinawa Prefecture were returned to Japanese administration in 1972 (see below about the Amami Island Group). During this period, “the 1953 Land Acquisition Act” resulted in the seizure of lands within the Okinawa Prefecture for military use. Nowadays, nearly 15% area of Okinawa Island is occupied by U.S. military bases (Okinawa Prefectural Office 2024).

Amami Island Group

In prehistoric times, evidence of human settlement in the Amami Island Group dates back over 30 000 years, as confirmed by the discovery of the “Aira Tanzawa Volcanic Ash” deposit layers from a volcanic eruption 30 000 years ago in the Kasari area of Amami City on Amami-Oshima Island and Isen Town on Tokunoshima Island. Below these layers, remnants of human activity suggest human habitation in the Amami Island Group 30 000 years ago (Hisashi et al. 2021). Artifacts from this period include bones of the Amami rabbit and the Ryukyu wild boar, suggesting that humans used these animals as food (Takamiya et al. 2016; Takamiya 2017, 2021; Toizumi 2018). The beginning of the “Jomon period,” i.e., the beginning of the shell mound period in Amami Island Group, is now estimated to be around 14 000 years ago, much earlier than previously thought (7000 years ago) (Hisashi et al. 2021; Takamiya 2021). During the equivalent of the “Yayoi period” on the Japanese mainland, when rice cultivation extended south to the Tokara Islands, the Amami Island Group relied on fishing and gathering, engaging in remote trade of large shellfish (e.g., Conus literatus, Strombus latissimus, and Turbo marmoratus) for ornamental purposes, extending to Kyushu and the Kansai region of the Japanese mainland, as well as overseas areas in East Asia.

In the early modern period, under the rule of the “Satsuma Domain” (current Kagoshima Prefecture) from 1609, the Amami Island Group underwent significant industry and human life changes through government policy (Hisashi et al. 2021). Large-scale cultivation of sugarcane plantations and the shift to black sugar production began in 1747. During this period, forests were extensively utilized for development of agricultural land, rice paddies, sugarcane fields, and for firewood.

After the end of the U.S. occupation of Japan (1945–1953) following World War II, the Amami Island Group was returned to Japan in 1953 and “Amami Islands Reconstruction Special Measures Law” was enacted in 1954 and is still ongoing to address regional disparities and promote various reconstruction and development projects, including continued basic infrastructure development, industrial growth, tourism, cultural promotion, and human resource development (Hisashi et al. 2021). During this period, land and forest development, flood control, and coastal development have intensified. Particularly, as a result of annual logging accumulation, more than 90% of the forests on Amami-Oshima Island had been logged in total, mainly for pulp chip material, during Japan's period of high economic growth (approximately between 1955 to 1985), significantly affecting local wildlife (Sugimura 2002). Today, many forests logged during this period have reached an age suitable for utilization, leading to the resumption of logging activities.

The earliest natural history records leading to the Modern era

The central and southern Ryukyu Archipelago has been recognized internationally—by countries such as China, the United States, and European nations—as a biologically valuable region since ancient times (7th century), particularly after a period of increased interactions, especially during the early modern period (18th century). This recognition is attributed to exchanges with China and visits by whaling ships, as described in detail later. Both international and domestic researchers from various research fields have visited the region for research purposes. Visiting scholars have preserved numerous valuable records, including the discovery of new species.

In the following, Okinawa Island Group and Sakishima Island Group, and Amami Island Group are explained separately as previous section.

Okinawa Island Group and Sakishima Island Group

Records of Okinawa Island's natural environment during the Ryukyu Kingdom era were described predominantly by foreign visitors. The earliest consolidated record of Ryukyus is found in the 7th century's “Zuisyo Ryukyukokuden” (Document of Ryukyu Kingdom on Geography, Flora and Fauna, and Other Subjects) published in China in 629 (Iki 2021). However, even when considering the fossil documentation found in later years, some of these records often differ from the present biological descriptions in Okinawa Island. The “Ryukyu Koku Yurai Ki” (Documents on Origin of the Ryukyu Kingdom) compiled by Ryukyu Kingdom in 1713, describes the origin of livestock and the introduction of the Kerama deer, Cervus nippon keramae (Kuroda, 1924), from the Satsuma Domain (current Kagoshima Prefecture) during 1628–1644. The document contains particularly valuable information, and also notes the native Ryukyu wild boar (Hokama and Hateruma 1997). The Japanese scholar Hakuseki Arai's “Nantoshi” (A History of the Southern Islands) (Arai 1719) and Xu Baoguang's “Chuzan Denshinroku” (Geography of Ryukyu) documented in China (Xu 1721) provided more specific records of flora and fauna, including the Yaeyama flying fox, Pteropus dasymallus yayeyamae Kuroda, 1933, dugongs, Dugong dugon (Müller, 1776), and Kerama deer. Occasional mentions of monkeys appear, supported by the discovery of bones of the Yakushima macaque, Macaca fuscata yakui (Kuroda, 1940), excaved in the Shurijo Castle of the Ryukyu Kingdom in Naha City on Okinawa Island. However, the Yakushima macaque is endemic to Yakushima Island in the North Ryukyus. Therefore, the Yakushima macaques were artificially brought from outside of Okinawa. Notably, the “Ryukyu Koku Shiryaku” (Documents of the Ryukyu Kingdom on Geography, History, and Other Subjects) published in China in 1756, mentioned the Kerama deer and a monkey whose species name was unidentified (Harada 2003). In the 1850s, Matthew C. Perry, an American naval officer who visited Okinawa Island in 1853–1854, and Charles Wright, a botanist, and William Stimpson, a zoologist, also visited in 1854–1855 by the North Pacific Exploring and Surveying Expedition recorded the flora and fauna of Okinawa Island (Perry 1856a, 1856b; Vasile et al. 2005; Goto 2017).

Shozaburo Watase (1862–1929), who was a professor of the University of Tokyo and the namesake of the Watase Line, a biogeographic line, made significant contributions to biogeography. However, he was also notable for his involvement in introducing the small Indian mongoose, Urva auropunctata (Hodgson, 1836), to Okinawa Island in 1910. Other noteworthy persons were Hyojiro Orii (1883–1970), a representative bird and mammal specimen collector who provided specimens to the British Museum, and to Yoshimaro Yamashina (1900–1989), an ornithologist, and Nagamichi Kuroda (1889–1978), an mammalogist (Motokawa and Maeda 2002). Orii's collected specimens, documented in the “Ryukyu and Osumi Islands Collection Journal (1921)” and “Ryukyu Collection Journal (1936)”, serve as valuable historical records for understanding the habitats of organisms during that time (Saito and Takehara 2013a, 2013b). Dedicating a species name to Hyojiro Orii, such as Orii's flying fox, P. d. inopinatus Kuroda, 1933, and Orii's shrew, Crocidura orii Kuroda, 1924, are also present.

When discussing Okinawa's biodiversity, a geological perspective is essential. The first geological survey of the Ryukyu Archipelago was conducted by the expedition of the American Squadron led by Matthew C. Perry in 1853 and by the North Pacific Exploring and Surveying Expedition led by John Rodgers in 1854 (see above). During the post-war American occupation, detailed geological maps were created by the U.S. Geological Survey (e.g., Flint et al. 1959). Records of animal fossils began with Hikoshichiro Matsumoto (1887–1975), covering the deer fossils, Cervus astylodon (Matsumoto, 1926), on Okinawa and surrounding islands (Hasegawa et al. 1973; Hasegawa 1980, 2012). Mitoshi Tokuda (1906–1975), initiated discussions of the geological history of the Okinawa Islands based on fossil analyses (Tokuda 1941). Subsequent discoveries, such as the fossils group at the Minatogawa River Fisher site on southern Okinawa Island and the Pinzaabu remains on Miyako-jima Island, have contributed to discussions on the origin of the fauna in the Ryukyu Archipelago (e.g., Hasegawa 2012; Hasegawa et al. 2018; Kawamura et al. 2016; Watanabe et al. 2023).

Amami Island Group

The first documented appearance of animals from Amami-Oshima Island was found in the folkloric book “Nanto Zatsuwa” (Ethnography of Amami-Oshima Island) (Nagoya ca. 1855), which details the flora, fauna, and customs of Amami-Oshima Island during the author's stay on the island from 1850 to 1855, in the late Edo period (1853–1868). This publication includes mentions of mammals such as the Amami rabbit, the Ryukyu long-furred rat, the Ryukyu wild boar, the musk shrew, Suncus murinus (Linnaeus, 1766), the Erabu flying fox, P. d. dasymallus Temminck, 1825, the dugong, and an unspecified species of rat. Livestock is also recorded. Among them, the Erabu flying fox is no longer found consistently on these islands now, though some records on a dead body, some individuals, and observation records were known both on Amami-Oshima and Tokunoshima Islands (Funakoshi 2017).

There was limited dissemination of information about the Amami Island Group to the Western world from the late Edo period to the early Meiji period (19th century). However, during the second expedition (1854–1855) by the North Pacific Exploring and Surveying Expedition (see above), the researchers visited Amami-Oshima, Kakeroma-jima, and Kikai-jima Islands. Plant specimens were collected, marking the first global dissemination of this information (Hamada 1993; Vasile et al. 2005; Goto 2017).

Articles by Ludwig Doederlein (1855–1936), a foreign lecturer and German zoologist at the University of Tokyo, detailing the geology, geography, flora, fauna, and customs of Amami-Oshima and the Kakeroma-jima Islands during his visit in 1880, was published in the mid-Meiji period (Doederlein 1881a, 1881b). Following this, visits by German horticulturists, plant merchants, researchers, and travelers also increased (Kreiner and Tabata 1992). Doederlein noted the presence of mammals such as wild boars, rabbits, rats, and bats but mentioned the absence of deer and carnivores on the islands. Furthermore, based on the distribution of plants, amphibians, and reptiles, he suggested that the boundary between the Old Northern and Oriental zoogeographic regions lies between Amami-Oshima Island and Kyushu Island (Doederlein 1881a, 1881b).

A review of subsequent and recent major research on terrestrial mammals

Here, we describe the main research topics related to each taxonomic group with a focus on endemic mammals in the central and southern Ryukyu Archipelago. By reviewing researches on these mammals, combined with the geographic history and human activities mentioned above, we highlight the characteristics of the region.

Overall, in the central and southern Ryukyu Archipelago, there are six orders, 11 families, and 26 species, including six subspecies, of native terrestrial mammals (Table 1). The number of endemic mammals is 20, including three relict endemic genera (Tokudaia, Diplothrix, and Pentalagus), resulting in a high endemic rate of 77% in the region. Sixteen of these species, i.e., 62% of native species, are listed as threatened species in the region, Critically Endangered (CR), Endangered (EN), and Vulnerable (VU), in the Red Lists of Japan (Ministry of the Environment 2020), and seven high-ranking species out of the 640 mammal species evaluated in the Evolutionarily Distinct and Globally Endangered (EDGE) Species List are recognized in the region. The EDGE is the first global conservation initiative to specifically focus on threatened species based on the IUCN Red List status that represent a significant amount of unique evolutionary history (Isaac et al. 2007; Gumbs 2023; EDGE Team 2024) (Table 1). The number of species on each island in the region is proportional to its area (Fig. 2). In particular, the Central Ryukyus, which were the first to become isolated from the continent for an extended period, have a higher number of species. Additionally, the percentage of non-chiropteran (bat) species out of the total number of species on the islands (excluding Uotsuri-jima Island due to the unknown habitat status of chiropteran species, see below) is also higher in the Central Ryukyus (Fig. 2). Furthermore, the characteristics of the mammalian fauna in the Central Ryukyus include evolutionarily distinct lineages of relict genera of rodent and lagomorph species, with an absence of top predatory mammals in the food chain, while the South Ryukyus are home to feline species found on a very small island (Table 1). Therefore, it can be said that the unique mammalian fauna in the central and southern Ryukyu Archipelago developed through different relationships with the continent over geological eras and the evolution of endemic species. Additionally, in this section, we describe research on six nonnative mammals (Table 2) and related human conflict issues.

Fig. 2.

Species-area relationships for native terrestrial mammals in the central and southern Ryukyu archipelago. Values in parentheses represent the area of the islands and the percentage of non-chiropteran species out of the total number of species on the islands (excluding Uotsuri-jima Island due to the unknown habitat status of chiropteran species). The names of each island are as follows: Amami-Oshima, Amami-Oshima Island; Tokunoshima, Tokunoshima Island; Okinawa, Okinawa Island; Ishigaki, Ishigaki-jima Island; Iriomote, Iriomote Island; Miyako, Miyako-jima Island, Uotsuri, Uotsuri-jima Island; Minami Daito, Minami Daito-jima Island; and Kita Daito, Kita Daito-jima Island. The area of Amami-Oshima does not include those of Kakeroma-jima, Uke-jima, Yoro-jima Islands, and other small islands around Amami-Oshima Island.

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Eulipotyphla

Four Eulipotyphla species are distributed in the Central Ryukyus, the South Ryukyus, and the Senkaku Island Group (Table 1). The number of endemic species among the four species is three, and the endemic rate is 75% in the region.

The Watase's shrew, Crocidura watasei Kuroda, 1924, is now considered a valid species based on karyotype differences, is endemic to the Central Ryukyus, and is thought to be a sister species to the Horsfield's shrew, C. horsfieldii (Tomes, 1856), which is common in South Asia (Motokawa et al. 1996; Hutterer 2005; Ohdachi et al. 2006; Motokawa 2015a). The species is listed as Near Threatened (NT) on the Red List of Japan (Ministry of the Environment 2020) (Table 1). The ecology of the Watase's shrew, such as reproduction, diet, habitat, and behavior, has been studied (e.g., Motokawa et al. 1996; Motokawa 2015a).

The Orii's shrew, C. orii Kuroda, 1924, is endemic to the Central Ryukyus and its closely related sister species has not yet been identified (Ohdachi et al. 2006; Motokawa 2015b). Although the Orii's shrew was previously thought to be a subspecies of the dsinezumi shrew, C. dsinezumi (Temminck, 1842), which is common in the Japanese mainland, morphological and genetic analyses have confirmed that it is an independent species (Motokawa 1998, 2003; Hutterer 2005; Motokawa 2015b). The species is listed as EN on the Red List of Japan (Ministry of the Environment 2020) (Table 1). There have been few studies on the life history of Orii's shrews partly because of their status as an endangered species.

The musk shrew, Suncus murinus (Linnaeus, 1766), on the islands in the Central and South Ryukyus was thought to be native, while populations in Kyushu were considered non-native, and its original range is estimated to have extended across Afghanistan, India, China, Taiwan, and continental and peninsula Indomalayan region (Hutterer 2005; Motokawa 2015c). A recent phylogenetic and population genetic analysis revealed that the population on the Ryukyus Islands expanded from Vietnam and southern China about 3300 years ago, likely in relation to human migration, with repeated immigration to the Ryukyu Islands in more recent years (Ohdachi et al. 2024).

The Senkaku mole, Mogera uchidai (Abe, Shiraishi & Arai, 1991), was first described by Hisashi Abe (Abe et al. 1991) as Nesoscaptor uchidai Abe, Shiraishi & Arai, 1991, based on a specimen of a young female collected in Uotsuri-jima Island in 1979 (Shiraishi and Arai 1980). However, Masaharu Motokawa reclassified it as Mogera uchidai (Abe, Shiraishi & Arai, 1991), recognizing that it is closely related to the insular mole, M. insularis (Swinhoe, 1863), from Taiwan, based on the morphological analysis and is thought to be distributed only on Uotsuri-jima Island (Motokawa et al. 2001; also see Yokohata 2015 for the species account). The species is listed as CR on the Red List of Japan (Ministry of the Environment 2020) (Table 1).

Challenges to obtain biological characteristics remain for species with limited available specimens, such as Orii's shrew (approximately ten specimens) (Abe 2005) and the Senkaku mole (only one specimen) (Abe et al. 1991; Motokawa et al. 2001; Yokohata 2015). However, due to the difficulty of accessing its habitat on Uotsuri-jima Island, information about its population size and the current status is still lacking, and further research is needed.

Chiroptera

A total of 13 species, including four subspecies, of Chiroptera are distributed in the Central Ryukyus, the South Ryukyus, and Daito Island Group (Table 1). The ten species and subspecies are endemic among these 13 species and subspecies, and the endemic rate is 77% in the region.

The Ryukyu flying fox, Pteropus dasymallus Temminck, 1825, has been confirmed on the islands in the North, Central, and South Ryukyus, as well as Senkaku and Daito Island Groups, and on islands in Taiwan and Philippines (Kinjo and Nakamoto 2015). In Japan, four subspecies have been classified (Yoshiyuki 1989; Maeda 1996; Simmons 2005; Kinjo and Nakamoto 2015); the Erabu flying fox, P. d. dasymallus, Kuroda, 1933, on the islands of the Osumi and the Tokara Island Groups of the North Ryukyus, the Orii's flying fox, P. d. inopinatus, Kuroda, 1933, on the Okinawa Island Group, the Yaeyama flying fox, P. d. yayeyamae Kuroda, 1933, on the islands of the South Ryukyus, and the Daito flying fox, P. d. daitoensis, Kuroda, 1921, on the islands of the Daito Island Group. In Taiwan, the Formosan flying fox, P. d. formosus Sclater, 1873, is classified (Sclater 1873). This species also occurs on the northern islands of the Philippines, but its taxonomic status is unclear. Recent molecular studies have revealed differences among the subspecies (Chen et al. 2021; Taki et al. 2021). The Daito flying fox is listed CR on the Red List of Japan (Ministry of the Environment 2020), as well as Endangered Species of Wild Fauna and Flora, and National Natural Monument (Table 1). Research on the distribution and ecology of the Ryukyu flying fox has primarily focused on the Orii's flying fox (e.g., Nakamoto et al. 2011, 2012, 2016). In recent years, research has been conducted on the Daito flying fox, an oceanic island subspecies, examining its relationship with the unique island environment and its conservation (Izawa et al. unpublished). Additionally, temporal changes in the geographic distribution of the Ryukyu flying fox across the islands of the Ryukyu Archipelago have been explored (Nakamoto 2017). The habitat status of the Ryukyu flying fox on Uotsuri-jima Island in the Senkaku Island Group, as observed in the 1953 survey; however, since then and up to the present, it remains unknown due to inaccessibility to the island, and further research is needed (Takara 1954; Nakamoto 2017).

The Okinawa flying fox, Pteropus loochoensis Gray, 1870, was recorded only from Okinawa Island; however, its taxonomic status remains uncertain, and it is considered to be extinct (Kinjo 2015). Three or four specimens collected from Okinawa Island in the 19th century, but there have been no further records of collection or observation since it was described, and the details are completely unknown (Gray 1870; Yoshiyuki 1989; Maeda 1996; Simmons 2005; Kinjo 2015; Nakamoto 2023). There are two possible explanations: it may have become extinct shortly after the type specimens were collected, or the location where the specimen was collected may have been recorded incorrectly.

The Okinawa little horseshoe bat, Rhinolophus pumilus Andersen, 1905, is endemic to the Okinawa Island Group and, formerly, to the Miyako-jima Island in the Sakishima Island Group (Sano and Armstrong 2015b). However, the subspecies of this bat, the Miyako little horseshoe bat, R. p. miyakonis Kuroda, 1924, which was found only on Miyako-jima Island, is now considered extinct, with no specimens collected since the last four specimens were lost in a fire (Yoshiyuki 1989; Maeda 1996; Kinjo 2015; Sano and Armstrong 2015b; Sano and Tamura 2023). The Yaeyama little horseshoe bat, R. perditus Andersen, 1918, is endemic to the islands in the Sakishima Island Group, and the Orii's little horseshoe bat, R. cornutus orii Kuroda, 1924, is an endemic subspecies of the Amami Island Group (Sano and Armstrong 2015b; Sano and Tamura 2023). The Orii's little horseshoe bat is a subspecies of the Japanese little horseshoe bat, R. cornutus Temminck, 1834, which is endemic to and widely distributed across Japan (Sano and Armstrong 2015a). The three Rhinolophus species, R. pumilus, R. perditus, and R. cornutus, have been considered synonyms of R. cornutus and there are low levels of sequence divergence among them in molecular analyses (Li et al. 2006; Sano and Armstrong 2015a). The Okinawa little horseshoe bat and the Yaeyama little horseshoe bat have been proposed as subspecies or separate species, with ongoing taxonomic discussions (Simmons 2005; Sano and Armstrong 2015a, 2015c). Challenges regarding habitat status and taxonomic positioning remain for species with limited available specimens, such as the extinct Okinawa flying fox. The Okinawa little horseshoe bat is listed as EN on the Red List of Japan (Ministry of the Environment 2020), and Endangered Species of Wild Fauna and Flora. The Yaeyama little horseshoe bat is designated as VU on the Red List of Japan (Ministry of the Environment 2020). The Orii's little horseshoe bat is EN on the Red List of Japan (Ministry of the Environment 2020), and Endangered Species of Wild Fauna and Flora (Table 1).

