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Intraspecific resource partitioning may play a critical role in how predators optimize prey selection. The Black-footed Ferret (Mustela nigripes; henceforth, ferret) is a highly specialized predator of prairie dogs (Cynomys spp.; henceforth, PDs). Adult ferrets are sexually dimorphic and PDs are of similar size making them a difficult prey item. PD young are born 6 to 8 weeks prior to births of ferrets, producing a crop of smaller prey items during a period when energetic needs of female ferrets are highest. We asked whether relatively small female ferrets select small PDs as prey. We examined survival rates from early to late summer for large and small black-tailed PDs (Cynomys ludovicianus) in Montana and South Dakota as a function of their distance to adult male and female ferrets using capture–mark–recapture of PDs and simultaneous summer monitoring of ferret locations. Survival of small PDs (<600 g) was low when a female ferret was nearby, but distance to nearest female ferret did not affect survival of large PDs. Distance to the nearest male ferret did not influence survival regardless of PD size. Reduced competition from males for a critical food resource needed by females rearing young would benefit fitness of both sexes. If female ferrets depend on young PDs during their reproductive period, existing habitat models may substantially overestimate ferret carrying capacity.
The Andes are known to be one of the most species-rich regions on Earth, with their origination promoting formation of new habitats and acting as climatic barriers. This orogenic event was structured latitudinally with 3 major segments having different formation times and with different environmental and historical conditions. The Andean region has been historically important in the evolutionary history of small mammals and is considered the region of Earth with the highest values of rodent species richness and turnover. Therefore, the region provides an excellent opportunity to evaluate mechanisms involved in structuring rodent assemblages and beta diversity patterns. Here, we assessed spatial patterns of rodent beta diversity along the Andes Mountains, with specific goals of examining patterns of turnover and nestedness as 2 recognized processes that drive species composition. We explored the role of spatial, climate, and historical factors on beta diversity patterns using geographic range maps for 432 rodent species to construct a species presence–absence matrix. We used piecewise regressions to identify latitudinal breakpoints in turnover and nestedness, and conducted multiple regressions and variation-partitioning approaches to assess the contribution of each set of postulated drivers in shaping beta diversity patterns. Beta diversity decreases from north to south. The highest turnover was located at the Northern Andes (5°N and 10°S) and western-central Andes (20°S and 35°S). Nestedness was higher below 40°S and in some areas of the western-central Andes between 15° and 20°S. Turnover and nestedness registered breakpoints coincident with the Central and Southern Andes limit. Turnover explained most of the beta diversity for all segments, although within the Southern Andes there was also some contribution of nestedness. In all segments, beta diversity was mainly explained by spatial factors with minor contributions from spatially structured climate (Northern Andes), interaction of all factors (Central Andes), and the interaction between current climate and history (Southern Andes).
Los Andes son reconocidos como una de las regiones más ricas en especies de la tierra, ya que su levantamiento favoreció la formación de nuevos hábitats y actuó como barrera climática. Este evento orogénico se estructuró latitudinalmente en 3 segmentos, cada uno con tiempos de formación características ambientales y condiciones históricas diferentes. La región Andina ha sido un importante escenario en la historia evolutiva de los pequeños mamíferos y es considerada la región con mayor riqueza y recambio de especies. Por lo tanto, es un excelente escenario para evaluar los mecanismos que estructuran los patrones de diversidad beta del ensamble de roedores. Aquí evaluamos el patrón espacial de la diversidad beta de roedores a lo largo de la Cordillera de los Andes, descomponiéndolo en recambio y anidamiento, con el fin de comprender los procesos subyacentes que determinan la composición de especies. Exploramos el papel de los factores espaciales, climáticos e históricos sobre los patrones de diversidad beta utilizando mapas de distribución geográfica para 432 especies de roedores obtenidos de la Base de Datos de Diversidad de Mamíferos y construimos una matriz de presencia-ausencia de especies (PAM). Utilizamos regresiones por tramos (picewise) para identificar los puntos de quiebre latitudinales en recambio y anidamiento, y realizamos regresiones múltiples y partición de la varianza para evaluar la contribución de cada conjunto de factores en la conformación de los patrones de diversidad beta. La diversidad beta disminuye de Norte a Sur, con un mayor recambio en los Andes del Norte (5°N y 10°S) y en la zona central oeste (20°S y 35°S). El anidamiento fue más alto por debajo de los 40°S y en algunas áreas del centro oeste entre los 15° y 20°S. Tanto el recambio como el anidamiento registraron puntos de quiebre coincidentes con el límite entre el segmento Central y el Sur. El recambio explica la mayor parte de la diversidad beta para todos los segmentos, aunque el anidamiento contribuye también a la diversidad beta de los Andes del Sur. En todos los segmentos andinos la diversidad beta se explicó principalmente por factores espaciales con una menor contribución del clima actual (NA), por la interacción de todos los factores (CA) y la interacción entre el clima histórico con el actual (SA).
