Hawaiian nectarivorous forest birds play a vital ecological role as pollinators in Hawaiian ecosystems. However, little is known about what nectar resources are utilized by Hawai‘i's nectarivorous birds, how seasonality influences nectar availability, and how nectar preference differs by bird species. We sampled pollen from the heads of ‘i‘iwi (Drepanis coccinea), ‘apapane (Himatione sanguinea), Hawai‘i ‘amakihi (Chlorodrepanis virens), and the non-native Japanese white-eye (Zosterops japonicas) captured at Hakalau Forest National Wildlife Refuge on Hawai‘i Island. ‘Ōhi‘a (Metrosideros polymorpha) was the most prevalent pollen species, observed throughout the sampling period while other pollen species were more seasonal in occurrence. Consistent with the peak flowering phenology of the plant species, pollen from koa (Acacia koa), māmane (Sophora chrysophylla), and gorse (Ulex europaeus) plant speciesweremore commonly sampled frombirds in the winter months, while ‘ōhelo (Vaccinium reticulatum), ‘ākala (Rubus hawaiensis), and blackberry (Rubus argutus)were more prevalent during the spring months.We also found an association between bird species and pollen resources, with ‘i‘iwi and Hawai‘i ‘amakihi having a higher diversity of pollen than ‘apapane and Japanese white-eye, which primarily had just ‘ōhi‘a. These results demonstrate that ‘ōhi‘a is likely the most important nectar resource for Hawai‘i's nectar feeding birds, but seasonally abundant nectar may be important for some species.

Invasive rats (Rattus rattus, R. norvegicus, R. exulans) are recognized as a major threat to native island ecosystems and biodiversity. On many islands, two or three invasive rat species co-occur, often sharing the same habitat; however few studies have focused on the effects of coexisting invasive rat species on native biodiversity. We investigated rat population ecology and diet in a New-Caledonian rainforest where black (Rattus rattus) and Pacific rats (R. exulans) coexist. Black rats dominated Pacific rats in relative abundance with a proportion varying between 80.9 and 88.9%. A total of 374 black rats and 87 Pacific rats were sampled for diet assessment through stomach and caecum analysis. Rat diet was mainly composed of plants, invertebrates and to a lesser extent Squamata, with black rats being more frugivorous and Pacific rats being more omnivorous. Ten of 15 endemic skink and gecko species were consumed, nine species by black rats and six species by Pacific rats. Thus, the presence of both rat species may strengthen the overall predation rate on each native prey species, and/or broaden the total number of native prey species impacted in the New-Caledonian rainforest. These results highlight the importance of preventing new rat species introduction on islands to avoid the strengthening and/or the broadening of negative effects on native biodiversity, and the importance of following the proportion of each rat species during rat control operations. Research to assess the threats generated by various assortments of rodent species on native biodiversity could improve priority setting in conservation actions.

Two small Indian mongooses (Herpestes auropunctatus) were livecaptured in 2012 at separate locations on the Hawaiian Island ofKaua‘i, which was previously considered to be free of this invasive species.Genotypes from these two individuals were compared to genotypes of H. auropunctatus from the islands of Hawai‘i (n = 39),O‘ahu (n = 91),Maui (n = 39), and Moloka‘i (n = 19) to determine the island of origin of theKaua‘i individuals. Genotypes were generated fromeach individual using five microsatellite loci. Genetic clustering was estimated by Bayesian inference of spatial clustering of individuals and clustering of groups of individuals. Both analyses separated the samples into three distinct genetic clusters (K = 3).Kaua‘i individuals consistently formed a single cluster with individuals from O‘ahu, whereas Hawai‘i and Maui formed a second cluster, and Moloka‘i was the third cluster.Thus, we conclude that the origin of two H. auropunctatus captured on Kaua‘i wasO‘ahu. All three genetic clusters showed evidence of transportation of mongooses between islands, indicating that sampled islands in the archipelago are capable of acting as both donors and receivers of mongooses.

The Japanese Wood Pigeon, Columba janthina, is an endemic species that lives only on the East Asia-Pacific islands. The population of this species on Ulleung Island, South Korea varies in size with season, but the cause for this was unknown. We hypothesized that Japanese Wood Pigeons migrate seasonally between breeding and non-breeding sites and accordingly studied their movement from 28 June 2017 to 20 April 2018 using GPS transmitters. We report the first evidence of seasonal migration of Japanese Wood Pigeons to nonbreeding sites (Okinoshima and Nishinoshima Islands in Japan), 278 km from the breeding site (Ulleung Island). This migration route was on the East Asian-Australasian flyway and constitutes the longest flight ever recorded for Japanese Wood Pigeons. Our finding has significant implications for understanding previously disputed aspects of the ecology of Japanese Wood Pigeons, including geographical isolation, hybridization, population retention, and patterns of movement.