The lesser leaf-nosed bat, Hipposideros turpis Bangs, 1901, is endemic to islands of the Yaeyama Island Group and is a distinct species from those found in Thailand and Vietnam, as analyzed through morphological and genetic studies (Simmons 2005; Thong et al. 2012; Sano and Diaz 2015). Populations of the lesser leaf-nosed bat on Hateruma and Yonaguni Islands of the Yaeyama Island Group are listed as a Local Population (LP) on the Red List of Japan (Ministry of the Environment 2020), as well as Endangered Species of Wild Fauna and Flora, and are ranked 328th by EDGE Team (2024) (Table 1).

The Japanese pipistrelle, Pipistrellus abramus (Temminck, 1984), is widely distributed across East Asia, including southern Ussuri, China, Taiwan, Korea, Vietnam, Myanmar, India, and Japan, with populations in the Central and South Ryukyus (Simmons 2005; Kawai 2015a).

The Japanese large-footed bat, Myotis macrodactylus (Temminck, 1840), is widely distributed across East Asia, including eastern Siberia, southern Sakhalin, and Japan, with populations in the North Ryukyus and on Amami-Oshima and Tokunoshima Islands in the Central Ryukyus (Sano and Ishida 2015).

A new species of small bat, the Yanbaru Myotis, M. yanbarensis Maeda & Matsumura, 1998, was discovered in 1996 (Maeda and Matsumura 1998). The Yanbaru Myotis is endemic to Amami-Oshima and Tokunoshima Islands, and the northern part of Okinawa Island in the Central Ryukyus, and is closely related to the frosted Myotis, M. pruinosus Yoshiyuki, 1971, endemic to the Japanese mainland, and is also grouped with the Burmese whiskered Myotis, M. montivagus (Dobson, 1874), from Malaysia and the hairy-faced Myotis, M. annectans (Dobson, 1871), from Thailand (Maeda and Matsumura 1998; Kawai et al. 2003; Simmons 2005; Kawai 2015b, 2015c). The species is listed as EN on the Red List of Japan (Ministry of the Environment 2020), as well as Endangered Species of Wild Fauna and Flora, and is ranked 147th by EDGE Team (2024) (Table 1).

The East-Asian little bent-winged bat, Miniopterus fuscus Bonhote, 1902, is endemic to mainly Amami-Oshima, Tokunoshima, and Okinawa Islands in the Central Ryukyus, and Ishigaki and Iriomote Islands in the South Ryukyus (Simmons 2005; Sano 2015a). The species is listed as EN on the Red List of Japan (Ministry of the Environment 2020), and Endangered Species of Wild Fauna and Flora (Table 1).

A new species of small bat, the Ryukyu tube-nosed bat, Murina ryukyuana Maeda & Matsumura, 1998, was discovered in 1996 (Maeda and Matsumura 1998). The Ryukyu tube-nosed bat is endemic to Amami-Oshima and Tokunoshima Islands, and the northern part of Okinawa Island in the Central Ryukyus (Simmons 2005; Kawai 2015d). The species is listed as EN on the Red List of Japan (Ministry of the Environment 2020), as well as Endangered Species of Wild Fauna and Flora, and is ranked 346th by EDGE Team (2024) (Table 1). Studies have been conducted on the ecology of the species (e.g., Funakoshi et al. 2019; Preble et al. 2021a, 2021b). Ongoing research anticipates the further discovery of new species and their records as noted below.

The Oriental little free-tailed bat, Tadarida latouchei Thomas, 1920, is known from China, Laos, Thailand, and Japan, and in Japan a single specimen has been collected since 1969, from each of Kuchinoerabu-jima in the North Ryukyu, and Amami-Oshima and Yoron-jima Islands in the Central Ryukyus (Sano 2015b; Funakoshi 2023). The species is considered clearly distinct based on morphological characteristics from the European free-tailed bat, T. teniotis (Rafinesque, 1814), and the East Asian free-tailed bat, T. insignis Blyth, 1862, which is distributed across China, Korea, the Ussuri region, Taiwan, and Japan (Funakoshi and Kunisaki 2000; Simmons 2005). The species is listed as Data Deficient (DD) on the Red List of Japan (Ministry of the Environment 2020) (Table 1).

Because Chiroptera species are volant, they sometimes stray into areas during typhoons or when transported in cargo. In recent years, the Chinese pipistrelle, Hypsugo pulveratus (Peters, 1871), which is distributed across southeastern China, Taiwan, Thailand, Laos, and Vietnam, has been found on Amami-Oshima Island (Funakoshi et al. 2022), and the black-bearded tomb bat, Taphozous melanopogon Temminck, 1841, which is distributed in Southeast Asia, has been found on Okinawa Island (Kobayashi et al. 2022). However, it is unclear whether the populations of these species have become established in the central and southern Ryukyu Archipelago.

Rodentia

Six Rodentia species were distributed on the Central Ryukyus and Senkaku Island Group (Table 1). The number of endemic species among the six species is four, and the endemic rate is 67% in the region.

Many islands in this region remain insufficiently surveyed, and ongoing research has revealed new insights, such as the division of the genus Tokudaia into three species and other findings (e.g., Endo and Tsuchiya 2006; Terao et al. 2022; also see Iwasa 2015a, 2015b, 2015c; Jogahara 2016).

The Amami spiny rat, Tokudaia osimensis (Abe, 1933), was first described by Yoshio Abe (Abe 1933) based on specimens from Amami-Oshima Island and initially classified Rattus jerdoni osimensis Abe, 1933. However, Mitoshi Tokuda (Tokuda 1941) later demonstrated that this form was distinct from R. jerdoni found in India and that its cranial and dental characteristics were more similar to those of Apodemus than Rattus, and proposed a new genus, Acanthomys osimensis (Abe, 1933). Subsequently, Nagamichi Kuroda (Kuroda 1943) established the genus Tokudaia and classified Tokudaia osimensis (Abe, 1933) within it. In contrast, David H. Johnson (Johnson 1946), based on his new specimens collected from the northern part of Okinawa Island, classified this form under a different genus, Tokudamys osimensis osimensis (Abe, 1933), and proposed a new subspecies, Tokudamys osimensis muenninki Johnson, 1946. However, Ellerman and Morrison-Scott (1951) reorganized the classification using Kuroda's genus Tokudaia, recognizing the Amami spiny rat as the subspecies Tokudaia osimensis osimensis (Abe, 1933), while the Okinawa spiny rat was classified as Tokudaia osimensis muenninki (Johnson, 1946). Finally, Musser and Carleton (1993) reclassified the Amami spiny rat as Tokudaia osimensis (Abe, 1933), and the Okinawa spiny rat as T. muenninki (Johnson, 1946), recognizing each as a distinct species, and this classification has been maintained since then (Kawamura 1989; Kaneko and Murakami 1996; Kaneko 2001; Musser and Carleton 2005; Kaneko 2006). The Tokudaia species found on Tokunoshima Island was confirmed in 1977, and Hideki Endo and Kimiyuki Tsuchiya (Endo and Tsuchiya 2006) described it as a new species, named the Tokunoshima spiny rat, T. tokunoshimensis Endo & Tsuchiya, 2006. The relict genus Tokudaia is thought to have diverged from the allied genus Apodemus and other species of the Murinae lineage in the Late Miocene, Okinawa spiny rats diverged from the ancestral lineage ca. 2.5 Mya and Tokunoshima spiny rats and Amami spiny rats branched from the lineage ca.1 Mya (Sato and Suzuki 2004; Murata et al. 2012; Kinoshita et al. 2025). The Amami spiny rat, which is endemic to Amami-Oshima Island, is listed as EN on the Red List of Japan (Ministry of the Environment 2020), as well as Endangered Species of Wild Fauna and Flora, National Natural Monument, and is ranked 79th by EDGE Team (2024) (Table 1). The Okinawa spiny rat, which is endemic to the northern part of Okinawa Island, is listed as CR on the Red List of Japan (Ministry of the Environment 2020), as well as Endangered Species of Wild Fauna and Flora, National Natural Monument, and is ranked 29th by EDGE Team (2024) (Table 1). The Tokunoshima spiny rat, which is endemic to Tokunoshima Island, is listed as EN on the Red List of Japan (Ministry of the Environment 2020), as well as National Natural Monument, Endangered Species of Wild Fauna and Flora, and is ranked 75th by EDGE Team (2024) (Table 1). The variations in karyotypes and unique sex chromosomes have been reported across the three Tokudaia species, revealing a novel sex-determination mechanism that was first identified in mammals (e.g., Murata et al. 2012; Kuroiwa 2015; Terao et al. 2022). Morphological discrimination between the Amami spiny rat and the Okinawa spiny rat (Kaneko 2001), captive breeding experiments on Amami spiny rats (Shinohara et al. 2013; Ministry of the Environment 2017), rediscovery of survival and historical distribution, foods, and behavior of Okinawa spiny rats (Yamada et al. 2010; Kudaka and Kudaka 2017b; Yasuda et al. 2017; Kotaka et al. 2021) and the survey on the distribution of Tokunoshima spiny rats (Jogahara et al. 2020) have been carried out.

The striped field mouse, Apodemus agrarius (Pallas, 1771), was first recognized in 1970 and confirmed in 1979 by the capture of two individuals on Uotsuri-jima Island in the Senkaku Island Group (Shiraishi and Arai 1980). This species is widely distributed across Eurasia, from Western Europe to Lake Baikal, and from the Amur River in the east to China, Korea, Taiwan, and Uotsuri-jima Island in Japan (Iwasa 2015d). However, due to the difficulty of accessing its habitat, information about its population size and the current status is still lacking, and further research is needed (Shiraishi et al. 1977; Shiraishi and Arai 1980). The species is listed as CR on the Red List of Japan (Ministry of the Environment 2020) (Table 1).

The Ryukyu long-furred rat, Diplothrix legata (Thomas, 1906), is a monospecific genus and endemic to Amami-Oshima and Tokunoshima Islands, and the northern part of Okinawa Island (Iwasa 2015e; Jogahara 2016). The original description of the Ryukyu long-furred rat was provided by Oldfield Thomas (Thomas 1906) based on a specimen collected by Alan Owston from Amami-Oshima Island as Lenothrix legata Thomas, 1906, because of its similarity to the gray tree rat, L. cana Miller, 1903, found on Sumatra Island in Indonesia. However, Thomas (1916) revised the genus to Diplothrix legata (Thomas, 1906) after comparing it with specimens of Indian species collected in British Sikkim in India. The species name was later supported by researchers such as Kuroda (1940) and Tokuda (1941). Although Ellerman (1941) and Ellerman and Morrison-Scott (1951) proposed Rattus legatus (Thomas, 1906), subsequent examinations by researchers such as Misonne (1969), Musser and Boeadi (1980), and Kawamura (1989) identified it as Diplothrix legata (Thomas, 1906), a name that is currently used (Musser and Carleton 1993, 2005; Kaneko and Murakami 1996; Kaneko 2006). The relict genus Diplothrix is thought to have diverged from the Rattus group more recently than Tokudaia diverged from the Apodemus group, and its lineage was established by at least the beginning of the Pleistocene (Suzuki et al. 2000; Kinoshita et al. 2025). The species is listed as EN on the Red List of Japan (Ministry of the Environment 2020), as well as Endangered Species of Wild Fauna and Flora and National Natural Monument (Table 1). Surveys of fossils and archeological records from the Holocene and the 11th to 15th centuries, aimed at elucidating the historical distribution of the species in the Central Ryukyus, have been conducted (Nakamura 2018). Genetic diversity (Okano et al. 2015; Kinoshita et al. 2025), morphology (Okano and Onuma 2015; Iwasa et al. 2020; Kubo et al. 2025; Nakanishi et al. 2025), ecological characteristics and role in forest ecosystems (Nago et al. 2019; Kobayashi et al. 2022: Higashi and Kobayashi 2023, 2025; Yamato et al. 2024) have been investigated. Food habits in the northern part of Okinawa Island (Kudaka and Kudaka 2017a; Kobayashi et al. 2025; Kubo et al. 2025), and food habits and some mating behaviors on Amami-Oshima Island (Makino 2020) have been revealed. Distribution surveys have been conducted in the northern part of Okinawa Island (Taniguchi et al. 2019) and Tokunoshima Island (Jogahara and Koshimoto 2017).

The Ryukyu mouse, Mus caroli Bonhote, 1902, is found only on Okinawa Island in Japan, but it is widely distributed across Southeast Asia, including Taiwan, Hainan, southern China, Malaysia, Vietnam, and Sumatra Island in Indonesia (Iwasa 2015f). The population of this species on Okinawa Island is thought to have recently invaded and may be non-native, based on morphological and genetic analyses compared to populations from Taiwan and other regions, as well as fossil records, although M. musculus has been found in the Holocene in the South Ryukyus (Motokawa et al. 2003; Shimada et al. 2007; Kawamura et al. 2016; Nishioka et al. 2016).

Lagomorpha

One species of Lagomorpha, the Amami rabbit, Pentalagus furnessi (Stone, 1900), is distributed on the Amami-Oshima and Tokunoshima Islands in the Central Ryukyus (Table 1). The species is endemic, and the endemic rate is 100% in the region.

The original description of the Amami rabbit was made by Witmer Stone (Stone 1900) as Caprolagus furnessi Stone, 1900, based on specimens collected by William H. Furness and Hiram M. Hiller on Amami-Oshima Island in 1896. Later, Marcus W. Lyon (Lyon 1904) reorganized the classification of the family Leporidae, creating a new genus for the Amami rabbit as Pentalagus furnessi (Stone, 1900), because the specimen had only five upper cheek teeth and lacked a third upper molar. Since then, the species has been classified under a monotypic genus (Hoffmann and Smith 2005; Yamada and Cervantes 2005; Yamada 2015; Yamada 2017). Molecular phylogenetic analyses revealed that the relict genus Pentalagus and its allied genera were thought to have diverged from each other ca. 9.44 Mya and its timing is also likely to be consistent with the paleogeographic explanation that the Central Ryukyus had been a part of the Eurasian Continent during the Middle Miocene but became separated from the continent since the Late Miocene to early Pleistocene (Yamada et al. 2002; Matthee et al. 2004; Government of Japan 2019; Kinoshita et al. 2025). Fossils of the genus Pliopentalagus have been found in the Yangtze River Basin in Anhui Province in eastern China on the Eurasian Continent, dating from 6 Mya to 3 Mya (Tomida and Jin 2002), and Pliopentalagus okuyamai Tomida & Takahashi 2023, collected in Mie Prefecture in the Japanese mainland dating from 3 Mya to 2.5 Mya (Tomida and Takahashi 2023; Tomida et al. 2024), and fossils of the genus Pentalagus on Okinawa Island dating from 1.7 Mya to 1.3 Mya and 0.4 Mya (Ozawa 2009), and fossils of present species on Tokunoshima Island probably dating to 0.03–0.018 Mya (Tomida and Otsuka 1993) have been discovered. The species is listed as EN on the Red List of Japan (Ministry of the Environment 2020), as well as Endangered Species of Wild Fauna and Flora and National Natural Monument, and is ranked 69th by EDGE Team (2024) (Table 1).

The first research on the distribution, ecology, and population status of the Amami rabbit on Amami-Oshima Island was conducted to designate the National Natural Monument, a year after the enactment of the “Historical Sites and Natural Monuments Protection Act” in 1919 (Uchida 1920). Over 40 years later, from 1963 to 1992, observations of captive individuals and outdoor surveys were conducted by Yamato Village Elementary and Junior High School on Amami-Oshima Island (e.g., Kirino 1977; Hiragi et al. 2024). Observations of nests, fecal distribution, and parasite research were carried out by the Medical Institute on Amami-Oshima Island of the University of Tokyo (e.g., Suzuki 1985). Researches on rearing and reproduction in captivity was also carried out in a laboratory and a zoo (Matsuzaki et al. 1989; Sako et al. 1991).

Distribution changes and population fluctuations (Sugimura and Yamada 2004; Seki et al. 2023; Ministry of the Environment unpublished), home range (Yamada et al. 2000), food habits (Asari and Kimoto 2022; Suetsugu and Hashiwaki 2023; Kubo et al. 2025), genetic analyses (Yamada et al. 2002; Ohnishi et al. 2017; Ando et al. 2018; Kinoshita et al. 2025), and morphology and growth (Hayashida et al. 1967; Otsuka et al. 1980, 1981; Hayashi et al. 2025; Gunji et al. 2025) have also been investigated mainly on Amami-Oshima Island and also Tokunoshima Island. Research on reproduction based on sensor camera surveys has revealed the detailed maternal behavior from prebirth to near the period of independence for offspring on Amami-Oshima Island (Suzuki and Oumi 2017b; Hamada and Mizuta 2020).

Carnivora

One subspecies of Carnivora, the Iriomote cat, Prionailurus bengalensis iriomotensis (Imaizumi, 1967), is distributed only on Iriomote Island of the South Ryukyus (Table 1). The Iriomote cat is endemic subspecies to the island and the endemic rate is 100% in the region.

Discovered by the animal literature writer Yukio Togawa in 1965, it was officially described as a new species by Yoshinori Imaizumi in 1967 (Imaizumi 1967). Initially it was considered a felid with a single genus and independent species as Mayailurus iriomotensis Imaizumi, 1967, because it was judged to maintain ancient traits. However, its taxonomic status has changed with the development of molecular genetic techniques and the accompanying revision of the classification of the Felidae as a whole. It has been classified as a separate species, first as Felis iriomotensis (Imaizumi, 1967) and Prionailurus iriomotensis (Imaizumi, 1967) (e.g., Wurster-Hill et al. 1987; Leyhausen and Pfleiderer 1994, 1999; Wozencraft 1993, 2005), and then subsequent taxonomic revisions now classify it as Prionailurus bengalensis iriomotensis (Imaizumi, 1967), endemic to Iriomote Island, and a subspecies of the mainland leopard cat, P. bengalensis (Kerr, 1792) (e.g., Masuda et al. 1994; Suzuki et al. 1994; Masuda and Yoshida 1995; Johnson et al. 1999; O'Brien and Johnson 2007). Twelve subspecies of the mainland leopard cat have been recorded, and more recently, the mainland leopard cat has been split into two species: the mainland leopard cat (including the subspecies Iriomote cat) and the Sunda leopard cat, P. javanensis (Desmarest, 1816) (Kitchener et al. 2017). The mainland leopard cat is widely distributed across the southeast Eurasian Continent, including India, Myanmar, Thailand, Indochina, China, Korea, and Japan, while the Sunda leopard cat is found in the Sunda Islands of Southeast Asia, including Sumatra, Borneo, and others (Kitchener et al. 2017). A review of the subspecies has been proposed (Patel et al. 2017), but this is currently under discussion. Processes of changes in taxonomy and relationships with fossil species are summarized in Nakanishi (2023) and Takahashi et al. (2023).

Since its discovery in 1965, the Iriomote cat has attracted international attention for both academic and conservation purposes. The IUCN Red List of 2018 designates it as a critically endangered subspecies; it is a rare occurrence, as it typically operates at the species level and is rarely specified at the subspecies level. In the IUCN Red List of 2021, the mainland leopard cat including the Iriomote cat was listed as Least Concern (LC) because of their wide distributions and stable population trends. However, an assessment report stated that “for the islands Iriomote and Tsushima in Japan and for Taiwan, the population sizes of the mainland leopard cat are supposed to be very small” (Ross et al. 2015; Ghimirey et al. 2023). The Iriomote cat is listed as CR on the Red List of Japan (Ministry of the Environment 2020), as well as Endangered Species of Wild Fauna and Flora, National Natural Monument (Table 1).

Following the discovery in 1965, research on Iriomote cat was undertaken by Tetsuo Takara of the Faculty of Agriculture at the University of the Ryukyus (Imaizumi and Takara 1971). Further ecological studies and conservation efforts were led by Sadao Ikehara of the Faculty of Science and Engineering (later the Faculty of Science) at the University of the Ryukyus. Research primarily centered on the University of the Ryukyus and Kyushu University has focused on habitat utilization, social structure, distribution, diet, behavior, ecology, and morphology, revealing the Iriomote cat's adaptation to life on a small island, specifically Iriomote Island, and its unique ecological traits among the world's felids (e.g., Watanabe et al. 2003; Watanabe and Izawa 2005; Nakanishi and Izawa 2015, 2016; Izawa and Nakanishi 2018; Doi and Izawa 2023; Tobe et al. 2024).

Artiodactyla

One subspecies of Artiodactyla, the Ryukyu wild boar, Sus scrofa riukiuanus Kuroda, 1924, is distributed and endemic subspecies to the Central and South Ryukyus (Table 1). The endemic rate is thus 100% in the region.

The Ryukyu wild boar was first described as S. leucomystax riukiuanus, Kuroda, 1924. However, the species name was later changed to scrofa, along with other species, due to synonyms across North Africa, Eurasia, South Russia, China, and other regions (Ellerman and Morrison-Scott1951; Grubb 1993). The Ryukyu wild boar is thought to be different from the Japanese wild boar, S. s. leucomystax (Temminck, 1842), common in the Japanese mainland, and other East Asian wild boars, based on morphological and DNA analyses (e.g., Imaizumi 1973; Watanobe et al. 1999; Endo et al. 2002; Kodera 2015; Yamada et al. 2018). Although the subspecies is genetically close to wild boars in Eastern Asia, the origin of the current subspecies is thought to be natural dispersal prior to its introduction by prehistoric humans (Ishiguro et al. 2008; Yoshikawa et al. 2016). Population of the Ryukyu wild boar on Tokunoshima Island is listed as LC on the Red List of Japan (Ministry of the Environment 2020) (Table 1).

Food habits, population fluctuation, and resource utilization by humans have been studied on Amami-Oshima and Iriomote-jima Islands, and the northern part of Okinawa Island (e.g., Handa 2000; Ishigaki et al. 2007; Ebihara 2009; Shimada et al. 2024). However, concerns regarding genetic introgression from the domestic pig, S. s. domesticus are likely to arise on the islands of the region, and further research is required (Watanobe et al. 2002; Tsuboi et al. 2011; Murakami et al. 2014; Takahashi et al. 2019). Predation of eggs of sea turtles (e.g., Caretta caretta and Chelonia mydas) and agricultural damage by the species have been reported, and concerns are growing regarding the impact on the ecosystem due to the increasing numbers of Ryukyu wild boars on some islands of the region (Sasai et al. 2016; Okinawa Prefectural Office 2020; Kagoshima Prefectural Office 2022).

Non-native mammals

Several non-native mammals, including the black rat, Rattus rattus (Linnaeus, 1758), the dog, Canis familiaris Linnaeus, 1758, the domestic cat, Felis catus Linnaeus, 1758, the Japanese weasel, Mustela itatsi Temminck, 1844, the small Indian mongoose, Urva auropunctata (Hodgson, 1836) [it was first recognized as the small Asian mongoose, Herpestes javanicus (Geoffroy Saint-Hilaire, 1818), and later classified to H. auropunctatus (Hodgson, 1836), but all Asian mongooses were later assigned to the genus Urva (Veron et al. 2007; Patou et al. 2009; Veron and Jenning 2017)], and the goat, Capra hircus Linnaeus, 1758, have been confirmed on various islands in this region, as shown by the six species listed in Table 2 (Ministry of the Environment 2021). Although other nonnative mammals, e.g., the European rabbit, Oryctolagus cuniculus (Linnaeus, 1758), and the Japanese wild boar, are temporarily found on some islands, only the species confirmed to have been established are shown in Table 2.

In non-native mammals, intensive research has been conducted on mongoose invasion in the northern part of Okinawa Island and on Amami-Oshima Island (Yamada et al. 2009; 2015; Ikeda and Yamada 2011; Ogura and Yamada 2011). Reproduction and morphology of mangooses and their food in the northern part of Okinawa Island (Ogura et al. 1998; 2001; 2002), the effects of mongooses on native species and the improvements of the mongoose eradication program on Amami-Oshima Island (Yamada 2002; Watari et al. 2008; Fukasawa et al. 2013a; Watari 2019), and the restoration of Amami spiny rat, Ryukyu long-furred rat, Amami rabbit, and other species on Amami-Oshima Island (Fukasawa et al. 2013b; Watari et al. 2013; Ministry of the Environment unpublished) have been studied. On the other hand, Okinawa spiny rat and Ryukyu long-furred rat in the northern part of Okinawa Island have also been monitored by the mongoose control program (Ministry of the Environment unpublished). The history of the mongoose introduction by humans from Okinawa Island to Amami-Oshima Island, and from Okinawa Island to Kagoshima City in Kyushu, was revealed through genetic analysis (Sato et al. 2023).

Table 2.

A summary of non-native mammals inhabiting the main islands of the central and southern Ryukyu Archipelago, which have already established themselves and are of concern due to their potential major impact on ecosystems

ta_ms2024-0044_002.gif

Research on invasive Japanese weasels has also been carried out regarding their diet and impact on native species in Miyako-jima Island, Minami Daito-jima Island, and Zamami Island (Sekiguchi et al. 2002; Kawauchi et al. 2018; Kobayashi et al. 2022).

Research has been conducted on actual condition of feral goats and their impact on environment. Due to inaccessibility to the island, surveys, such as aerial photography, were conducted on Uotsuri-jima Island of the Senkaku Island Group (Yokohata and Yokota 2000; Yokohata 2003; Yokohata et al. 2003, 2009; Takiguchi 2015), and research has also been conducted on Amami-Oshima Island (Watari 2016).

Additionally, studies have been conducted on the predation effects of free-ranging dogs on Amami-Oshima Island (Nakano and Murai 1996; Watari et al. 2007), as well as evaluations of predation by free-ranging domestic cats and surveys involving residents in the northern part of Okinawa Island, and on Amami-Oshima and Tokunoshima Islands (e.g., Jogahara et al. 2003; Izawa 2015; Shionosaki et al. 2015; Shionosaki 2016; Mameno et al. 2017; Suzuki and Oumi 2017a; Maeda et al. 2019; Kazato et al. 2020; Kobayashi et al. 2020; Qi et al. 2022). The identification of hair from native species for food habit analysis and DNA analysis of non-native carnivores on the bodies of endangered species have been studied and carried out in the northern part of Okinawa Island (Asato and Izawa 2020; Ministry of Environment unpublished).

Infection with Toxoplasma gondii, its definitive host being felines, including domestic cats, has been confirmed in an Amami spiny rat, Amami rabbit, invasive mongooses on Amami-Oshima Island, and invasive black rats and free-ranging domestic cats on Tokunoshima Island (Kubo et al. 2013; Tokiwa et al. 2019; Ito et al. 2020; Shoshi et al. 2021; Okada et al. 2022). Furthermore, infection with T. gondii has also been confirmed in livestock, such as pigs and goats, as well as in wild animals including black rats, musk shrews, Ryukyu wild boars, mongooses, and free-ranging domestic cats on Okinawa Island and the Yaeyama Islands (Kyan et al. 2013, 2021).

Roadkill, rehabilitating animals, and agricultural damage prevention caused by native mammals

Roadkill of endangered species by vehicles also occurs in this region. Particularly on islands, roadkill frequently occurs on roads that pass through or close to the habitats of endangered species. Research is being conducted on the environmental conditions of these incidents to develop preventive measures to protect Amami rabbits, Amami spiny rats, and other animals on Amami-Oshima Island (Hiragi et al. 2017; Asari and Fujiki 2020; Asari et al. 2020; Suzuki 2023), Ryukyu long-furred rats and Okinawa spiny rats in the northern part of Okinawa Island (Tamanaha et al. 2017; Miyamoto et al. 2021; Tamanaha and Watari 2023; Maruta et al. 2024), and Iriomote cat on Iriomote Island (Izawa et al. 2009; Yamamoto and Uchino 2023).

Researches on rehabilitating injured or sick individuals of endangered species that are primarily affected by roadkill or predation, such as the Ryukyu long-furred rat, the Okinawa spiny rat, the Amami rabbit, the Iriomote cat, and others, have been conducted (e.g., Nakaya et al. 2017; Ministry of the Environment unpublished).

Research has been conducted on using fences as a measure to prevent intrusion into farmland to mitigate agricultural damage. This includes damage to tankan orange Citrus tankan orchards, an important industry in the area, caused by the Amami rabbit on Amami-Oshima Island (e.g., Nakamura et al. 2023). Additionally, black rats, a non-native species, also cause damage to tankan oranges on Amami-Oshima Island (Yabe 1998). Although sugarcane and other agricultural products have been damaged by animals such as Ryukyu wild boars, Amami rabbits, and black rats, there has been little research on effective prevention methods. The only measures being implemented on agricultural sites are the use of rodenticides against black rats and the installation of fences or traps to control Ryukyu wild boars.

Outline of the history of conservation before and after the 1970's

We describe the national systems, policies, and conservation management, as well as academic initiatives, before and after the emergence of modern conservation in the 1970's, and outline the future conservation issues and challenges in the central and southern Ryukyu Archipelago.

National Natural Monuments and conservation of endangered species

Seven mammal species, including subspecies, in the central and southern Ryukyu Archipelago have been designated as National Natural Monuments by the Agency for Cultural Affairs of the Japanese Government (Table 1). The Amami rabbit was the first to be designated as a Natural Monument in 1921 (and was later elevated to a Special Natural Monument in 1963), and the spiny rat (genus Tokudaia) and Ryukyu long-furred rat were designated as natural monuments in 1972. The Iriomote cat was designated in 1972 and elevated as a Special Natural Monument in 1977, the dugong was designated in 1972, and the Daito flying fox was added in 1973.

The establishment of the Environmental Agency in 1971 and the reorganization of the Ministry of the Environment in 2001 by the Government of Japan marked the beginning of environmental administration at the national level. Since then, efforts have been made to commence and intensify the conservation and management of wildlife in the central and southern Ryukyu Archipelago. The international community has also directed attention to the central and southern Ryukyu Archipelago, leading to requests for the protection of wildlife and island ecosystems from organizations such as the World Wildlife Fund (WWF, established in 1961, and WWF Japan in 1971) and the International Union for Conservation of Nature (IUCN, established in 1948). These requests were based on surveys, including those for the Iriomote cat and Amami rabbit. The Government of Japan ratified the Washington Convention in 1980 to enhance domestic legislation. Subsequently, international conferences, such as the Convention on Biological Diversity (Earth Summit, 1992) and the Conference of the Parties to the Convention on Biological Diversity (Nagoya Summit, 2010) took place. These events provided opportunities for international understanding and cooperation, such as measures against the invasive mongoose on Amami-Oshima Island and the northern part of Okinawa Island under the “Invasive Alien Species Act (IAS Act),” enacted in 2005, aiming to prevent the harmful effects of invasive alien species (IAS) on the environment, human safety, and the agriculture, forestry, and fisheries industries, based on the list of the 100 of World's Worst Invasive Alien Species (Lowe et al. 2000).

The Ministry of the Environment enacted the “Act on the Conservation of Endangered Species of Wild Fauna and Flora” in 1994. At the first designation of endangered species, the Iriomote cat was listed in 1994, followed by the Daito flying fox and the Amami rabbit in 2004; the Amami spiny rat, Tokunoshima spiny rat, Okinawa spiny rat, and Ryukyu long-furred rat in 2016; and five small bat species (Ryukyu tube-nosed bat and Yanbaru Myotis in 2019, and Okinawa little horseshoe bat, Orii's little horseshoe bat, and East-Asian little bent-winged bat in 2020). In total, 12 species are listed (Table 1). The “Act on the Conservation of Endangered Species of Wild Fauna and Flora” includes provisions for individual protection and habitat conservation, along with the formulation of protection and breeding project plans. The Red List is an important indicator of conservation. After the IUCN published its first Red Data Book in 1966, the Japanese Ministry of the Environment issued a Japanese version in 1991 (Table 1). Subsequently, each prefecture, Okinawa and Kagoshima, created its own Red Data Book for their respective region. The first edition of Okinawa Prefecture's list was published in 1996, followed by revisions in 2005 and 2013. Considerations for the creation of the fourth edition are currently underway. The list included 22 mammalian species, including those categorized as LC or DD, were represented. The Kagoshima Prefecture's Red Data Book was published in 2003 based on surveys conducted from 1999 to 2002. The 2015 revised edition includes 15 species in the Amami Island Group, with no significant changes. According to the Ministry of the Environment's Red List, the Miyako little horseshoe bat was declared extinct in the 2020 edition owing to a lack of confirmation over a specific period. Following the Okinawa flying fox, this marks the second mammalian species to be declared extinct in the Central and South Ryukyus as mentioned in the previous section.

National parks and forest ecosystem protected areas

There are currently four national parks in the central and southern Ryukyu Archipelago. The Iriomote-Ishigaki National Park, established in 2007 with the incorporation of Ishigaki Island, was renamed from Iriomote National Park (established in 1972) to Iriomote-Ishigaki National Park and further expanded in 2016. Yambaru National Park, designated in 2016 and expanded in 2018, includes parts of the U.S. Marine Corps Northern Training Area's returned land. Kerama Islands National Park was established in 2014. While the national park mainly covers marine areas, it also includes conservation areas, such as the breeding sea areas of the humpback whale, Megaptera novaeangliae (Borowski, 1781), which migrates to the region annually. The Amami Islands National Park was designated in 2017. The Wildlife Conservation Centers of the Ministry of the Environment were established within these national parks. The Iriomote Wildlife Conservation Center was established in 1995, the Yambaru Wildlife Conservation Center was established in 1999, the Amami Wildlife Conservation Center was established in 2000, and the Tokunoshima Administration Office was established in 2013.

Another administrative agency involved in conserving endangered species at the national level is the Forestry Agency of the Ministry of Agriculture, Forestry and Fisheries. The Okinawa Forest Management Office, within the management of national forests, has designated “the Forest Ecosystem Protected Areas” (Iriomote Island in 1991 and the northern part of Okinawa Island in 2017), and the Kagoshima Forest Management Office, designated “the Forest Ecosystem Protected Areas” in national forests on Amami-Oshima and Tokunoshima Islands in 2013, implemented regulations for the conservation of highly diverse ecosystems. The monitoring and conservation of endangered species have also been conducted.

Natural World Heritage

The Natural World Heritage registration for “Amami-Oshima Island, Tokunoshima Island, Northern part of Okinawa Island, and Iriomote Island” was confirmed by the UNESCO on July 26, 2021 (UNESCO 2021). This marked Japan's fifth Natural World Heritage Site, following Shirakami-Sanchi (1993), Yakushima (1993), Shiretoko (2005), and the Ogasawara Islands (2011). The journey to registration of the central and southern Ryukyu Archipelago began in 1990 when the Nature Conservation Society of Japan included in their request to the government that the “unique biodiversity and habitats of the southwestern islands” should be considered candidates for World Heritage (Nature Conservation Society of Japan 1990). In 2003, the Ministry of the Environment and the Forestry Agency officially included this region as a candidate site for discussion. Subsequent preparations were made, and in-depth discussions aimed at preparing the nomination document began in 2013. The nomination document, aligned with Criteria IX (ongoing ecological or biological processes crucial for the evolution and development of ecosystems and species) and Criteria X (areas essential for biodiversity conservation), was submitted to UNESCO in 2017. During this period, the Yambaru National Park (2016), Amami Islands National Park (2016), and the Yambaru Forest Ecosystem Protected Area (2017) were newly designated as mentioned in the previous section. However, the nomination received an evaluation of “deferred registration” from IUCN. According to the evaluation, it did not meet the Outstanding Universal Value for the Criterion IX, citing issues such as the discontinuity of the recommended area owing to its enclave nature and the absence of returned lands from the U.S. Marine Corps Northern Training Area in the northern part of Okinawa Island. After a year of consideration following the integration of parts of discontinuity areas, the criteria were narrowed down to the Criteria X, and the recommended area was revised. The second nomination document was submitted in 2019. The World Heritage Committee was postponed during the 2020 COVID-19 pandemic. After twisting and turning, the final registration was achieved in 2021 (Fig. 3).

The four islands listed as Natural World Heritage Sites in Japan are home to 21 species of terrestrial mammals, 394 species of birds, 36 species of terrestrial reptiles, and 21 species of amphibians (note that the number of species is subject to change due to taxonomic revisions, and the figures mentioned here are based on the time of nomination) (Government of Japan 2019). Regarding endemism rates of species, including subspecies, on the four islands, terrestrial mammals accounted for 82%, birds for 48%, terrestrial reptiles for 87%, and amphibians for 86%, indicating high values (Government of Japan 2019). Among these, 20 species are internationally recognized as EDGE species (Isaac et al. 2007; Government of Japan 2019; Gumbs et al. 2023).

Countermeasures against invasive non-native mammals

Except for Iriomote Island, where the Iriomote cat lives, especially the Central Ryukyus, which originally lacked native predatory mammals, has faced significant threats to native wildlife and ecosystems from non-native mammals, such as mongooses, weasels, free-ranging domestic cats, dogs, and goats.

The mongoose control project, officially implemented by the Ministry of the Environment under “the Invasive Alien Species Act” enforced in 2005, was conducted on Amami-Oshima Island for nearly 30 years. The project has reduced the number of captured mongooses and the locations where they were trapped significantly (Ishii 2003; Fukasawa et al. 2013a; Hashimoto et al. 2016; Ministry of the Environment 2024). This reduction was achieved through various methods, including setting 30 000 traps per year, monitored by 300 sensor cameras per year, using three to 13 detection dogs annually, partially using rodenticides, and the Amami Mongoose Busters (about 40 members each year). On September 3, 2024, the Ministry of the Environment (2024) declared the successful eradication of mongooses on the island after confirming, based on two eradication probability evaluation models, that no mongooses had been captured by the traps or cameras, nor detected by the dogs, for six consecutive years since 2018, following 31 years of capturing a total of 32 645 mongooses.

Fig. 3.

Natural World Heritage Sites (NWHS), Buffer Zones (Buffer), and Surrounding Management Areas in Amami-Oshima Island, Tokunoshima Island, Northern Part of Okinawa Island and Iriomote Island [modified from Japanese Government (2019), and Izawa and Yamada (2023)]. Note: The white areas in the Northern Part of Okinawa Island indicate the U.S. Northern Training Area and others. NWHS, area of Natural World Heritage Site; Buffer, area of Buffer Zone; Island, area of whole island; U.S., the U.S. Northern Training Area; Area, total area of the three villages. The area of Amami-Oshima Island includes Kakeroma-jima, Uke-jima, Yoro-jima Islands, and other small islands around Amami-Oshima Island.

fi_ms2024-0044_003.jpg

The recovery of native species, such as the Amami rabbit, Amami spiny rat, and Ryukyu long-furred rats, indicates substantial progress in achieving the initial conservation goals (Ministry of the Environment 2024). However, vigilance is required against the potential re-invasion into Amami-Oshima Island from Okinawa Island, where mongooses have been established since 1910 as mentioned previously. Mongoose control efforts in the northern part of Okinawa Island have also shown positive results through trapping, sensor cameras, and detecting dogs with mongoose busters similar to those on Amami-Oshima Island, and fences to prevent the invasion of mongooses. However, continued control efforts in the northern part of Okinawa Island, including the targeted area to the south, are necessary.

Introduction of the Japanese weasel from Japanese mainland in the 1960s and 1970s for rat control has resulted in their establishment on islands in the central and southern Ryukyu Archipelago (Masuda and Watanabe 2015; Yamada 2021). Some islands have initiated measures to control the Japanese weasel (Okinawa Prefectural Office 2020).

The issue of predation by free-ranging domestic cats on native species has become evident on most islands, including Amami-Oshima Island, Tokunoshima Island, and the northern part of Okinawa Island (see the previous section). Although measures to remove free-ranging domestic cats from endangered native species' habitats have been implemented, there is an increasing need for comprehensive efforts, including proper management and ownership of domestic cats, which act as source populations (Maeda et al. 2019; Ministry of the Environment 2018, 2023; Kazato et al. 2020). The free-ranging domestic cat issue has moved to a new phase in terms of invasive species management, highlighted by the “Invasive Alien Species' List to Prevent Ecological Damage” published by the Ministry of the Environment (2015), and as part of islands designated as Natural World Heritage Sites. Similarly, predation problems caused by free-ranging dogs have also emerged, demanding comprehensive solutions.

Additionally, there is a feral goat problem in the central and southern Ryukyu Archipelago. While goats have traditionally been a source of food for people in the region, their feralization has led to vegetation damage, erosion along coastal cliffs, intrusion into forests, and negative impact on endangered species and ecosystems (Yokohata et al. 2003, 2009; Watari 2016). Control measures for feral goats in the northern part of Okinawa Island and on Iriomote Island have been initiated (Okinawa Prefectural Office 2023).

Overall, effective control of non-native species and comprehensive management strategies are crucial for conserving native species and ecosystems in the central and southern Ryukyu Archipelago.

Contribution of the academic communities to conservation

Various domestic and international academic communities and organizations have expressed interest in conserving this region. Among them, the Mammal Society of Japan has made particularly significant contributions.

The Mammal Society of Japan regularly submits requests and opinions to the Ministry of the Environment, the Okinawa and Kagoshima Prefectural Offices, and other relevant authorities regarding conservation measures for endangered mammals and the management of non-native species. These submissions aim to support and collaborate with the administrative policies and local community initiatives to provide reliable expert opinions. The Mammal Society of Japan plays a crucial role in guiding conservation efforts in the natural environment of the central and southern Ryukyu Archipelago. A total of 16 key requests and opinions regarding conservation in the central and southern Ryukyu Archipelago were submitted by the Mammal Society of Japan. This number constitutes a significant portion (23%) of the total requests and opinions (71 items) submitted by the Mammal Society of Japan from 1993 to 2022, highlighting the region's conservation challenges and the important role that the academic community has played in guiding conservation efforts in this region.