Efficient in situ and ex situ conservation strategies are urgently needed in biodiversity hotspots, where high concentrations of endemic plant species are undergoing exceptional loss of habitat. In particular, determining seed desiccation sensitivity is a key prerequisite to design storage methods useful for ex situ programs. In this study, we explored seed desiccation sensitivity and its link with phenological and morphological traits as well as with the environmental variables for 45 New Caledonian plant species. Desiccation sensitivity was quantified through RH50, that is, the relative humidity at which 50% of initial viable seeds died. RH50 was found to be positively associated with the initial seed water content, seed mass, precipitation seasonality, precipitation of the warmest quarter, and presence in rainforest habitats. In contrast, the ability of species to endure desiccation increased in drier habitats such as dry forest. We also found that desiccation sensitivity was consistent at the genus level. These new data provide the basis to establish conservation plans for a large array of plant species in New Caledonia. Moreover, this study may help us to better understand the underlying mechanisms of desiccation sensitivity and to predict desiccation sensitivity of other taxa within the New Caledonian flora on the basis of taxonomy, functional traits and environmental features.

Studies on secondary production can lead to a better understanding of the functions of the macrobenthic ecosystem. To determine the secondary productionand production-to-biomass ratio(P/B) of the macrobenthic community in the northern East China Sea, we conducted annual investigations in the northern East China Sea from 2012 to 2016. In this study, the secondary production and P/B values of the macrobenthic community in the northern East China Sea, China, were described and analysed using PCA and Spearman rank correlation analysis. A total of 61 species were collected and identified, and the results showed that Polychaeta was the most speciose group. The polychaete Sternaspis scutata and holothurian Acaudina molpadioides were found to be the most important contributors to the total abundance and total biomass across all sampling areas and years. The Spearman rank correlation analysis indicated that community abundance was positively correlated with depth but negatively correlated with dissolved oxygen (DO) and suspended solids (SS). The P/B was much lower than that found in previous reports from this area, mainly due to the collection of large individuals of A. molpadioides from Sanmen Bay. The low P/B value also indicated that more effort and time are needed to rehabilitate the benthic marine ecosystem in this area.

Killer whales (Orcinus orca) are widely distributed in all ocean basins, however, their occurrence, distribution, and ecology in the southeast Pacific, including Peru, is poorly defined. This study aims to describe the occurrence of killer whales in Peruvian waters, with additional description of predatory behaviors. Between 2003 and 2018 there were 29 reports of killer whales in Peruvian waters in which at least 110 individuals were observed, with pod sizes ranging between 1 and 15 individuals. Most sightings occurred in waters within the continental shelf or in close proximity to the shelf break. During eight of the sightings, killer whales displayed predatory behavior towards other marine mammals, including cetaceans (Megaptera novaeangliae and Balaenoptera musculus) and pinnipeds (Otaria flavescens and Arctocephalus australis). In addition, we present the first photo-analysis of the incidence of killer whale tooth rake marks on humpback whale flukes off northern Peru. Between 2009 and 2017, 897 unique individual humpback whales were photo-identified off northern Peru, of which 19.6% (n = 172) displayed rake marks in their flukes, suggesting that humpback whales in the southeast Pacific are exposed to the attack of killer whales. Our findings suggest that the occurrence of killer whales in Peruvian waters are more common than previously documented and that killer whales are preying marine mammals in this region. Further understanding killer whale distribution, foraging habitats, and movement patterns within Peruvian waters will be essential in promoting their conservation.

From October 2011 to May 2012, we conducted the first marine mammal surveys of Okinawan waters, using line-transect vessel surveys and passive acoustic monitoring (PAM). We obtained 913 km of visual survey effort, and 1,039 cumulative hours of PAM data from around the island. Only a single on-effort sighting was made (of two common bottlenose dolphins [Tursiops truncatus]) during visual surveys, and acoustic detection rates were generally low, with the exception of humpback whale (Megaptera novaeangliae) observations during their winter/spring breeding season. The apparent low density of at least some marine mammals observed in Okinawan waters may be due to the depletion of coastal populations. We believe this could result from many decades of heavy and largely-uncontrolled hunting of small cetaceans in waters around the island.

The taxonomy of the East Pacific land crab Johngarthia planata (Stimpson, 1860) is reviewed and a neotype designated to stabilize the taxonomy of this species. The population of J. planata is found to be restricted to inshore islands and the continental mainland coast of the tropical and subtropical Pacific coast of America. A new species, Johngarthia oceanica sp. nov., is described for populations that occur on the oceanic Clipperton and Socorro islands. Johngarthia oceanica sp. nov., canbeseparatedfromJ. planatabythebroad, subrectangularmesial lobeof the infraorbitalmargin (narrow, subtriangular in J. planata) and a dorsal carapace that is dark yellow to brightly orange with or without black areas of different extension (homogeneously red to maroon in J. planata). The distribution of J. planata is modeled using MaxEnt and the biogeography of East Pacific species of Johngarthia is discussed. The conservation status of the Clipperton population of J. oceanica sp. nov. deserves special attention because this population may be threatened by introduced rats.