Principal issues and challenges of conservation

A common understanding is that the entire Ryukyu Archipelago, consisting of over 900 islands stretching from southern Kyushu Island to Taiwan, constitutes a valuable island group in terms of island biodiversity, and its value is not confined to any single island (e.g., Ota 2002, 2012; Kinoshita et al. 2025). Regrettably, only four representative islands were selected from a regulatory perspective in the context of Natural World Heritage registration. Furthermore, conservation issues related to Natural World Heritage Sites include that protected areas are limited land areas, fragmented conditions, scarcity of public land, the existence of the U.S. Marine Crop training area, and human activities, such as population of Amami-Oshima, Tokunoshima, the northern part of Okinawa, and Iriomote Island, counted 61 256, 23 497, 10 039 and 2402, respectively, in 2016 (Government of Japan 2019) (Fig. 3). In addition, the IUCN requests more information and measures on 1) tourist management plan for mitigation of overuse, 2) reduction of road fatalities of endangered species [including but not limited to Amami rabbits, Iriomote cats, and Okinawa rails, Hypotaenidia okinawae (Yamashina and Mano, 1981)], 3) river restoration options and dam removals to secure and enhance the integrity of aquatic ecosystems, 4) potential threats and mitigations to registered property from logging/timber extraction activities in buffer zones, and 5) monitoring implementation and information utilization based on comprehensive management plans and monitoring plans, which include the maintenance status of endangered species, reduction and improvement in human-induced impacts, decrease in invasive species, sustainable use in tourism, and understanding of the impact of climate change and disasters (UNESCO 2021).

However, the designation of the Ryukyu Archipelago as a Natural World Heritage Site marked a significant historical turning point and milestone, offering a valuable opportunity to share the region's geological, natural, and human history. By sharing these aspects among island groups, various fascinating features of the Ryukyu Archipelago are expected to unfold in the future. Historically, opportunities for mutual exchange and information sharing have been limited due to differences in administrative regions and among universities, research institutions, and organizations. However, the scope of sharing is expanding through the World Heritage Site platform, and efforts to address various issues are expected to progress.

Conclusion

The Ryukyu Archipelago, renowned for its globally significant natural environment and endemic species, has garnered attention as a biodiversity hotspot. The distinctive characteristic of the natural environment in this region is succinctly described as “diversity” and “endemism” which have become crucial keywords. Furthermore, the most notable feature of this region is that phylogenetically ancient mammal species have survived, and humans have been colonized here for the past approximately 30 000 years, coexisting with these species to this day and ensuring their continued existence. Such a region does not exist in other parts of Japan, and it is a globally rare phenomenon (Takamiya et al. 2016; Sato 2017; Takamiya 2017, 2021; van der Geer et al. 2021).

Although the unique characteristics of the islands contribute to their scientific value, research efforts have been directed mainly toward a few key species and islands. Consequently, comprehensive research on certain islands and species is lacking. There is concern that research efforts may disproportionately focus on registered Natural World Heritage Sites. Although the Natural World Heritage designation in 2021 is limited to the four islands under the World Heritage system, it is the consensus of the entire research community that the Ryukyu Archipelago, as an entire island group from southern Kyushu to Taiwan, has academic value (Government of Japan 2019). It is imperative to re-evaluate the entire Ryukyu Archipelago to advance research on biogeographical challenges, the characteristics of individual islands, biological communities, and the ecology of endemic species.

Biological research on the Ryukyu Archipelago has not only contributed to elucidating the taxonomy, ecology, and morphology of individual species, but has also contributed to establishing an ideal foundation for island biology research. Each island in the Ryukyu Archipelago, including many islands, has a different geological history and environment, which are mutually related to each other in the past and present (e.g., Ota 2002, 2012; van der Geer et al. 2021; Kinoshita et al. 2025). This can be considered a field of natural experiment. Understanding this region requires integration with geological fields. Since the first edition of “The Theory of Island Biogeography” was published in 1967 by MacArthur and Wilson (MacArthur and Wilson 2001), many studies have focused on “island” (e.g., Ota 2002, 2012; Gunji et al. 2025; Hayashi and Kubo 2025; Hayashi et al. 2025; Kinoshita et al. 2025; Kubo et al. 2025). Now, the development of new theories in the field of island biology, focusing on the evolution and adaptation of individual species with “islands” as a key concept, has begun on the Ryukyu Archipelago. These include topics such as ecosystem evolution, interspecific relationships, and changes and adaptations in response to climate change. The Japanese Archipelago is a collection of small islands from a global perspective and is considered a treasure house of biodiversity (Motokawa 2017; Sato 2017). We believe that various island theories can be disseminated worldwide from the study of the Ryukyu Archipelago, which is a typical island in terms of island biodiversity.

Simultaneously, this region hosts numerous endangered species, i.e., 62% of mammal species are classified as endangered (CR, EN, and VU) on the Japan's and IUCN's Red Lists (see Table 1). The conservation of the ecosystems of each island and each endangered species also requires an island perspective. In the field of island biology, it has been suggested that a small population size and small habitat area can lead to extinction. Specific factors related to conservation may also reflect the island's uniqueness. For example, the introduction of native species from one island to another can also threaten the uniqueness of the island, because the genetic structure of even the same species can sometimes differ from island to island. Furthermore, invasion of non-native species becomes an even greater threat to the uniqueness because the island's ecosystem is simple and vulnerable. In addition, the islands of the Ryukyu Archipelago have a long history of human settlement, and each island has a different human environment (history, industry, culture, customs, and other factors); therefore, it is necessary to consider conservation measures for each island. Information from ethnography, sociology, economics, and other fields is also required. It is our responsibility to conserve highly endangered wildlife species and to preserve the biodiversity of this region for future generations.

This collective effort aims to reveal novel insights into the interconnectedness among and unique evolutionary adaptations on the islands. The achievements of research and conservation efforts in the Ryukyu Archipelago will contribute to our understanding of island mammals and island biology. We hope that this review and special articles featured in this issue will be helpful for future studies and conservation efforts.

Acknowledgments:

We would like to thank Drs. Mugino O. Kubo, Shoji Hayashi, and Shun Kobayashi for their planning and management of this special issue. We would like to express our gratitude to the anonymous reviewers who provided useful comments and thorough reviews of the manuscript, covering a wide range of themes. We sincerely appreciate Drs. Tatsuo Oshida and Shingo Miura for their help, and Mr. Daisuke Nagaosa, Ms. Kumi Maruyama, Drs. Sota Niiyama, and Akira Sano for providing their information. We would also like to extend our thanks to Dr. Naomi Doi for her advice on the part related to the human history of the Ryukyu Islands, which is outside our area of expertise. We also thank Editage ( www.editage.jp) for English language editing. We would like to express our sincere gratitude to them. This study was financially supported by JSPS KAKENHI (grant no. 23K05910).

© The Mammal Society of Japan

References

1.

Abe, H. 2005. Order Insectivore. In( Abe, H., ed.) A Guide to the Mammals of Japan, Revised edition, pp. 4–24. Tokai University Press, Hadano (in Japanese). Google Scholar

2.

Abe, H., Shiraishi, S. and Arai, S. 1991. A new mole from Uotsuri-jima, the Ryukyu Islands. Journal of the Mammalogical Society of Japan 15: 47–60. Google Scholar

3.

Abe, Y. 1933. On the Amami Oshima spiny rat. Botany and Zoology 1: 936–942 (in Japanese). Google Scholar

4.

Andersen, K. 1905. On some bats of the genus Rhinolophus, with remarks on their mutual affinities, and descriptions of twenty-six new forms. Proceedings of the General Meetings for Scientific Business of the Zoological Society of London 2: 75–145. Google Scholar

5.

Andersen, K. 1918. Diagnosis of new bats of the Families Rhinolophidae and Megadermatidae. Annals and Magazine of Natural History 2: 374–384. Google Scholar

6.

Ando, H., Tsuda, Y., Kaneko, S. and Kubo, T. 2018. Historical and recent impacts on genetic structure of an island rabbit. Journal of Wildlife Management 82: 1658–1667. Google Scholar

7.

Arai, H. 1719. Nantoshi (A History of the Southern Islands). ( Arai, H. and Harada, N. 2015. Ezoshi and Nantoshi (A History of Ezo and A History of the Southern Islands. Heibonsha, Tokyo, 445 pp.) (in Japanese). Google Scholar

8.

Asari, Y. and Fujiki, S. 2020. Report on a preliminary test of roadkill observation system in Amami-Oshima Island, Japan. Wildlife and Human Society 8: 43–45 (in Japanese with English abstract). Google Scholar

9.

Asari, Y. and Kimoto, Y. 2022. Pentalagus furnessi food plants at two sites on the western Amami-Oshima Island, Japan. Wildlife and Human Society 10: 17–19 (in Japanese with English abstract). Google Scholar

10.

Asari, Y., Yamaguchi, R. and Hayakawa, Y. 2020. Decreasing road kill of Pentalagus furnessi with a wildlife detection system that warns drivers to reduce vehicle speed. Journal of JSCE 8: 1–4. Google Scholar

11.

Asato, H. and Izawa, M. 2020. Identification of species in Siricidae and Muridae on Okinawa-jima Island based on their hair morphology. Mammalian Science 60: 191–210 (in Japanese with English abstract). Google Scholar

12.

Asato, S. and Doi, N. 1999. Where Do Okinawans Come from – Origin and Formation of Ryukyu, Okinawans. Borderink, Naha, 198 pp. (in Japanese). Google Scholar

13.

Bangs, O. 1901. Notes on a small collection of mammals from the Liukiu Islands. American Naturalist 35: 561–562. Google Scholar

14.

Blyth, E. 1862. Report of curator, Zoological Department, May and June. Journal of the Asiatic Society of Bengal 30: 90–98. Google Scholar

15.

Bonhote, J. L. 1902. On some mammals obtained by the Hon N. Charles Rothschild from Okinawa, Liu-kiu Island. Novitates Zoologicae 9: 626–628. Google Scholar

16.

Borowski, G. H. 1781. Gemeinnüzzige Naturgeschichte des Thierreichs: darinn die merkwürdigsten und nüzlichsten Thiere in systematischer Ordnung beschrieben und alle Geschlechter in Abbildungen nach der Natur vorgestellet warden, Volume 2. bei Gottlieb August Lange, Berline, 196 pp. (in German). Google Scholar

17.

Büchner, E. 1890. Wissenschaftliche Resultate der von N. M. Przewalski nach central-Asien unternommenen Reisen auf Kosten einer von seiner Kaiserlichen Hoheit dem Grossfürsten Thronfolger Nikolai Alexandrowitsh gespendeten Summe herausgegeben von der Kaiserlichen. Zoologischer, Theil Band I. Säugethiere, V. Akademie der Wissenschaften St. Petersburg, St. Petersburg, 232 pp. (in German). Google Scholar

18.

Chen, S.-F., Juan, C.-H., Rossiter, S. J., Kinjo, T., Fukui, D., Kawai, K., Tsang, S. M., Veluz, M. J., Sakurai, H., Lin, H.-C. et al. 2021. Population genetic structure of the insular Ryukyu flying fox Pteropus dasymallus. Biotropica 53: 548–559. Google Scholar

19.

Desmarest, A. G. 1816. Le Chat de Java, Felis javanensis Nob. In( Société de naturalistes et d'agriculteurs, ed.,) Nouveau dictionnaire d'histoire naturelle, appliquée aux arts, à l'agriculture, à l'économie rurale et domestique, à la médecine. Tome 6, pp. 115. Chez Deterville, Paris (in French). Google Scholar

20.

Dobson, G. E. 1871. Notes on nine new species of Indian and Indo-Chinese Vespertilionidae, with remarks on the synonymy and classification of some other species of the same family. Proceedings of the Asiatic Society of Bengal 1871: 210–215. Google Scholar

21.

Dobson, G. E. 1874. Description of new species of Chiroptera from India and Yunan. Journal of the Asiatic Society of Bengal 43: 237–238. Google Scholar

22.

Doederlein, L. H. P. 1881a. Die Liu-Kiu-Insel Amami-Oshima. Mittheilungen der Deutschen Gesellschaft für Natur-und Völkerkunde Ostasiens (MOAG) 3: 103–117 (in German). Google Scholar

23.

Doederlein, L. H. P. 1881b. Die Liu-Kiu-Insel Amami-Oshima. Mittheilungen der Deutschen Gesellschaft für Natur-und Völkerkunde Ostasiens (MOAG) 3: 140–156 (in German). Google Scholar

24.

Doi, T. and Izawa, M. (ed.) 2023. The Iriomote Cat. University of Tokyo Press, Tokyo, 384 pp. (in Japanese). Google Scholar

25.

Ebihara, I. 2009. Study of the hunting practices and knowledge of a trap-hunter in Iriomote Island, Okinawa: based on trapping field maps over a period of 11 years. Bulletin of the National Museum of Ethnology 34: 131–165 (in Japanese with English abstract). Google Scholar

26.

EDGE Team. 2024. The 2024 EDGE Lists. Available at https://www.edgeofexistence.org/download-edge-lists/(Accessed 30 November 2024). Google Scholar

27.

Ellerman, J. R. 1941. The Families and Genera of Living Rodents Vol. 2. Family Muridae. British Museum (Natural History), London, 690 pp. Google Scholar

28.

Ellerman, J. R. and Morrison-Scott, T. C. S. 1951. Checklist of Palaearctic and Indian Mammals 1758 to 1946. British Museum (Natural History), London, 810 pp. Google Scholar

29.

Endo, H., Hayashi, Y., Yamazaki, K., Motokawa, M., Pei, J. C. K., Lin, L. K., Chou, C. H. and Oshida, T. 2002. Geographical variation of mandible size and shape in the wild pig (Sus scrofa) from Taiwan and Japan. Zoological Studies 41: 452–460. Google Scholar

30.

Endo, H. and Tsuchiya, K. 2006. A new species of Ryukyu spiny rat, Tokudaia (Muridae: Rodentia), from Tokunoshima Island, Kagoshima Prefecture, Japan. Mammal Study 31: 47–57. Google Scholar

31.

Feldhamer, G. A., Merritt, J. F., Krajewski, C., Rachlow, J. L. and Stewart, K. M. 2020. Mammalogy: Adaptation, Diversity, Ecology, Fifth edition. Johns Hopkins University Press, Baltimore, 725 pp. Google Scholar

32.

Flint, D. E., Saplis, R. A. and Corwin, G. 1959. Military Geology of Okinawa-Jima, Ryūkyū-rettō, Volume 5: Geology. Chief of Engineers, U.S. Army, Washington, 86 pp. Google Scholar

33.

Fujita, M., Yamasaki, S., Katagiri, C. and Kaifu Y. 2016. Advanced maritime adaptation in the western Pacific coastal region extends back to 35,000–30,000 years before present. Proceedings of the National Academy of Sciences of the United States of America (PNAS) 113: 11184–11189. Google Scholar

34.

Fukasawa, K., Hashimoto, T., Tatara, M. and Abe, S. 2013a. Reconstruction and prediction of invasive mongoose population dynamics from history of introduction and management: a Bayesian state-space modeling approach. Journal of Applied Ecology 50: 469–478. Google Scholar

35.

Fukasawa, K., Miyashita, T., Hashimoto, T., Tatara, M. and Abe, S. 2013b. Differential population responses of native and alien rodents to an invasive predator, habitat alteration and plant masting. Proceedings of the Royal Society B: Biological Sciences 280: 20132075. https://doi.org/10.1098/rspb.2013.2075Google Scholar

36.

Funakoshi, K. 2017. Report on a Ryukyu flying fox Pteropus dasymallus found on Tokunoshima Island. Nature of Kagoshima 43: 9–12 (in Japanese). Google Scholar

37.

Funakoshi, K. 2023. La Touche's free-tailed bat, Tadarida latouchei Thomas, 1920. In( Sano, A. and Fukui, D. eds.) Guide to the Bats of Japan, pp. 63–65. Bun-ichi Sougou Shuppan, Tokyo (in Japanese with English abstract). Google Scholar

38.

Funakoshi, K., Cheng, H.-C., Tamura, H. and Hsu, C.-W. 2022. A new record of Hypsugo pulveratus on Amami-Oshima Island, Japan and comparison with H. alaschanicus. Mammal Study 47: 225–233. Google Scholar

39.

Funakoshi, K. and Kunisaki, T. 2000. On the validity of Tadarida latouchei, with reference to morphological divergence among T. insignis and T. teniotis (Chiroptera, Molossidae). Mammal Study 25: 115–123. Google Scholar

40.

Funakoshi, K., Yamashita, K., Kitanokuchi, T., Tanaka, H., Otubo, S., Ohira, R., Uchihara, A., Osawa, T., Watanabe, K., Nagayama, T., et al. 2019. Ecological studies on the bat species of Tokunoshima Island and Amami-Oshima Island, Japan, with special reference to Ryukyu tube-nosed bat, Murina ryukyuana. Mammalian Science 59: 13–36 (in Japanese with English abstract). Google Scholar

41.

Geoffroy Saint-Hilaire, É. 1818. De l'Ichneumon. Ichneumon pharaon. In( Jomard, E. F., ed.). Description de l'Égypte, ou, Recueil des Observations et des Recherches qui ont été Faites en Égypte Pendant l' Éxpédition de l'Armée Française. Vol. Tome II, pp. 137–144. l'Imprimerie Royale, Paris (in French). Google Scholar

42.

Ghimirey, Y., Petersen, W., Jahed, N., Akash, M., Lynam, A. J., Kun, S., Din, J., Nawaz, M. A., Singh, P., Dhendup, T., et al. 2023. Prionailurus bengalensis (amended version of 2022 assessment). The IUCN Red List of Threatened Species 2023: e. T223138747A226150742s. Available at  https://www.iucnredlist.org/fr/species/223138747/226150742 (Accessed 30 November 2024). Google Scholar

43.

Goto, A. 2017. The Forgotten Black Ship, America's North Pacific Strategy and the Opening of Japan. Kodansya, Tokyo, 299 pp. (in Japanese). Google Scholar

44.

Government of Japan. 2019. Nomination of Amami-Oshima Island, Tokunoshima Island, Northern part of Okinawa Island and Iriomote Island for inscription on the World Heritage List. Government of Japan, Tokyo, 338 pp. Google Scholar

45.

Gray, J. E. 1870. Catalogue of Monkeys, Lemurs and Fruit-eating Bats in the Collection of the British Museum. British Museum (Natural History), London, 137 pp. Google Scholar

46.

Grubb, P. 1993. Order Artiodactyla. In( Wilson, D. E. and Reeder, D. M., eds.) Mammal Species of the World: A Taxonomic and Geographic Reference, Second edition, pp. 377–414. Smithsonian Institution Press, Washington and London. Google Scholar

47.

Gumbs, R., Gray, C. L., Böhm, M., Burfield, I. J., Couchman, O. R., Faith, D. P., Forest, F., Hoffmann, M., Isaac, N. B., Jetz, W., et al. 2023. The EDGE2 protocol: advancing the prioritisation of Evolutionarily Distinct and Globally Endangered species for practical conservation action. PLOS Biol 21: e3001991. https://doi.org/10.1371/journal.pbio.3001991Google Scholar

48.

Gunji, M., Taewcharoen, N., Yamada, F. and Sherratt, E. 2025. Does fast running limit numerical variability of the vertebral column in rabbits and hares (Leporidae: Lagomorpha)? Royal Society Open Science 12: 241813. https://doi.org/10.1098/rsos.241813Google Scholar

49.

Hamada, F. 1993. History of Amami Islands. Private Publication, Naze (Kagoshima), 209 pp. (in Japanese). Google Scholar

50.

Hamada, F. and Mizuta, T. 2020. Unique reproductive traits of the Amami rabbit Pentalagus furnessi: an endangered endemic species from southwestern Japan. Mammal Research 65: 805–813. Google Scholar

51.

Handa, Y. 2000. Questionnaires and hunting statistics for the habitation of Ryukyu wild boars in Amami Islands. Journal of the Japan Veterinary Medical Association 53: 525–528 (in Japanese). Google Scholar

52.

Harada, N. 2003. Ryukyu Koku Shiryaku (Documents of the Ryukyu Kingdom on Geography, History, and Other Subjects), complete Japanese annotated edition. Youjusyorin, Ginowan, 750 pp. (in Japanese). Google Scholar

53.

Hase, Y. 2010. Cenozoic tectonics. In(Geological Society of Japan, ed.) Regional Geology of Japan, Kyushu and Okinawa Region, pp. 15–20. Asakura Publishing, Tokyo (in Japanese). Google Scholar

54.

Hasegawa, Y. 1980. Notes on vertebrate fossils from late Pleistocene to Holocene of Ryukyu Islands, Japan. Quaternary Research 18: 263–267 (in Japanese with English abstract). Google Scholar

55.

Hasegawa, Y. 2012. Origin of modern mammals in Japan. Mammalian Science 52: 233–247 (in Japanese with English abstract). Google Scholar

56.

Hasegawa, Y., Anezaki, T., Oyama, S., Matsuoka, H. and Chinen, S. 2018. Late Pleistocene mammals from Minatogawa Man Site, Southern Okinawa Island and on the morphological changes of the largest wild boar specimens. Bulletin of Gunma Museum of Natural History 22: 23–49 (in Japanese with English abstract). Google Scholar

57.

Hasegawa, Y., Otsuka, H. and Nohara, A. 1973. Fossil vertebrates from the Miyako Island (Studies of the palaeovertebrates fauna of Ryukyu Islands, Japan. Part I). Memoirs of the National Science Museum 6: 39–52. Google Scholar

58.

Hashimoto, T., Morosawa, T. and Fukasawa, K. 2016. Surprising the world from Amami: mongoose control project in Amami-Oshima Island, the largest extinction in the world. In( Mizuta, T., ed.) Natural History of the Amami Island Group: Biodiversity of Subtropical Islands, pp. 290–312. Tokai University Press, Hiratsuka (in Japanese). Google Scholar

59.

Hayaishi, S. 2011. Human-nature interactions in Amami and Okinawa as seen in modern statistical records. In( Yumoto, T., Tajima, Y. and Ankei, Y., eds.) The Japanese Archipelago Over 35,000 Years: An Environmental History of Humans and Nature—Islands, Forests, and Seas, pp. 197–223. Bun-Ichi Sogo Shuppan, Tokyo (in Japanese). Google Scholar

60.

Hayashi, S., Kondo, K., Araki, K., Sawanaka, I., Mikami, K., Izawa, M. and Kubo, M. O. 2025. Bone histology reveals the slow life history and skeletal adaptations of the Amami rabbit Pentalagus furnessi (Lagomorpha: Mammalia). Mammal Study 50: in press. Google Scholar

61.

Hayashi, S. and Kubo, M. O. 2025. Bone histology suggests insularity and sex differences in Japanese sika deer growth (Cervus nippon). Mammal Study 50: in press. Google Scholar

62.

Hayashida, S., Otsuka, J. and Nishinakagawa, H. 1967. Observations on the bones of Pentalagus furnessi in comparison with those of Oryctolagus cuniculus. Journal of Mammalogical Society of Japan 3: 109–117 (in Japanese with English abstract). Google Scholar

63.

Higashi, T. and Kobayashi, S. 2023. A record of predation of a juvenile Ryukyu long-furred rat Diplothrix legata (Muridae: Rodentia) by a jungle crow Corvus macrorhynchos (Corvidae: Passeriformes) and related nest movement. Mammal Study 48: 137–141. Google Scholar

64.

Higashi, T. and Kobayashi, S. 2025. Record of the nesting process of the Ryukyu long-furred rat Diplothrix legata (Rodentia: Muridae) and newborn predation by the Habu snake Protobothrops flavoviridis (Squamata: Viperidae). Mammal Study 50: in press. Google Scholar

65.

Hiragi, T., Kimoto, Y. and Iwamoto, C. 2017. Road-kills of the Amami rabbit Pentalagus furnessi on Amami-Ohshima Island from April 2007 to March 2017. Mammalian Science 57: 249–265 (in Japanese with English abstract). Google Scholar

66.

Hiragi, T., Shinmura, A. and Suyama, S. 2024. A case of Amami rabbit breeding in school of Yamato Village, Amami Oshima. Journal of Island Studies 25: 83–109 (in Japanese with English abstract). Google Scholar

67.

Hisashi, N., Takanashi, O., Yamashita, K. and Hiragi, T. 2021. Amami Museum Official Guidebook: Nature, History and Culture of Amami as Known from the Museum. Nanpou Shinsha, Kagoshima, 283 pp. (in Japanese). Google Scholar

68.

Hodgson, B. H. 1836. Synoptical description of sundry new animals, enumerated in the Catalogue of Nipalese Mammals. Journal of the Asiatic Society of Bengal. 5: 231–238. Google Scholar

69.

Hoffmann, R. S. and Smith, A. T. 2005. Order Lagomorpha. In( Wilson, D. E. and Reeder, D. M., eds.) Mammal Species of the World: A Taxonomic and Geographic Reference, Third edition, pp. 185–211. The Johns Hopkins University Press, Baltimore. Google Scholar

70.

Hokama, M. 1986. History and Culture of Okinawa. Chuokoron-Shinsha, Tokyo, 248 pp. (in Japanese). Google Scholar

71.

Hokama, M. and Hateruma, E. (eds.). 1997. Ryukyu Koku Yurai Ki (Definitive Edition of the Ryukyu Kingdom Origins Record). Kadokawa, Tokyo, 690 pp. (in Japanese). Google Scholar

72.

Hutterer, R. 2005. Order Soricomorpha. In( Wilson, D. E. and Reeder, D. M., eds.) Mammal Species of the World: A Taxonomic and Geographic Reference, Third edition. pp. 220–311. The Johns Hopkins University Press, Baltimore. Google Scholar

73.

Ikeda, T. and Yamada, F. 2011. Measures against invasive mammals abroad: learning from developed countries. In( Yamada, F., Ikeda, T. and Ogura, G. eds.) Invasive Alien Mammals in Japan: Biology of Control Strategy and Conservation, pp. 59–101. University of Tokyo Press, Tokyo, (In Japanese). Google Scholar

74.

Iki, I. 2021. “Ryucyuguo” in 7th century's “Suisyu” is Okinawa Island. Regional Studies of Okinawa University 26: 29–38 (in Japanese). Google Scholar

75.

Imaizumi, Y. 1967. A new genus and species of cat from Iriomote, Ryukyu Islands. Journal of the Mammalogical Society of Japan 3: 75–105. Google Scholar

76.

Imaizumi, Y. 1973. Taxonomic study of the wild boar from the Ryukyu Islands, Japan. National Science Museum Report 6: 113–114. Google Scholar

77.

Imaizumi, Y. and Takara, T. 1971. External and cranial characters of newborn youngs of the Iriomote wild cat, Mayailurus iriomotensis, with reference to the systematic status. Journal of the Mammalogical Society of Japan 5: 131–135. Google Scholar

78.

Iryu, Y. and Matsuda, H. 2010. The Ryukyu Archipelago, Neogene and Quaternary series. In(Geological Society of Japan, ed.) Regional Geology of Japan, Vol. 8 Kyushu and Okinawa, pp. 149–154. Asakura Publication, Tokyo (in Japanese). Google Scholar

79.

Isaac, N. J., Turvey, S. T., Collen, B., Waterman, C. and Baillie, J. E. 2007. Mammals on the EDGE: conservation priorities based on threat and phylogeny. PLOS ONE 2: e296. https://doi.org/10.1371/journal. pone.0000296Google Scholar

80.

Ishigaki, C., Shinzato, T., Aramoto, Z. and Wu, L. 2007. Feed plant, dressing and utilization of carcass of Ryukyuan wild boar in Iriomote Island. Science Bulletin of the Faculty of Agriculture, University of the Ryukyus 54: 23–27 (in Japanese with English abstract). Google Scholar

81.

Ishiguro, N., Inoshima, Y., Suzuki, K., Miyoshi, T. and Tanaka, T. 2008. Construction of three-year genetic profile of Japanese wild boars in Wakayama Prefecture, to estimate gene flow from crossbred Inobuta into wild boar populations. Mammal Study 33: 43–49. Google Scholar

82.

Ishii, N. 2003. Controlling mongooses introduced to Amami-Oshima Island: a population estimate and program evaluation. Japanese Journal of Conservation Ecology 8: 73–82 (in Japanese with English abstract). Google Scholar

83.

Ito, K., Abe, S., Yamashita, R., Sumiyama, D., Kanazawa, T. and Murata, K. 2020. Prevalence of serum antibodies to Toxoplasma gondii in the small Indian mongoose (Herpestes auropunctatus) on Amami-Oshima Island, Japan. Journal of Veterinary Medical Science 82: 229–231. Google Scholar

84.

IUCN. 2024. The IUCN Red List of Threatened Species. Version 2024.2. Available at  https://www.iucnredlist.org/ (Accessed 30 November 2024). Google Scholar

85.

Iwasa, M. A. 2015a. Tokudaia osimensis (Abe, 1933). In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 165–166. Shoukadoh, Kyoto. Google Scholar

86.

Iwasa, M. A. 2015b. Tokudaia muenninki (Johnson, 1946). In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, p. 168. Shoukadoh, Kyoto. Google Scholar

87.

Iwasa, M. A. 2015c. Tokudaia tokunoshimaensis Endo & Tsuchiya, 2006. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, p. 169. Shoukadoh, Kyoto. Google Scholar

88.

Iwasa, M. A. 2015d. Apodemus agrarius (Pallas, 1771). In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, p. 172. Shoukadoh, Kyoto. Google Scholar

89.

Iwasa, M. A. 2015e. Diplothrix legata (Thomas, 1906). In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, p. 183. Shoukadoh, Kyoto. Google Scholar

90.

Iwasa, M. A. 2015f. Mus caroli Bonhote, 1902. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, p. 184. Shoukadoh, Kyoto. Google Scholar

91.

Iwasa, M. A., Kaneko, Y. and Kawada, S. 2020. Notes on forefoot characteristics of the Ryukyu long-furred rat, Diplothrix legata, for its arboreal lifestyle. Mammal Study 45: 253–258. Google Scholar

92.

Izawa, M. 2015. The feral cat (Felis catus Linnaeus, 1758) as a free-living pet for humans and an effective predator, competitor, and disease carrier for wildlife. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 238–239. Shoukadoh, Kyoto. Google Scholar

93.

Izawa, M., Doi, T., Nakanishi, N. and Teranishi, A. 2009. Ecology and conservation of two endangered subspecies of the leopard cat (Prionailurus bengalensis) on Japanese islands. Biological Conservation 142: 1884–1890. Google Scholar

94.

Izawa, M. and Nakanishi, N. 2018. Iriomote cat and Tsushima leopard cat—Insular populations of Felidae. In( Masuda, R., ed.) Carnivores in Japan: Mammals at the Top of the Ecosystem, pp. 246–265, University of Tokyo Press, Tokyo (in Japanese). Google Scholar

95.

Izawa, M. and Yamada, F. 2023. Studies on mammals in subtropical ecosystems. In(Mammal Society of Japan, ed.) Mammalogy of Japan: Our Centennial Advances, pp. 360–375. Buneido Shuppan, Tokyo (in Japanese). Google Scholar

96.

Jogahara, T. 2016. Rodents in the Ryukyu Archipelago: Tokudaia and Diplothrix legata. In( Motokawa, M., ed.) Mice and Rats in Japan: Their Diversity and Evolution, pp. 169–184. University of Tokyo Press, Tokyo (in Japanese). Google Scholar

97.

Jogahara, T. and Koshimoto, C. 2017. A distribution survey of the endangered rat species Diplothrix legata in Tokunoshima Island, Japan. Mammalian Science 57: 211–215 (in Japanese with English abstract). Google Scholar

98.

Jogahara, T., Nakaya, M., Ikemura, S., Koshimoto, C., Sakamoto, S., Hashimoto, T., Mitani, T., Kuroiwa, M. and Yamada, F. 2020. Records and distribution of the endangered Tokunoshima spiny rat Tokudaia tokunoshimensis on Tokunoshima Island, Japan, from 2005 to 2016. Mammalian Science 60: 105–116 (in Japanese with English abstract). Google Scholar

99.

Jogahara, T., Ogura, G., Sasaki, T., Takehara, K. and Kawashima, Y. 2003. Food habits of cats (Felis catus) in forests and villages and their impacts on native animal in the Yambaru area, northern part of Okinawa Island, Japan. Mammalian Science 43: 29–37 (in Japanese with English abstract). Google Scholar

100.

Johnson, D. H. 1946. The spiny rats of the Riu Kiu Islands. Proceedings of the Biological Society of Washington 59: 169–172. Google Scholar

101.

Johnson, W. E., Ashiki, F. S., Raymond, M. M., Driscoll, C., Leh, C., Sunquist, M., Johnston, L., Wildt, D., Bush, M., Yuhki, N., et al. 1999. Molecular genetic characterization of two insular Asian cat species, Bornean bay cat and Iriomote cat. In( Wasser S. P., ed.) Evolutionary Theory and Process: Modern Perspecitves, Papers in Honor of Eviatar Nevo, pp. 223–248. Kluwer Academic Press, Dordrecht. Google Scholar

102.

Kagoshima Prefectural Office. 2022. Management Plan for Designated Type II Wildlife (Wild Boar), Fourth Phase Plan. Kagoshima Prefectural Office, Kagoshima, 20 pp. Available at  https://www.pref.kagoshima.jp/ad04/documents/98064_20220329152639-1.pdf (Accessed 30 November 20224) (in Japanese). Google Scholar

103.

Kaneko, Y. 2001. Morphological discrimination of the Ryukyu spiny rat (genus Tokudaia) between the islands of Okinawa and Amami Oshima, in the Ryukyu Islands, southern Japan. Mammal Study 26: 17–33. Google Scholar

104.

Kaneko, Y. 2006. The Taxonomy of Japanese Muridae (Mammalia, Rodentia): From the View Point of Biogeography. University of Tokyo Press, Tokyo, 302 pp. Google Scholar

105.

Kaneko, Y. and Murakami, O. 1996. The history of taxonomy in Japanese small rodents. Mammalian Science 36: 109–128. Google Scholar

106.

Kawaguchi, S., Kaneko, Y. and Hasegawa, Y. 2009. A new species of the fossil murine rodent from the Pinza-Abu Cave, the Miyako Island of the Ryukyu Archipelago, Japan. Bulletin of Gunma Museum of Natural History 13: 15–28. Google Scholar

107.

Kawai, K. 2015a. Pipistrellus abramus (Temminck, 1984). In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp 82–84. Shoukadoh, Kyoto. Google Scholar

108.

Kawai, K. 2015b. Myotis pruinosus Yoshiyuki, 1971. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 114–115. Shoukadoh, Kyoto. Google Scholar

109.

Kawai, K. 2015c. Myotis yanbarensis Maeda & Matsumura, 1998. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, p. 116. Shoukadoh, Kyoto. Google Scholar

110.

Kawai, K. 2015d. Murina ryukyuana Maeda & Matsumura, 1998. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 120–121. Shoukadoh, Kyoto. Google Scholar

111.

Kawai, K., Nikaido, M., Harada, M., Matsumura, S., Lin, L.-K., Wu, Y., Hasegawa, M. and Okada, N. 2003. The status of the Japanese and East Asian bats of the genus Myotis (Vespertilionidae) based on mitochondrial sequences. Molecular Phylogenetics and Evolution 28: 297–307. Google Scholar

112.

Kawamura, Y. 1989. Quaternary rodent faunas in the Japanese Islands (Part 2). Memoirs of the Faculty of Science, Kyoto University, Series of Geology and Mineralogy 54: 1–235. Google Scholar

113.

Kawamura, A., Chang, C.-H. and Kawamura, Y. 2016. Middle Pleistocene to Holocene mammal faunas of the Ryukyu Islands and Taiwan: an updated review incorporating results of recent research. Quaternary International 397: 117–135. Google Scholar

114.

Kawauchi, N., Nakamura, Y. and Watanabe, T. 2018. Predation of the endangered Miyako grass lizard Takydromus toyamai by the introduced Japanese weasel Mustela itatsi. Mammalian Science 58: 73–77 (in Japanese with English abstract). Google Scholar

115.

Kazato, K., Watari, Y. and Miyashita, T. 2020. Identification of the population source of free-ranging cats threatening endemic species on Tokunoshima Island, Japan. Mammal Research 65: 719–727. Google Scholar

116.

Kerr, R. 1792. The Animal Kingdom or Zoological System of the Celebrated Sir Charles Linnaeus. Class I. Mammalia. A. Strahan and T. Cadell, Edinburgh and London, 644 pp. Google Scholar

117.

Kimura, M. 2002. Formation of the Ryukyu Archipelago and paleo-geography. In( Kimura, M., ed.) Formation of the Ryukyu Archipelago and Migration of Biota, pp. 19–54. Okinawa Times, Naha (in Japanese). Google Scholar

118.

Kinjo, K. 2015. Pteropus loochoensis Gray, 1870. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, p. 54. Shoukadoh, Kyoto. Google Scholar

119.

Kinjo, K. and Nakamoto, A. 2015. Pteropus dasymallus Temminck, 1825. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 52–53. Shoukadoh, Kyoto. Google Scholar

120.

Kinoshita, G., Suda, K., Aoki, D., Ohnishi, N., Jogahara, T., Sato, J. J., Yamada, F. and Suzuki, H. 2025. Island population dynamics since the Late Miocene; comparative phylogeography of mammalian species in three genera (Pentalagus, Diplothrix, and Tokudaia) endemic to the Central Ryukyu Islands. Mammal Study 50. https://doi.org/10.3106/ms2024-0045Google Scholar

121.

Kirino, M. 1977. The Living Fossil Amami Rabbit. Chobunsha, Tokyo, 214 pp. (in Japanese). Google Scholar

122.

Kitchener, A., Breitenmoser-Würsten, C., Eizirik, E., Gentry, A., Werdelin, L., Wilting, A. and Yamaguchi, N. 2017. A revised taxonomy of the Felidae. Cat News 11: 3–79. Google Scholar

123.

Kizaki, K. and Oshiro, I. 1980. The origin of the Ryukyu Archipelago. In( Kizaki, K., ed.) Natural History of Ryukyu, pp. 8–37. Tsukiji Shokan, Tokyo. (in Japanese). Google Scholar

124.

Kobayashi, S., Kinjo, M., Nakachi, M., Izawa, M., Nakaya, Y. and Nagamine, T. 2022. Distribution and food habits of the introduced Japanese weasel Mustela itatsi (Mammalia: Carnivora: Mustelidae) on Minamidaitojima Island in the Ryukyu Archipelago. Biological Magazine, Okinawa 60: 43–52 (in Japanese with English abstract). Google Scholar

125.

Kobayashi, S., Kinjo, T., Kuroda, Y., Kinjo, M., Okawara, Y., Izawa, M., Onuma, M., Haga, A., Nakaya, Y. and Nagamine, T. 2020. Predation on endangered species by cats in the northern forests of Okinawa-jima Island, Japan. Mammal Study 45: 63–70. Google Scholar

126.

Kobayashi, S., Kotaka, N., Nakata, K. and Takashima, A. 2022. Mammal and bird species using cavities among forests of different ages on Okinawajima Island in the Ryukyu Archipelago, Japan. Journal of Forest Research 27: 439–449. Google Scholar

127.

Kobayashi, S., Sato, Y. and Izawa, M. 2025. Omnivorous food habits of the endangered Ryukyu long-furred rat Diplothrix legata (Muridae) estimated using the DNA metabarcoding method. Mammal Study 50. https://doi.org/10.3106/ms2024-0007Google Scholar

128.

Kobayashi, S., Tamura, H., Maeda, K. and Izawa, M. 2022. First record of the black-bearded tomb bat Taphozous melanopogon Temminck, 1841 (Chiroptera: Emballonuridae) from Japan. Mammal Study 47: 261–264. Google Scholar

129.

Kodera, Y. 2015. Sus scrofa Linnaeus, 1758. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 312–313. Shokado, Kyoto. Google Scholar

130.

Kotaka, N., Yasuda, M. and Shimada, T. 2021. Development of a camera-installed nest box for small mammals and its application in reproductive schedule estimation for the Okinawa spiny rat. Mammal Study 47: 77–85. Google Scholar

131.

Kreiner, Y. and Tabata, C. 1992. Amami in the Meiji Era as seen by a German. Hirugi-sha, Naha, 226 pp. (in Japanese). Google Scholar

132.

Kubo, M. O., Araki, K., Winkler, D. E., Kondo, K. and Hayashi, S. 2025. Feeding ecology of the Amami rabbit (Pentalagus furnessi) and the Ryukyu long-furred rat (Diplothrix legata) inferred from dental microwear texture analysis. Mammal Study 50: in press. Google Scholar

133.

Kubo, M. O., Nakashima, T., Honda, T., Kochi, Y., Ito, Y., Hattori, S. and Kuraishi, T. 2013. Histopathological examination of spontaneous lesions in Amami rabbits (Pentalagus furnessi): a preliminary study using formalin-fixed archival specimens. Japanese Journal of Zoo and Wildlife Medicine 18: 65–70 (in Japanese with English abstract). Google Scholar

134.

Kudaka, N. and Kudaka, M. 2017a. Food habits and habitat of the Ryukyu long-furred rat in Yambaru forest, northern Okinawa Island. Mammalian Science 57: 195–202 (in Japanese with English abstract). Google Scholar

135.

Kudaka, N. and Kudaka, M. 2017b. Okinawa spiny rat is diurnal in summer and nocturnal in winter. Mammalian Science 57: 235–239 (in Japanese with English abstract). Google Scholar

136.

Kueffer, C., Drake, D. and Fernández-Palacios, J. M. 2016. Island biology. Oxford Bibliographies. https://doi.org/10.1093/obo/9780199830060-0149Google Scholar

137.

Kuroda, N. 1921. On three new mammals from Japan. Journal of Mammalogy 2: 208–211. Google Scholar

138.

Kuroda, N. 1924. On new mammals from the Riu Kiu Islands and the vicinity. In( Kuroda, N., ed.) On New Mammals from the Riu Kiu Islands and The Vicinity/On An Apparently New Form of Ural Owl from the Pacific Side of Hondo, Japan, pp. 1–14. Publishedby Nagamichi Kuroda, Tokyo. Google Scholar

139.

Kuroda, N. 1933. A revision of the genus Pteropus found in the islands of the Riu Kiu Chain, Japan. Journal of Mammalogy 14: 312–316. Google Scholar

140.

Kuroda, N. 1940. Monograph Japanese Mammals. Sanseido, Tokyo, 311 pp. (in Japanese). Google Scholar

141.

Kuroiwa, A. 2015. Unique and interesting sex chromosome evolution in Tokudaia. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 166–167. Shoukadoh, Kyoto. Google Scholar

142.

Kyan, H., Matsubara, R. and Nagamune, K. 2013. Toxoplasmosis and the prevalence of Toxoplasma in Okinawa Prefecture. Journal of Antibacterial and Antifungal Agents 41: 19–28. Google Scholar

143.

Kyan, H., Takara, T., Taira, K. and Obi, T. 2021. Toxoplasma gondii antibody prevalence and isolation in free-ranging cats in Okinawa, Japan. Journal of Veterinary Medical Science 83: 1303–1305. Google Scholar

144.

Leyhausen, P. and Pfleiderer, M. 1994. The taxonomic status of the Iriomote cat. Cat News 21: 18–20. Google Scholar

145.

Leyhausen, P. and Pfleiderer, M. 1999. The systematic status of the Iriomote cat (Prionailurus iriomotensis Imaizumi 1967) and the subspecies of the leopard cat (Prionailurus bengalensis Kerr 1792). Journal of Zoological Systematics and Evolutionary Research 37: 121–31. Google Scholar

146.

Li, G., Jones, G., Rossiter, S. J., Chen, S. F., Parsons, S. and Zhang, S. 2006. Phylogenetics of small horseshoe bats from East Asia based on mitochondrial DNA sequence variation. Journal of Mammalogy 87: 1234–1240. Google Scholar

147.

Linnaeus, C. 1758. Systema Naturae: Per Regna Tria Naturae, Secundum Classes, Ordines, Genera, Species, Cum Characteribus, Differentiis, Synonymis, Locis, 1, 10th reformed edition. Impensis Laurentii Salvii, Holmiae, 483 pp. Google Scholar

148.

Linnaeus, C. 1766. Systema Naturae: Per Regna Tria Naturae, Secundum Classes, Ordines, Genera, Species, Cum Characteribus, Differentiis, Synonymis, Locis, 1, 12th edition. Impensis Laurentii Salvii, Holmiae, 532 pp. Google Scholar

149.

Lowe, S., Browne, M., Boudjelas, S. and de Poorter, M. 2000. 100 of the World's Worst Invasive Alien Species: A selection from the Global Invasive Species Database. The Invasive Species Specialist Group (ISSG) of IUCN, Auckland, 12 pp. Google Scholar

150.

Lyon, M. W. 1904. Classification of the hares and their allies. Smithsonian Miscellaneous Collections 45: 321–447. Google Scholar

151.

MacArthur, R. and Wilson, E. O. 2001. The Theory of Island Biogeography, Reprint edition. Princeton University Press, Princeton, 220 pp. Google Scholar

152.

Machida, H., Ota, Y., Kawana, T., Moriwaki, H. and Nagaoka, S. 2001. The Geography of Japan 7: Kyushu and the Nansei-Shoto Islands. University of Tokyo Press, Tokyo, 380 pp. (in Japanese). Google Scholar

153.

Maeda, K. 1996. Review and classification of bat species in Japan. Mammalian Science 36: 1–23. Google Scholar

154.

Maeda, K. and Matsumura, A. 1998. Two new species of Vespertilionid bats, Myotis and Murina (Vespertilionidae: Chiroptera) from Yanbaru, Okinawa Island, Okinawa Prefecture, Japan. Zoological Science 15: 301–307. Google Scholar

155.

Maeda, T., Nakashita, R., Shionosaki, K., Yamada, F. and Watari, Y. 2019. Predation on endangered species by human-subsidized domestic cats on Tokunoshima Island. Scientific Report 9: 16200. https://doi.org/10.1038/s41598-019-52472-3www.nature.com/scientificreportsGoogle Scholar

156.

Makino, T. 2020. Observational records of the Ryukyu long-furred rat on Amami-Oshima Island. Yamashigi: Quarterly of the Amami Ornithologists' Club 123: 5–12 (in Japanese). Google Scholar

157.

Mameno, K., Kubo, T. and Suzuki, M. 2017. Social challenges of spatial planning for outdoor cat management in Amami Oshima Island, Japan. Global Ecology and Conservation 10: 184–193. Google Scholar

158.

Maruta, Y., Nakaya, Y., Nagamine, T., Kinjo, M., Takahashi, Y., Onuma, M., Ishikawa, I., Shiino, F., Nakata, K. and Kotaka, N. 2024. The first record of a road-killed Okinawa spiny rat (Tokudaia muenninki). Mammalian Science 64: 227–232 (in Japanese with English abstract). Google Scholar

159.

Masuda, R. and Yoshida, M. C. 1995. Two Japanese wildcats, the Tsushima cat and the Iriomote cat, show the same Mitochondrial DNA lineage as the leopard cat Felis bengalensis. Zoological Science 12: 655–659. Google Scholar

160.

Masuda, R., Yoshida, M. C., Shinyashiki, F. and Bando, G. 1994. Molecular phylogenetic status of the Iriomote cat Felis iriomotensis, inferred from Mitochondrial DNA sequence analysis. Zoological Science 11: 597–604. Google Scholar

161.

Masuda, R. and Watanabe, S. 2015. Mustela itatsi Temminck, 1844. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 248–249. Shoukadoh, Kyoto. Google Scholar

162.

Matsumoto, H. 1926. On some new fossil cervicorns from Kazusa and Liukiu. Science Reports of the Tohoku Imperial University Ser.2 (Geology) 10: 17–25. Google Scholar

163.

Matsuoka, H. 2000. The Late Pleistocene fossil birds of the Central and Southern Ryukyu Islands, and their zoogeographical implications for recent avifauna of the archipelago. Tropics 10: 165–188. Google Scholar

164.

Matsuzaki, T., Suzuki, H. and Kamiya, M. 1989. Laboratory rearing of the Amami rabbits (Pentalagus furnessi Stone, 1900) in captivity. Experimental Animals 38: 65–69. Google Scholar

165.

Matthee, C. A., van Vuuren, B. J., Bell, D. and Robinson, T. J. 2004. A molecular supermatrix of the rabbits and hares (Leporidae) allows for the identification of five international exchange during the Miocene. Systematic Biology 53: 433–447. Google Scholar

166.

Miller, G. S. 1903. Mammals collected by Dr. W. L. Abbott on the coast and islands of northwest Sumatra. Proceedings of the United States National Museum 26: 437–483. Google Scholar

167.

Ministry of the Environment. 2015. Invasive Alien Species' List to Prevent Ecological Damage (List of Invasive Alien Species That May Threaten Ecosystems and Other Environments in Japan). Available at  https://www.ensv.go.jp/nature/intro/2outline/iaslist.html/ (Accessed 30 November 2024) (in Japanese). Google Scholar

168.

Ministry of the Environment. 2017. On the Ex situ Conservation Program for Spiny Rats Tokudaia. Available at  https://www.env.go.jp/press/103648.html/ (Accessed 30 November 2024) (in Japanese). Google Scholar

169.

Ministry of the Environment. 2018. Feral Cat Management Plan for Ecosystem Conservation on Amami-Oshima Island. Available at  https://www.env.go.jp/content/900492038.pdf/ (Accessed 30 November 2024) (in Japanese). Google Scholar

170.

Ministry of the Environment. 2020. Red List 2020 Threatened Wildlife of Japan, Mammalia. Available at  https://www.env.go.jp/content/900515981.pdf (Accessed 30 November 2024) (in Japanese). Google Scholar

171.

Ministry of the Environment. 2021. Invasive Species in the Amami and Okinawa Region and Their Control Measures. Okinawa-Amami Natural Environment Office, Ministry of the Environment, Naha, 10 pp. (in Japanese). Google Scholar

172.

Ministry of the Environment. 2023. Cat Management and Coexistence Action Plan for Ecosystem Conservation in the Northern Okinawa Island. Available at  https://www.pref.okinawa.jp/_res/projects/default_project/_page_/001/026/836/nekoactionplan.pdf/ (Accessed 30 November 2024) (in Japanese). Google Scholar

173.

Ministry of the Environment. 2024. Declaration of the Eradication of the Small Indian Mongoose (designated an invasive alien species) on Amami-Oshima Island. Available at  https://www.env.go.jp/en/press/press_03205.html (Accessed 30 November 2024) (in Japanese). Google Scholar

174.

Misonne, X. 1969. African and Indo-Australian Muridae: evolutionary trend. Annual Museum Royal de 1'Afrique Centrale, Tervuren, Sciences Zoologique 172: 1–219. Google Scholar

175.

Miyamoto, A., Tanahara, S. and Watari, Y. 2021. Landscape features of endangered Ryukyu long-furred rat (Diprothrix legata) roadkill sites in Yambaru, Okinawa-jima Island. Journal of Forest Research 26: 201–207. Google Scholar

176.

Motokawa, M. 1998. Reevaluation of the Orii's shrew, Crocidura dsinezumi orii Kuroda, 1924 (Insectivora, Soricidae) in the Ryukyu Archipelago, Japan. Mammalia 62: 259–267. Google Scholar

177.

Motokawa, M. 2000. Biogeography of living mammals in the Ryukyu Islands. Tropics 10: 63–71. Google Scholar

178.

Motokawa, M. 2003. Geographic variation in the Japanese white-toothed shrew Crocidura dsinezumi. Acta Theriologica 48: 145–156. Google Scholar

179.

Motokawa, M. 2015a. Crocidura watasei Kuroda, 1924. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 21–22. Shoukadoh, Kyoto. Google Scholar

180.

Motokawa, M. 2015b. Crocidura orii Kuroda, 1924. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, p. 25. Shoukadoh, Kyoto. Google Scholar

181.

Motokawa, M. 2015c. Suncus murinus (Linnaeus, 1766). In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, p. 26–27. Shoukadoh, Kyoto. Google Scholar

182.

Motokawa, M. 2017. “Land emergence” and “elevation shift” affect diversification: a new perspective toward understanding the high species diversity of terrestrial animals in Japan. In( Motokawa, M. and Kajihara, H., eds.) Species Diversity of Animals in Japan, pp. 3–23. Springer Japan, Tokyo. Google Scholar

183.

Motokawa, M., Hattori, S., Ota, H. and Hikida, T. 1996. Geographic variation in the Watase's shrew Crocidura watasei (Insectivora, Soricidae) from the Ryukyu Archipelago, Japan. Mammalia 60: 243–254. Google Scholar

184.

Motokawa, M., Lin, L.-K., Cheng, H.-C. and Harada, M. 2001. Taxonomic status of the Senkaku mole, Nesoscaptor uchidai, with special reference to variation in Mogera insularis from Taiwan (Mammalia: Insectivora). Zoological Science 18: 733–740. Google Scholar

185.

Motokawa, M., Lin, L.-K. and Motokawa, J. 2003. Morphological comparison of Ryukyu mouse Mus caroli (Rodentia: Muridae) populations from Okinawajima and Taiwan. Zoological Studies 42: 258–267. Google Scholar

186.

Motokawa, M. and Maeda, K. 2002. Preserved paratypes of Kuroda's (1924) Ryukyu mammals. Mammal Study 27: 145–147. Google Scholar

187.

Murakami, K., Yoshikawa, S., Konishi, S., Ueno, Y., Watanabe, S. and Mizoguchi, Y. 2014. Evaluation of genetic introgression from domesticated pigs into the Ryukyu wild boar population on Iriomote Island in Japan. Animal Genetics 45: 517–523. Google Scholar

188.

Murata, C., Yamada, F., Kawauchi, N., Matsuda, Y. and Kuroiwa, A. 2012. The Y chromosome of the Okinawa spiny rat, Tokudaia muenninki, was rescued through fusion with an autosome. Chromosome Research 20: 111–125. Google Scholar

189.

Musser, G. G. and Boeadi. 1980. A new genus of Murid rodent from the Komodo Islands in Nusatenggara, Indonesia. Journal of Mammalogy 61: 395–413. Google Scholar

190.

Musser, G. G. and Carleton, M. D. 1993. Family Muridae. In( Wilson, D. E. and Reeder, D. M., eds.) Mammal Species of the World: A Taxonomic and Geographic Reference, Second edition, pp. 501–755. Smithsonian Institution Press, Washington and London. Google Scholar

191.

Musser, G. G. and Carleton, M. D. 2005. Superfamily Muroideas. In( Wilson, D. E. and Reeder, D. M., eds.) Mammal Species of the World: A Taxonomic and Geographic Reference, Third edition, pp. 894–1531. The Johns Hopkins University Press, Baltimore. Google Scholar

192.

Nago, R., Kobayashi, S., Kinjo, T., Ogimi, K., Shinjo, A., Namisato, S., Futamatagawa, A., Higa, G. and Izawa, M. 2019. Seed feeding behavior of Diplothrix legata (Muridae: Rodentia): effects on germination of five plants in Okinawajima Island, Japan. Mammal Study 44: 129–134. Google Scholar

193.

Nagoya, S. ca. 1855. Nanto Zatsuwa (Illustrated Natural History on Amami-Oshima Island). ( Kokubu, N. and Era, H. 1984. New Revised Edition of Nanto Zatsuwa: Ethnography of Amami-Oshima, Volume 1. Heibonsha, Tokyo, 243 pp.) (in Japanese). Google Scholar

194.

Nakama, Y. 2011. A Study on the History of Forest Management Systems in Okinawa, Revised and expanded edition. Media Express, Naha, 369 pp. (in Japanese). Google Scholar

195.

Nakamoto, A. 2017. Temporal changes in distributional range of the Ryukyu flying fox in the Ryukyu Archipelago, Japan. Mammalian Science 57: 267–284 (in Japanese with English abstract). Google Scholar

196.

Nakamoto, A. 2023. Okinawa flying fox, Pteropus loochoensis Gray, 1870. In( Sano, A. and Fukui, D., eds.) Guide to the Bats of Japan, pp. 31–33. Bun-ichi Sougou Shuppan, Tokyo (in Japanese with English abstract). Google Scholar

197.

Nakamoto, A., Itabe, S., Sato, A., Kinjo, K. and Izawa, M. 2011. Geographical distribution pattern and interisland movements of Orii's flying fox in Okinawa Islands, the Ryukyu Archipelago, Japan. Population Ecology 53: 241–252. Google Scholar

198.

Nakamoto, A., Kinjo, K. and Izawa, M. 2012. Ranging patterns and habitat use of a solitary flying fox (Pteropus dasymallus) on Okinawa-jima Island, Japan. Acta Chiropterologica 14: 387–399. Google Scholar

199.

Nakamoto, A., Kinjo, K. and Izawa, M. 2016. Activity patterns of the Ryukyu flying fox on a subtropical island: responses to seasonal changes in night length. Journal of Ethology 34: 321–328. Google Scholar

200.

Nakamura, N., Yoshimoto, K., Suzuki, M., Kawai, K., Akai, K., Oshima, I., Nakanishi, Y. and Takayama, K. 2023. Efficacy of electric fencing in preventing Amami rabbit (Pentalagus furnessi) invasions of agricultural lands. Nihon Chikusan Gakkaiho 94: 61–68 (In Japanese with English abstract). Google Scholar

201.

Nakamura, Y. 2018. Fossil and archeological records of the Ryukyu long-furred rat Diplothrix legata (Rodentia, Muridae). Mammal Study 43: 109–116. Google Scholar

202.

Nakamura, Y. and Ota, H. 2015. Late Pleistocene-Holocene amphibians from Okiawajima Island in the Ryukyu Archipelago, Japan: reconfirmed faunal endemicity and the Holocene range collapse of forest-dwelling species. Palaeontologia Electronica 18: 1–26. Google Scholar

203.

Nakanishi, N. 2023. Morphology and taxonomy. In( Doi, T. and Izawa, M., eds.) The Iriomote Cat, pp. 171–191. University of Tokyo Press, Tokyo (in Japanese). Google Scholar

204.

Nakanishi, N. and Izawa, M. 2015. Prionailurus bengalensis iriomotensis (Imaizumi, 1967). In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 236–237. Shoukadou, Kyoto. Google Scholar

205.

Nakanishi, N. and Izawa, M. 2016. Importance of frogs in the diet of the Iriomote cat based on stomach content analysis. Mammal Research 61: 35–44. Google Scholar

206.

Nakanishi, N., Tsubasaka, Y., Sawanaka, I., Kondo, K., Kobayashi, S., Izawa, M. and Hayashi, S. 2025. An attempt at age estimation of the Ryukyu long-furred rat (Diplothrix legata) using tooth wear analysis: first report on the difference in molar wear patterns between rats in Okinawajima and Amami-Oshima Islands. Mammal Study 50: in press. Google Scholar

207.

Nakano, A. and Murai, Y. 1996. The feral dog Canis familiaris predated on the Ryukyu spinous country-rat Tokudaia osimensis and the Ryukyu long-tailed giant rat Diplothrix legata on the island of Amamiohshima, Kagoshima Prf., Japan. Mammalian Science 36: 53–58 (in Japanese). Google Scholar

208.

Nakaya, Y., Nagamine, T., Kinjo, M., Nakata, K. and Yamamoto, I. 2017. Long-term feeding of rescued Ryukyu long-furred rats and Okinawa spiny rat. Mammalian Science 52: 221–226 (in Japanese with English abstract). Google Scholar

209.

Nature Conservation Society of Japan. 1990. Opinion Statement on the Early Ratification of the World Heritage Convention. Available at  https://what-we-do.nacsj.or.jp/1990/07/8509/ (Accessed 30 November 2024) (in Japanese). Google Scholar

210.

Nishioka, Y., Nakagawa, R., Nunami, S. and Hirasawa, S. 2016. Small mammalian remains from the Late Holocene deposits on Ishigaki and Yonaguni Islands, Southwestern Japan. Zoological Studies 55: 5. https://doi.org/10.6620/zs.2016.55-05Google Scholar

211.

O'Brien, S. J. and Johnson, W. E. 2007. The evolution of cats. Scientific American 297: 68–75. Google Scholar

212.

Ogura, G., Nonaka, Y., Kawashima, M., Sakashita, M., Nakachi, M. and Oda, S. 2001. Relationship between body size and sexual maturation, and seasonal change of reproductive activities in female feral Asian mongoose (Herpestes javanicus) on Okinawa Island. Japanese Journal of Zoo and Wildlife Medicine 6: 7–14. Google Scholar

213.

Ogura, G., Sakashita, M. and Kawashima, Y. 1998. External morphology and classification of mongoose on Okinawa Island. Mammalian Science 38: 259–270 (in Japanese with English abstract). Google Scholar

214.

Ogura, G., Sasaki, T., Toyama, M., Takehara, K., Nakachi, M., Ishibashi, O., Kawashima Y. and Oda, S. 2002. Food habits of the feral small Asian mongoose (Herpestes javanicus) and impacts on native species in the northern part of Okinawa Island. Mammalian Science 42: 53–62 (in Japanese with English abstract). Google Scholar

215.

Ogura, G. and Yamada, F. 2011. Small Indian mongoose: Japan's top priority target species. In( Yamada, F., Ikeda, T. and Ogura, G. eds.) Invasive Alien Mammals in Japan; Biology of Control Strategy and Conservation, pp. 105–137. University of Tokyo Press, Tokyo, (In Japanese). Google Scholar

216.

Ohdachi, S. D., Fujiwara, K., Shekhar, C., Sơn, N. T., Suzuki, H. and Osada, N. 2024. Phylogenetics and population genetics of the Asian house shrew, Suncus murinusS. montanus species complex, inferred from whole-genome and mitochondrial DNA sequences, with special reference to the Ryukyu Archipelago, Japan. Zoological Science 41: 216–229. Google Scholar

217.

Ohdachi, S. D., Hasegawa, M., Iwasa, M. A., Vogel, P., Oshida, T., Lin, L.-K. and Abe, H. 2006. Molecular phylogenetics of soricid shrews (Mammalia) based on mitochondrial cytochrome b gene sequences: with special reference to the Soricinae. Journal of Zoology of London 270: 177–191. Google Scholar

218.

Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T. 2015. The Wild Mammals of Japan, Second edition. Shoukadoh, Kyoto, 506 pp. Google Scholar

219.

Ohnishi, N., Kobayashi, S., Nagata, J. and Yamada, F. 2017. The influence of invasive mongoose on the genetic structure of the endangered Amami rabbit populations. Ecological Research 32: 735–741. Google Scholar

220.

Okada, S., Shoshi, Y., Takashima., Y., Sanjoba, C., Watari, Y. and Miyashita, T. 2022. Role of landscape context in Toxoplasma gondii infection of invasive definitive and intermediate hosts on a World Heritage Island. International Journal for Parasitology: Parasites and Wildlife 19: 96–104. Google Scholar

221.

Okano, T. and Onuma, M. 2015. Morphological variation in the sperm head of Ryukyu long-furred rat, Diplothrix legata. Mammal Study 40: 193–196. Google Scholar

222.

Okano, T., Onuma, M. and Nakata, K. 2015. Evaluation of the genetic diversity of the Ryukyu long-furred rat (Diplothrix legata) on northern Okinawa-jima Island, Japan. Japanese Journal of Zoo and Wildlife Medicine 20: 9–14. Google Scholar

223.

Okinawa Prefectural Office. 2020. Control Plan for the Japanese Weasel Based on the Okinawa Prefecture Invasive Species Management Action Plan. Okinawa Prefectural Office, Naha, 8 pp. Available at  https://www.pref.okinawa.jp/_res/projects/default_project/_page_/001/004/820/05-02nihonnitati.pdf (Accessed 30 November 2024) (in Japanese). Google Scholar

224.

Okinawa Prefectural Office. 2023. Control Plan for Feral Goats Based on the Okinawa Prefecture Invasive Species Management Action Plan. Okinawa Prefectural Office, Naha, 8 pp. Available at  https://www.pref.okinawa.lg.jp/_res/projects/default_project/_page_/001/004/820/noyagiplan.pdf (Accessed 30 November 2024) (in Japanese). Google Scholar

225.

Okinawa Prefectural Office. 2024. U.S. Military Bases on Okinawa Island. Available at  https://www.pref.okinawa.jp/kyoiku/kodomo/1002657/1002668.html/ (Accessed 30 November 2024) (in Japanese). Google Scholar

226.

Oshiro, I. 2002. Quaternary geological history of the Ryukyu Islands and the migration of Animals. In( Kimura, M., ed.) Formation of the Ryukyu Archipelago and Migration of Biota, pp. 129–140. Okinawa Times, Naha (in Japanese). Google Scholar

227.

Ota, H. 2002. Strengths and weaknesses of an approach based on current biology to the reconstruction of Paleogeography: with special reference to the reptiles and amphibians of the Ryukyu Archipelago. In( Kimura, M., ed.) Formation of the Ryukyu Archipelago and Migration of Biota, pp. 175–185. Okinawa Times, Naha (in Japanese). Google Scholar

228.

Ota, H. 2012. Distribution and Paleogeography of terrestrial organisms in the Ryukyu Archipelago and other Nansei shoto Islands—Past trends and future directions. Chikyu Monthly (Earth Monthly) 34: 427–436 (in Japanese). Google Scholar

229.

Otuka, Y. 1941. On the stratigraphic horizon of Elephas from Miyako Is., Ryūkyū Islands, Japan. Proceedings of the Imperial Academy 17(2): 43–47. Google Scholar

230.

Otsuka, H. 2002. Paleo-vertebrate fauna of the Ryukyu Islands and their origins. In( Kimura, M., ed.) Formation of the Ryukyu Archipelago and Migration of Biota, pp. 111–127. Okinawa Times, Naha (in Japanese). Google Scholar

231.

Otsuka, J., Toyomitsu, Y. and Nishinakagawa, H. 1980. Linear measurements of the bones of Lepus brachyurus brachyurus Temminck, Pentalagus furnessi Stone and Oryctolagus cuniculus Linnaeus (JW-NIBS) I. On the Cranium and Ossa truci. Experimental Animals 29: 441–455 (in Japanese with English abstract). Google Scholar

232.

Otsuka, J., Toyomitsu, Y. and Nishinakagawa, H. 1981. Linear measurements of the bones of Lepus brachyurus brachyurus Temminck, Pentalagus furnessi Stone and Oryctolagus cuniculus Linnaeus (JW-NIBS) II. On the Ossa membri thoracici et pelvini. Experimental Animals 30: 113–127 (in Japanese with English abstract). Google Scholar

233.

Ozawa, T. 2009. Origin and formative process of endemic fauna of the Ryukyu Archipelago, viewed from temporal changes of Pleistocene vertebrate fauna. Abstracts with Programs of Regular Meeting of the Palaeontological Society of Japan 158: 5 (in Japanese). Google Scholar

234.

Pallas, P. S. 1771. Reise durch Verscheniden Provinzen des Russichen Reichs. Vol. 1. Imperial Emperor, Academie of Science, St. Petersburg, 454 pp. (in German). Google Scholar

235.

Patel, R. P., Wutke, S., Lenz, D., Mukherjee, S., Ramakrishnan, U., Veron, G., Fickel, J., Wilting, A. and Förster, D. W. 2017. Genetic structure and phylogeography of the leopard cat (Prionailurus bengalensis) inferred from mitochondrial genomes. Journal of Heredity 108: 349–360. Google Scholar

236.

Patou, M.-L., Mclenachan, P. A., Morley, C. G., Couloux, A., Jennings, A. P. and Veron, G. 2009. Molecular phylogeny of the Herpestidae (Mammalia, Carnivora) with a special emphasis on the Asian Herpestes. Molecular Phylogenetics and Evolution 53: 69–80. Google Scholar

237.

Pearson, R. 2013. Ancient Ryukyu: An Aarchaeological Study of Island Communities. University of Hawai‘i Press, Honolulu, 396 pp. Google Scholar

238.

Perry, M. C. 1856a. Narrative of the Expedition of an American Squadron to the China Seas and Japan, Performed in the Years 1852, 1853, and 1854, Volume 1. Beverley Tucker, Senate Printer, New York, 537 pp. Available at  https://www.biodiversitylibrary.org/item/41892#page/7/mode/1up (Accessed 30 November 2024) (Translated from English to Japanese by Miyazaki, H. in 2014. Kadokawa, Tokyo, the First Volume 643 pp. and the Second Volume 570 pp.). Google Scholar

239.

Perry, M. C. 1856b. Narrative of the Expedition of an American Squadron to the China Seas and Japan, Performed in the Years 1852, 1853, and 1854, Volume 2. Beverley Tucker, Senate Printer, New York, 414 pp. Available at  https://www.biodiversitylibrary.org/item/104920#page/11/mode/1up (Accessed 30 November 2024). Google Scholar

240.

Peters, W. 1871. Vesperugo pulveratus, Peters, n. sp. (Grizzled House-bat). Proceedings of the Zoological Society of London 1870: 618–619. Google Scholar

241.

Preble, J. H., Vincenot, C. E., Hill, D. E., and Ohte, N. 2021a. Capturing endangered endemic Okinawan bats with acoustic lures. Journal for Nature Conservation 64: 126074. https://doi.org/10.1016/j.jnc.2021. 126074Google Scholar

242.

Preble, J. H., Vincenot, C. E., Saito, K. and Ohte, N. 2021b. Roosting ecology of endangered plant-roosting bats on Okinawa Island: implications for bat-friendly forestry practices. Ecology and Evolution 11: 13961–13971. Google Scholar

243.

Qi, H., Watari, Y. and Miyashita, T. 2022. A psychological model to understand background reasons for different attitudes and behaviors of youth residents in relation to free-roaming cat problems on a human-inhabited World Heritage Island in Japan. Global Ecology and Conservation 34: e02009. https://doi.org/10.1016/j.gecco. 2022.e02009Google Scholar

244.

Rafinesque, C. S. 1814. Principes Fondamentaux de Somiologie. Palerme, Impr. de F. Abate, aux Dépens de l'Auteur, Paris, 204 pp. (in French). Google Scholar

245.

Ross, J., Brodie, J., Cheyne, S., Hearn, A., Izawa, M., Loken, B., Lynam, A., McCarthy, J., Mukherjee, S., Phan, C., et al. 2015. Prionailurus bengalensis. The IUCN Red List of Threatened Species 2015: e. T18146A50661611. Available at  https://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T18146A50661611.en (Accessed 20 December 2021). Google Scholar

246.

Saito, I. and Takehara, K. 2013a. Ryukyu and Osumi Islands collection journal (1921). In( Masatomi, H. and Kato, K., eds.) The Collection Journal of Wildlife Collector, Hyojiro Orii: The Man Who Supported Ornithology and Mammalogy, pp. 121–225. Hyojiro Orii Research Association, Tomakomai (in Japanese). Google Scholar

247.

Saito, I. and Takehara, K. 2013b. Ryukyu collection journal (1936). In( Masatomi, H. and Kato, K., eds.) The Collection Journal of Wildlife Collector, Hyojiro Orii: The Man Who Supported Ornithology and Mammalogy, pp. 491–517. Hyojiro Orii Research Association, Tomakomai (in Japanese). Google Scholar

248.

Sako, T., Uchimura, M. and Koreeda, Y. 1991. Rearing and reproduction of the Amami rabbit. Animals and Zoos 43: 272–274 (in Japanese). Google Scholar

249.

Sano, A. 2015a. Miniopterus fuscus Bonhote, 1902. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 128–129. Shoukadoh, Kyoto. Google Scholar

250.

Sano, A. 2015b. Tadarida latouchei Thomas, 1920. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, p. 132. Shoukadoh, Kyoto. Google Scholar

251.

Sano, A. and Armstrong, N. 2015a. Rhinolophus cornutus Anderson, 1905. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 61–62. Shoukadoh, Kyoto. Google Scholar

252.

Sano, A. and Armstrong, N. 2015b. Rhinolophus pumilus Anderson, 1905. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 63–64. Shoukadoh, Kyoto. Google Scholar

253.

Sano, A. and Armstrong, N. 2015c. Rhinolophus perditus Anderson, 1918. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 65–66. Shoukadoh, Kyoto. Google Scholar

254.

Sano, A. and Diaz, L. M. E. 2015. Hipposideros turpis Bangs, 1901. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 68–71. Shoukadoh, Kyoto. Google Scholar

255.

Sano, A. and Ishida, M. 2015. Myotis macrodactylus (Temminck, 1840). In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 107–109. Shoukadoh, Kyoto. Google Scholar

256.

Sano, A. and Tamura, T. 2023. Okinawa little horseshoe bat, Rhinolophus pumilus Andersen, 1905. In( Sano, A. and Fukui, D. eds.) Guide to the Bats of Japan, pp. 54–56. Bun-ichi Sougou Shuppan, Tokyo (in Japanese with English abstract). Google Scholar

257.

Sasai, T., Kameda, K. and Izawa, M. 2016. Seasonal changes in predation on sea turtle eggs and use of beaches by the Ryukyu wild boar Sus scrofa riukiuanus on southern Iriomote Island, Japan. Mammalian Science 56: 97–103 (in Japanese with English abstract). Google Scholar

258.

Sato, J. J. 2017. A review of the process of mammalian faunal assembly in Japan: insights from the molecular phylogenetics. In( Motokawa, M. and Kajihara, H., eds.) Species Diversity of Animals in Japan, pp. 49–116. Springer Japan, Tokyo. Google Scholar

259.

Sato, J. J. and Suzuki, H. 2004. Phylogenetic relationships and divergence times of the genus Tokudaia within Murinae (Muridae; Rodentia) inferred from the nucleotide sequences encoding the mitochondrial cytochrome b gene and nuclear recombination-activating gene 1 and interphotoreceptor retinoid-binding protein. Canadian Journal of Zoology 82: 1343–1351. Google Scholar

260.

Sato, T., Watari, Y. and Jogahara, T. 2023. Genetic relationships among populations of the small Indian mongoose (Urva auropunctata) introduced in Japan. Mammal Research 68: 177–187. Google Scholar

261.

Sayre, R., Noble, S., Hamann, S., Smith, R., Wright, D., Breyer, S., Butler, K., van Graafeiland, K., Frye, C., Karagulle, D., et al. 2019. A new 30 meter resolution global shoreline vector and associated global islands database for the development of standardized ecological coastal units. Journal of Operational Oceanography 12: s47–s56. Google Scholar

262.

Sclater, P. L. 1873. Report on the additions to the Society's Menagerie in January 1873. (Plate XXII.). In(Proceedings of the Zoological Society of London, ed.) p. 193. Academic Press, London. Google Scholar

263.

Seki, Y., Nakashima, K. and Nakashima, A. 2023. Habitat selection of endangered Amami rabbits on Tokuno-Shima Island in Japan as assessed by counting fecal pellet groups on roads. Animal Biology 73: 259–272. Google Scholar

264.

Sekiguchi, K., Ogura, G., Sasaki, T., Nagayama, Y., Tsuha, K. and Kawashima, Y. 2002. Food habits of introduced Japanese weasels (Mustela itatsi) and impacts on native species on Zamami Island. Mammalian Science 42: 153–160 (in Japanese with English abstract). Google Scholar

265.

Shimada, T., Aplin, K., Jogahara, T., Lin, K.-L., Gonzalez, J.-P., Herbreteau, V. and Suzuki, H. 2007. Complex phylogeographic structuring in a continental small mammal from East Asia, the rice field mouse, Mus caroli (Rodentia, Muridae). Mammal Study 32: 49–62. Google Scholar

266.

Shimada, T., Iijima, H. and Kotaka, N. 2024. Wild boar population fluctuations in a subtropical forest: the crucial role of mast seeding in Ryukyu Islands, Japan. European Journal of Wildlife Research 70: 41. https://doi.org/10.1007/s10344-024-01797-0Google Scholar

267.

Shinoda, K. and Adachi, N. 2017. Ancient DNA analysis of palaeolithic Ryukyu Islanders. In( Piper, P. J., Matsumura, H. and Bulbeck, D., eds.) New Perspectives in Southeast Asian and Pacific Prehistory, pp. 51–60. The Australian National University Press, Canberra. Google Scholar

268.

Shinohara, A., Yamada, F., Kashimura, A., Abe, S., Sakamoto, S., Morita, T. and Koshimoto, C. 2013. Long-term feeding of the endangered Amami spiny rat (Tokudaia osimensis) under laboratory conditions. Mammalian Science 53: 335–344 (in Japanese with English abstract). Google Scholar

269.

Shionosaki, K. 2016. Feral cats' favorite prey is endangered mammals on Amami-Oshima. In( Mizuta, T., ed.) Natural History of the Amami Island Group: Biodiversity of Subtropical Islands, pp. 271–289. Tokai University Press, Hiratsuka (in Japanese). Google Scholar

270.

Shionosaki, K., Yamada, F., Ishikawa, T. and Shibata, S. 2015. Feral cat diet and predation on endangered endemic mammals on a biodiversity hot spot (Amami-Ohshima Island, Japan). Wildlife Research 42: 343–352. Google Scholar

271.

Shiraishi, S. and Arai, S. 1980. Terrestrial animal survey (2) (primarily mammals). In( Okinawa Development Agency, ed.) Senkaku Islands Survey Report (Academic Research Section), pp. 47–85. Okinawa Development Agency, Tokyo (In Japanese). Google Scholar

272.

Shiraishi, S., Mouri, T. and Uchida, T. 1977. An aberrant form of Apodemus agrarius (Pallas) collected from Uotsuri-jima, the Senkaku Islands, Ryukyus. Zoological Magazine 86: 534 (in Japanese). Google Scholar

273.

Shoshi, Y., Kazato, K., Maeda, T., Takahashi, Y., Watari, Y., Matsumoto, Y., Miyashita, T. and Sanjoba, C. 2021. Prevalence of serum antibodies to Toxoplasma gondii in free-ranging cats on Tokunoshima Island, Japan. Journal of Veterinary Medical Science 83: 333–337. Google Scholar

274.

Simmons, N. B. 2005. Order Chiroptera. In( Wilson D. E. and Reeder D. M., eds.) Mammal Species of the World. A Taxonomic and Geographic Reference, Third edition, pp. 312–529. Johns Hopkins University Press, Baltimore. Google Scholar

275.

Soto, I., Balzani, P., Carneiro, L., Cuthbert, R. N., Macêdo, R., Tarkan, A. S., Ahmed, D. A., Bang, A., Bacela-Spychalska, K., Bailey, S. A., et al. 2024. Taming the terminological tempest in invasion science. Biological Reviews 99: 1357–1390. Google Scholar

276.

Stone, W. 1900. Descriptions of a new rabbit from the Liu Kiu Islands and a new flying squirrel from Borneo. Proceedings of the Academy of Natural Sciences of Philadelphia 52: 460–463. Google Scholar

277.

Suetsugu, K. and Hashiwaki, H. 2023. A non-photosynthetic plant provides the endangered Amami rabbit with vegetative tissues as a reward for seed dispersal. Ecology 104: e3972. https://doi.org/10.1002/ecy.3972Google Scholar

278.

Sugimura, K. 2002. Trends in the population dynamics of birds and the Amami rabbit on Amami-Oshima Island, along with environmental changes. Environmental Information Science 16: 121–126 (in Japanese). Google Scholar

279.

Sugimura, K. and Yamada, F. 2004. Estimating population size of the Amami rabbit Pentalagus furnessi based on fecal pellet counts on Amami Island, Japan. Acta Zoologica Sinica 50: 519–526. Google Scholar

280.

Suzuki, H. 1985. Amami Rabbit Island: Animals of the Forest in Amami Island Group. Shinjuku Shobo, Tokyo, 223 pp. (in Japanese). Google Scholar

281.

Suzuki, H. and Hanihara, K. 1982. The Minatogawa man: the Upper Pleistocene man from the Island of Okinawa. University Museum, The University of Tokyo, Bulletin 19: 7–49. Google Scholar

282.

Suzuki, H., Hosoda, T., Sakurai, S., Tsuchiya, K., Munechika, I. and Korablev, V. P. 1994. Phylogenetic relationship between the Iriomote cat and the leopard cat, Felis bengalensis, based on the ribosomal DNA. Japanese Journal of Genetics 69: 397–406. Google Scholar

283.

Suzuki, H., Tsuchiya, K. and Takezaki, N. 2000. A molecular phylogenetic framework for the Ryukyu endemic rodents Tokudaia osimensis and Diplothrix legata. Molecular Phylogenetics and Evolution 15: 15–24. Google Scholar

284.

Suzuki, M. 2023. Amami rabbit: frequent roadkill accidents on the Natural World Heritage Island. In( Yanagawa, H., Tsukada, H. and Sonoda, Y., eds.) Wildlife Roadkill in Japan: From Wildlife Management to Road Ecology, pp. 136–151. University of Tokyo Press, Tokyo (in Japanese). Google Scholar

285.

Suzuki, M. and Oumi, S. 2017a. A case study of feral cat predation on a weaning juvenile of the Amami rabbit as revealed by a camera trap survey in Amami-Oshima Island in Japan. Mammalian Science 57: 241–247 (in Japanese with English abstract). Google Scholar

286.

Suzuki, M. and Oumi, S. 2017b. Two cases of reproduction and maternal care behavior in the same breeding nest of the Amami rabbit in an orchard in Amami-Oshima Island in Japan. Mammalian Science 57: 257–266 (in Japanese with English abstract). Google Scholar

287.

Swinhoe 1863. On the mammals of the Island of Formosa (China). Proceedings of the Zoological Society of London 8: 347–365. Google Scholar

288.

Takahashi, A., Hasegawa, Y. and Katagiri, C. 2023. Fossil Felidae. In( Doi, T. and Izawa, M., ed.) The Iriomote Cat, pp. 322–348. University of Tokyo Press, Tokyo (in Japanese). Google Scholar

289.

Takahashi, R., Gushiken, R., Nagata, K., Shinzato, A., Sri Kantha, S. and Yasuda, M. 2019. Genetic structure of the Ryukyu wild boar population on Tokunoshima Island (Japan) based on modern and ancient DNA analyses: evidence of recent gene flow from pigs to wild boars. Mammal Study 44: 157–171. Google Scholar

290.

Takamiya, H. 2017. The islands of Amami and Okinawa where hunter-gatherers once throve. Kagoshima University Research Center for The Pacific Island Occasional Papers 58: 1–8. Google Scholar

291.

Takamiya, H. 2021. Prehistory of the Miraculous Islands: Island Culture of the Ryukyu Archipelago in the Prehistoric and Protohistoric Eras. Borderink Press, Naha, 333 pp. (in Japanese). Google Scholar

292.

Takamiya, H., Hudson, M. J., Yonenobu, H., Kurozumi, T. and Toizumi, T. 2016. An extraordinary case in human history: prehistoric hunter-gatherer adaptation to the islands of the Central Ryukyus (Amami and Okinawa archipelagos), Japan. Holocene 26: 408–422. Google Scholar

293.

Takamiya, H., Kin, M. and Suzuki, M. 1975. Excavation report of the Yamashita-cho Cave Site, Naha-shi, Okinawa. Journal of the Anthropological Society of Nippon 83: 125–130 (in Japanese with English abstract). Google Scholar

294.

Takara, T. 1954. Fauna of the Senkaku Island, Ryukyus. Science Bulletin of the College of Agriculture, University of the Ryukyus 1: 57–74 (In Japanese with English abstract). Google Scholar

295.

Taki, Y., Vincenot, C. E., Sato, Y. and Inoue-Murayama, M. 2021. Genetic diversity and population structure in the Ryukyu flying fox inferred from remote sampling in the Yaeyama archipelago. PLOS ONE 16: e0248672. https://doi.org/10.1371/journal.pone.0248672Google Scholar

296.

Takiguchi, M. 2015. Carpa hircus Linnaeus, 1758. In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 318–319. Shoukadoh, Kyoto. Google Scholar

297.

Tamanaha, S., Mukai, S., Yoshinaga, T., Handa, H., Kinjo, T., Nakaya, Y., Nakachi, M., Kinjo, M., Nagamine, T., Nakata, K., et al. 2017. Roadkill risk map for the endangered Ryukyu long-furred rat Diplothrix legata along Prefectural Route 2 on northern Okinawajima Island, Japan. Mammalian Science 57: 203–209 (in Japanese with English abstract). Google Scholar

298.

Tamanaha, S. and Watari, Y. 2023. Ryukyu long-furred rat: roadkill of arboreal mammal. In( Yanagawa, H., Tsukada, H. and Sonoda, Y., eds.) Wildlife Roadkill in Japan: From Wildlife Management to Road Ecology, pp. 152–165. University of Tokyo Press, Tokyo (in Japanese). Google Scholar

299.

Taniguchi, S., Hiragi, T., Kobayashi, S. and Izawa, M. 2019. Report on the observation of the Ryukyu long-furred rat using route censuses in the northern Okinawa-jima Island in 2009 and 2012–2015. Biological Magazine of Okinawa 57: 243–251 (in Japanese with English abstract). Google Scholar

300.

Tawada, M. 1972. Old Feudal Era. Forestry in Okinawa, Naha, 20 pp. (in Japanese). Google Scholar

301.

Temminck, C. J. 1825. Monographies de Mammalogie, ou Description de Quelques Genres de Mammifères, dont les Espèces ont été Observées dans les Différens Musées de l'Europe. G. Dufour et E. d'Ocagne, Paris, 268 pp. (in French). Google Scholar

302.

Temminck, C. J. 1834. Over een geslack der vleugelhandige zoogdieren. Tijdschrift voor Natuurlijke Geschiedenis en Physiologie 1: 1–30 (in Dutch). Google Scholar

303.

Temminck, C. J. 1835–1841. Monographies de Mammalogie, ou Description de Quelques Genres de Mammifères, dont les Espèces ont été Observées dans les Différens Musées de l'Europe. Vol. II. G. Dufour et E. d'Ocagne, Paris, 392 pp. (in French). Google Scholar

304.

Temminck, C. J. 1842–1844. Aperçu général et spécifique sur les mammiféres qui habitent le japon et les iles qui endépendent. In( de Siebold, P. F., Temminck, C. J. and Schlegel, H., eds.) Fauna Japonica, pp. 1–59, pls 1–20. Arnz et Socii, Lugduni Batavorum (in French). Google Scholar

305.

Terao, M., Ogawa, Y., Takada, S., Kajitani, R., Okuno, M., Mochimaru, Y., Matsuoka, K., Itoh, T., Toyoda, A., Kono, T., et al. 2022. Turnover of mammal sex chromosomes in the Sry-deficient Amami spiny rat is due to male-specific upregulation of Sox 9. Proceedings of the National Academy of Sciences (PNAS) 119: e22115741. https://doi.org/10.1073/pnas.2211574119Google Scholar

306.

Tershy, B. R., Shen, K.-W., Kelly, M., Newton, K. M., Holmes, N. D. and Croll, D. A. 2015. The importance of islands for the protection of biological and linguistic diversity. BioScience 65: 592–597. Google Scholar

307.

Thomas, O. 1906. On a second species from the Liu Kiu Islands. Annals and Magazine of Natural History, Series 7, 17: 88–89. Google Scholar

308.

Thomas, O. 1916. On Muridae from Darjiling and the Chin Hills. Journal of the Bombay Natural History Society 24: 404–415. Google Scholar

309.

Thomas, O. 1920. Two new Asiatic bats of the genera Tadarida and Dyacopterus. Annals and Magazine of Natural History; Zoology, Botany, and Geology, Series 9, 5: 283–285. Google Scholar

310.

Thong, V. D., Puechmaille, S. J., Denzinger, A., Bates, P. J. J., Dietz, C., Csorba, G., Soisook, P., Teeling, E. C., Matsumura, S., Furey, N. M., et al. 2012. Systematics of the Hipposideros turpis complex and a description of a new subspecies from Vietnam. Mammal Review 42: 166–192. Google Scholar

311.

Tobe, A., Sato, Y., Wachi, N., Nakanishi, N. and Izawa, M. 2024. Seasonal diet partition among top predators of a small island, Iriomotejima Island in the Ryukyu Archipelago, Japan. Scientific Reports 14: 7727. https://doi.org/10.1038/s41598-024-58204-6Google Scholar

312.

Toizumi, T. 2018. Use of animal resources in Amami and Okinawa as seen from excavated vertebrate remains. In( Takamiya, H., ed.) Frontier of Prehistoric Studies in the Amami and Okinawa Islands, pp. 109–128, Nanpou Shinsha, Kagoshima (in Japanese). Google Scholar

313.

Tokiwa, T., Yoshimura, H., Hiruma, S., Akahori, Y., Suzuki, A., Ito, K., Yamamoto, M. and Ike, K. 2019. Toxoplasma gondii infection in Amami spiny rat on Amami-Oshima Island, Japan. Parasites and Wildlife 9: 244–247. Google Scholar

314.

Tokuda, M. 1941. A revised monograph of the Japanese and Manchou-Korean Muridae. Biogeographica: Transactions of the Biogeo-graphical Society of Japan 4: 1–156. Google Scholar

315.

Tomes, R. F. 1856. Crocidura horsfieldii. Annals and Magazine of Natural History; Zoology, Botany, and Geology, Service 2, 17: 11–28. Google Scholar

316.

Tomida, Y. and Jin, C. 2002. Morphological evolution of the genus Pliopentalagus based on the fossil material from Anhui Province China: a preliminary study. In( Kubodera, T., Higuchi, M. and Miyawaki, R., eds.) Proceedings of The Third and Forth Symposia on Collection Building and Natural History Studies in Asia and The Pacific Rim (National Science Museum Monograph 22), pp 97–107, National Science Museum, Tokyo. Google Scholar

317.

Tomida, Y., Jin, C.-Z, Winkler, A. J. and Oshima, M. 2024. Aztlanolagus revisited and the dynamic evolution of Pliopentalagus (Leporidae, Lagomorpha) in the Holarctic region. Fossil Imprint 80: 229–238. Google Scholar

318.

Tomida, Y. and Otsuka, H. 1993. First discovery of fossil Amami rabbit (Pentalagus furnessi) from Tokunoshima, southwestern Japan. Bulletin of the National Science Museum, Series C (Geology and Paleontology) 19: 73–79. Google Scholar

319.

Tomida, Y. and Takahashi, K. 2023. A new species of Pliopentalagus (Lagomorpha, Mammalia) from the Pliocene Kobiwako Group, central Japan. In( Lee, Y.-N., ed.) Windows into Sauropsid and Synapsid Evolution: Essays in Honor of Prof. Louis L. Jacobs, pp. 332–340, Dinosaur Science Center Press, Seoul. Google Scholar

320.

Toyama, M. 2014. Notes on the names of the Ryukyu Archipelago. Bulletin of the Historiographical Institute 37: 59–68 (in Japanese). Google Scholar

321.

Toyama, M. 2016. Nature and people in Yambaru: bioculture and traditional knowledge. National Parks 747: 15–17 (in Japanese). Google Scholar

322.

Tsuboi, K., Murakami, K., Ishigaki, T., Watanabe, S. and Mizoguchi, Y. 2011. The development of methods to determine the genetic diversity of the Ryukyu wild boar on Iriomote Island. Bulletin of the Faculty of Agriculture, Meiji University 60: 53–59 (in Japanese with English summary). Google Scholar

323.

Tsujino, R., Ishimaru, E. and Yumoto, T. 2010. Distribution patterns of five mammals in the Jomon period, Middle Edo period, and the present, in the Japanese Archipelago. Mammal Study 35: 179–189. Google Scholar

324.

Uchida, S. 1920. Animals on Amami-Oshima Island, Kagoshima Prefecture. Report on Survey of Historic Sites and Natural Monuments (Ministry of the Interior) 23: 41–61 (in Japanese with English summary). Google Scholar

325.

UNESCO. 2021. Amami-Oshima Island, Tokunoshima Island, Northern part of Okinawa Island, and Iriomote Island. Available at  https://whc.unesco.org/en/list/1574 (Accessed 17 August 2024). Google Scholar

326.

van der Geer, A., Lyras, G. and de Vos, J. 2021. Evolution of Island Mammals: Adaptation and Extinction of Placental Mammals on Islands, Second edition. Wiley-Blackwell, Hoboken, 563 pp. Google Scholar

327.

Vasile, R. S., Manning, R. B. and Lemaitre, R. 2005. William Stimpson's journal from the North Pacific Exploring Expedition, 1853–1856. Crustacean Research Special 2005: 1–200. Google Scholar

328.

Veron, G. and Jennigs, A. P. 2017. Javan mongoose or small Indian mongoose–who is where? Mammalian Biology 87: 62–70. Google Scholar

329.

Veron, G., Patou, M.-L., Pothet, G., Simberloff, D. and Jennings, A. P. 2007. Systematic status and biogeography of the Javan and small Indian mongooses (Herpestidae, Carnivora). Zoologica Scripta 36: 1–10. Google Scholar

330.

Watanabe, N. 1970. New discovery of Pleistocene Anthropocene fossils in Okinawa. Anthropological Sciences 23: 207–215 (in Japanese). Google Scholar

331.

Watanabe, N., Arai, K., Otsubo, M., Toda, M., Tominaga, A., Chiyonobu, S., Sato, T., Ikeda, T., Takahashi, A., Ota, H. et al. 2023. Geological history of the land area between Okinawa Jima and Miyako Jima of the Ryukyu Islands, Japan, and its phylogeographical significance for the terrestrial organisms of these and adjacent islands. Progress in Earth and Planetary Science 10: 40. https://doi.org/10.1186/s40645-023-00567-x. Google Scholar

332.

Watanabe, S. and Izawa, M. 2005. Species composition and size structure of frogs preyed by the Iriomote cat Prionailurus bengalensis iriomotensis. Mammal Study 30: 151–155. Google Scholar

333.

Watanabe, S., Nakanishi, N. and Izawa, M. 2003. Habitat and prey resource overlap between the Iriomote cat Prionailurus iriomotensis and introduced feral cat Felis catus based on assessment of scat content and distribution. Mammal Study 28: 47–56. Google Scholar

334.

Watanobe, T., Ishiguro, N., Nakano, M., Takamiya, H., Matsui, A. and Hongo, H. 2002. Prehistoric introduction of domestic pigs onto the Okinawa Islands: ancient mitochondrial DNA evidence. Journal of Molecular Ecology 55: 222–231. Google Scholar

335.

Watanobe, T., Okumura, N., Ishiguro, N., Nakano, M., Matsui, A., Sahara, M. and Komatsu, M. 1999. Genetic relationship and distribution of the Japanese wild boar (Sus scrofa leucomystax) and Ryukyu wild boar (Sus scrofa riukiuanus) analyzed by mitochondrial DNA. Molecular Ecology 8: 1509–1512. Google Scholar

336.

Watari, Y. 2016. Threat of invasive mammals—Why do they have such a strong impact? In( Mizuta, T., ed.) Natural History of the Amami Island Group: Biodiversity of Subtropical Islands, pp. 313–331. Tokai University Press, Hiratsuka (in Japanese). Google Scholar

337.

Watari, Y. 2019. Roadmap and checklist of invasive species management: learning from the mongoose eradication project on Amami-Oshima. Japanese Journal of Ornithology 68: 263–272. Google Scholar

338.

Watari, Y., Nagai, Y., Yamada, F., Sakoda, T., Kuraishi, T., Abe, S. and Satomura, K. 2007. The diet of dogs in the Amami-Oshima Island forests, with special attention to predation on endangered animals. Japanese Journal of Conservation Ecology 12: 28–35 (in Japanese). Google Scholar

339.

Watari, Y., Nishijima, S., Fukasawa, M., Yamada, F., Abe, S. and Miyashita, T. 2013. Evaluating the “recovery-level” of endangered species without prior information before alien invasion. Ecology and Evolution 3: 4711–4721. Google Scholar

340.

Watari, Y., Takatsuki, S. and Miyashita, T. 2008. Effects of exotic mongoose (Herpestes javanicus) on the native fauna of Amami-Oshima Island, southern Japan, estimated by distribution patterns along the historical gradient of mongoose invasion. Biological Invasions 10: 7–17. Google Scholar

341.

Wozencraft, W. C. 1993. Order Carnivora. In( Wilson, D. E. and Reeder, D. M., eds.) Mammal Species of the World. A Taxonomic and Geographic Reference, Second edition, pp. 286–346. Smithsonian Institution Press, Washington. Google Scholar

342.

Wozencraft, W. C. 2005. Order Carnivora. In( Wilson, D. E. and Reeder, D. M., eds.) Mammal Species of the World. A Taxonomic and Geographic Reference, Third edition, pp. 532–628. Johns Hopkins University Press, Baltimore. Google Scholar

343.

Wurster-Hill, D. H., Doi, T., Izawa, M. and Ono, Y. 1987. Banded chromosome study of the Iriomote cat. Journal of Heredity 78: 105–107. Google Scholar

344.

Xu, B. 1721. Chuzan Denshinroku (Geography of Ryukyu), ( Xu, B. and Harada, N. 1982. Chuzan Denshinroku (Geography of Ryukyu). Gensousha, Tokyo, 397 pp.) (in Japanese). Google Scholar

345.

Yabe, T. 1998. Bark-stripping of tankan orange, Citrus tankan, by the roof rat, Rattus rattus, on Amami-Oshima Island, southern Japan. Mammal Study 23: 123–127. Google Scholar

346.

Yamada, E., Anezaki, T. and Hongo, H. 2018. Tooth outline shape analysis of the Ryukyu wild boar (Sus scrofa riukiuanus) and the Japanese wild boar (S. s. leucomystax) by geometric morphometrics. Mammal Study 43: 99–107. Google Scholar

347.

Yamada, F. 2002. Impacts and control of introduced small Indian mongoose on Amami Island, Japan. In( Veitch, C. R. and Clout, M. N., eds.) Turning the Tide: The Eradication of Invasive Species, pp. 389–392. IUCN SSC Invasive Species Specialist Group, IUCN, Grand and Cambridge. Google Scholar

348.

Yamada, F. 2015. Pentalagus furnessi (Stone, 1900). In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 212–213. Shokado, Kyoto. Google Scholar

349.

Yamada, F. 2017. Lagomorphology: Biology of Evasion and Escaping Strategy. University of Tokyo Press, Tokyo, 275 pp. (in Japanese). Google Scholar

350.

Yamada, F. 2021. History of rodent pest control studies in the Zoological Laboratory, Faculty of Agriculture, Kyushu University. Mammalian Science 61: 55–68 (in Japanese with English abstract). Google Scholar

351.

Yamada, F. and Cervantes, F. A. 2005. Pentalagus furnessi. Mammalian Species 782: 1–5. Google Scholar

352.

Yamada, F., Ikeda, T., Ogura, G., Tokida, K., Ishii, N. and Murakami, O. 2009. A report on the international symposium on control strategy of invasive alien mammals 2008-building on success, learning from failures: 100 ways to beat invasive mammals (CSIAM2008). Mammalian Science 49: 177–183 (In Japanese). Google Scholar

353.

Yamada, F., Kawauchi, N., Nakata, K., Abe, S., Kotaka, N., Takashima, A., Murata, C. and Kuroiwa, A. 2010. Rediscovery after thirty years since the last capture of the critically endangered Okinawa spiny rat Tokudaia muenninki in the northern part of Okinawa Island. Mammal Study 35: 243–255. Google Scholar

354.

Yamada, F., Ogura, G. and Abe, S. 2015. Herpestes auropunctatus (Hodgson, 1936). In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 272–274. Shokado, Kyoto. Google Scholar

355.

Yamada, F., Sugimura, K., Abe, S. and Handa, Y. 2000. Present status and conservation of the endangered Amami rabbit Pentalagus furnessi. Tropics 10: 87–92. Google Scholar

356.

Yamada, F., Takaki, M. and Suzuki, H. 2002. Molecular phylogeny of Japanese Leporidae, the Amami rabbit Pentalagus furnessi, the Japanese hare Lepus brachyurus, and the mountain hare Lepus timidus, inferred from mitochondrial DNA sequences. Genes and Genetics Systems 77: 107–116. Google Scholar

357.

Yamamoto, I. and Uchino, Y. 2023. Tsushima leopard cat and Iriomote cat: roadkill and its measurement. In( Yanagawa, H., Tsukada, H. and Sonoda, Y., eds.) Wildlife Roadkill in Japan: From Wildlife Management to Road Ecology, pp. 116–135. University of Tokyo Press, Tokyo (in Japanese). Google Scholar

358.

Yamashina, Y. and Mano, T. 1981. A new species of rail from Okinawa Island. Journal of the Yamashina Institute for Ornithology 13: 147–152 + plates 1–3. Google Scholar

359.

Yamato, N., Kotaka, N., Takashima, A., Nakata, K., Kudaka, N., Kudaka, M. and Kobayashi, S. 2024. Characteristics of nest materials and cavity formations of the Ryukyu long-furred rat (Diplothrix legata, Muridae) on Northern Okinawajima Island, Japan. Mammalian Science 64: 215–225 (in Japanese with English abstract). Google Scholar

360.

Yasuda, M., Seki, S., Watari, Y., Saito, K., Yamada, F. and Kotaka, N. 2017. Historical distribution trends of the critically endangered Okinawa spiny rat Tokudaia muenninki on the Ryukyu Islands. Mammalian Science 57: 227–234 (in Japanese with English abstract). Google Scholar

361.

Yokohata, Y. 2003. The problem of feral goats on Uotsuri Island in the Senkaku Islands and appeals for countermeasures to resolve the problem. Japanese Journal of Conservation Ecology 8: 87–96 (in Japanese with English abstract). Google Scholar

362.

Yokohata, Y. 2015. Mogera uchidai (Abe, Shiraishi & Arai, 1991). In( Ohdachi, S. D., Ishibashi, Y., Iwasa, M. A., Fukui, D. and Saitoh, T., eds.) The Wild Mammals of Japan, Second edition, pp. 42–43. Shoukadoh, Kyoto. Google Scholar

363.

Yokohata, Y., Ikeda, Y., Yokota, M. and Ishizaki, H. 2003. The effects of introduced goats on the ecosystem of Uotsuri-jima, Senkaku Islands, Japan, as assessed by remote-sensing techniques. Biosphere Conservation 5: 39–46. Google Scholar

364.

Yokohata, Y. and Yokota, M. 2000. The problem of introduced goats on Uotsuri-jima in the Senkaku Islands. Wildlife Conservation Japan 5: 1–12 (in Japanese with English summary). Google Scholar

365.

Yokohata, Y., Yokota, M. and Ota, H. 2009. The problem of feral goats and the biota of Uotsuri Island in the Senkaku Islands. IPSHU Research Series 42: 307–326 (in Japanese). Google Scholar

366.

Yoneda, K. 2016. Forest of the Satsunan Shoto. In(Biodiversity Research Group of Kagoshima University, ed.) Biodiversity of Amami Islands, pp. 40–90. Nanpou Shinsha, Kagoshima (in Japanese). Google Scholar

367.

Yoneda, K. 2017. Forests of Amami Islands characterized by strong winds and heavy rainfall: nature and forestry there. National Parks 752: 9–11 (in Japanese). Google Scholar

368.

Yoshikawa, S., Mimura, M., Watanabe, S., Lin, L.-K. and Ota, H. and Mizoguchi, Y. 2016. Historical relationships among wild boar populations of the Ryukyu Archipelago and other Eurasian regions, as inferred from mitochondrial cytochrome b gene sequences. Zoological Science 33: 520–526. Google Scholar

369.

Yoshiyuki, M. 1971. A new bat of the Leuconoe group in the genus Myotis from Honshu, Japan. Bulletin of the National Museum of Nature and Science Series A Zoology 14: 305–310. Google Scholar

370.

Yoshiyuki, M. 1989. A Systematic Study of the Japanese Chiroptera. National Science Museum, Tokyo, 242 pp. Google Scholar
Fumio Yamada and Masako Izawa "A Historical Review of Studies and Conservation Practices for Terrestrial Mammals in the Central and Southern Ryukyu Archipelago in Japan," Mammal Study 50(2), 109-141, (2 April 2025). https://doi.org/10.3106/ms2024-0044
Received: 19 August 2024; Accepted: 11 February 2025; Published: 2 April 2025
KEYWORDS
biodiversity hotspot
Endemism
island biology
Natural World Heritage
subtropical islands
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