With up to 137 species worldwide, Myotis,— a genus of small, insectivorous bats are an example for understanding biogeographic and evolutionary processes such as intercontinental colonization, diversification, speciation, and convergent adaptive evolution. Species limits and associated distributions, however, remain poorly delineated across significant portions of this diverse group and encompassing a vast geographic range. Here, we explore how diversity is partitioned across this radiation with a focus on Neotropical species of Myotis, using a barcoding approach (706 bp of the mitochondrial DNA gene cytochrome-b) that includes 544 individual sequences (116 newly generated sequences and 428 sequences from GenBank, including outgroups). Single-locus molecular barcoding is useful for identifying cryptic diversity and establishing hypotheses that can guide investigations of species boundaries and phylogenetic relationships, an especially important initial step in assessing poorly characterized, diverse clades. The global phylogeny produced from these data is consistent with the hypothesized monophyly of the New World clade and places the evolutionary relationships of Neotropical species of Myotis within the context of the Palearctic and Nearctic clades. We then explore species boundaries for 25 of the 36 nominal species of Neotropical Myotis, using 3 alternative species delimitation approaches (1 distance-based ABGD [Automatic Barcode Gap Discovery]; and 2 coalescent-based mPTP [multi-rate Poisson Tree Processes], GMYC [Generalized Mixed Yule Coalescent] model). The mPTP (n = 29 species) and ABGD (n = 26) approaches inferred different numbers of species than that recognized by current Neotropical Myotis taxonomy, whereas GMYC (n = 25) inferred the same number of species. In addition to the original 36 Neotropical nominal species currently recognized, we suggest that taxonomic revisions are needed to assess whether M. oxyotus gardneri and M. nigricans osculatii should be elevated to the species level and whether M. dinellii is distinct from M. levis. With the 7 potentially cryptic species identified herein that require further study, the number of Neotropical Myotis may approach 45 species. Taken together, our results suggest that rather than a classic example of a temperate radiation, there may be more species of Myotis in the Neotropics than Nearctic, Afrotropic, Indomalayan, and Oceanian Realms, with only the Palearctic region showing higher species richness.
Con hasta 137 especies en todo el mundo, Myotis, un género de pequeños murciélagos insectívoros, es un ejemplo para comprender los procesos biogeográficos y evolutivos como la colonización intercontinental, la diversificación, la especiación y la evolución adaptativa convergente. La delimitación de especies y sus distribuciones asociadas, sin embargo, son poco conocidas en este diverso grupo, incluyendo gran parte de su rango de distribución. En este estudio exploramos la diversidad genética en la radiación mundial de Myotis con especial interés en las especies de Myotis neotropicales utilizando una aproximación de código de barras (706 pares de bases del gen citocromo-b), el cual incluye 544 secuencias individuales (116 secuencias han sido generadas en este estudio, mientras que 428 secuencias fueron obtenidas de GenBank, incluyendo grupos externos). Estudios de código de barras empleando un solo gen constituyen un paso inicial para la identificación de diversidad críptica y establecer hipótesis preliminares que puedan guiar investigaciones relacionadas a la delimitación de especies límite de especies y sus relaciones filogenéticas, de manera especial en clados diversos que han sido poco caracterizados. Esta filogenia mundial es consistente con previas hipótesis filogenéticas, las cuales sugieren la monofilia del clado de Myotis del Nuevo Mundo, así como establece las relaciones evolutivas de las especies Neotropicales en relación con las especies Neárticas y Paleárticas. Además, se exploró los límites de especies del clado neotropical (25 de 36 especies nominales) utilizando un método de delimitación de especies basado en distancias genéticas (ABGD [Automatic Barcode Gap Discovery]) y dos métodos basados en coalescencia (mPTP [multi-rate Poisson Tree Processes], GMYC [Generalized Mixed Yule Coalescent] model). Los métodos de delimitación mPTP (n = 29 especies) y ABGD (n = 26 especies) infirieron un número diferente en comparación con el número de especies reconocidas por taxonomía actual de Myotis neotropicales, sin embargo, GMYC (n = 25) infirió el mismo número de especies. A parte de las 36 especies nominales actualmente reconocidas, sugerimos nuevas revisiones taxonómicas para confirmar el rango de especie de M. oxyotus gardneri y M. nigricans osculatii, y si M. dinellii es una especie diferente de M. levis. Con siete especies crípticas identificadas en este estudio, el número de especies neotropicales podría aproximarse a las 45 especies. Nuestros resultados sugieren que existen más especies de Myotis en el Neotrópico que en las regiones Neárticas, Afrotropicales, Indomalaya y Oceanía, con la excepción de la región Paleártica.
Using sequences from 2,615 ultraconserved element (UCE) loci and multiple methodologies we inferred phylogenies for the largest genetic data set of New World bats in the genus Myotis to date. The resulting phylogenetic trees were populated with short branch lengths and widespread conflict, hallmarks consistent with rapid adaptive radiations. The degree of conflict observed in Myotis has likely contributed to difficulties disentangling deeper evolutionary relationships. Unlike earlier phylogenies based on 1 to 2 gene sequences, this UCE data set places M. brandtii outside the New World clades. Introgression testing of a small subset of our samples revealed evidence of historical but not contemporary gene flow, suggesting that hybridization occurs less frequently in the Neotropics than the Nearctic. We identified several instances of cryptic lineages within described species as well as several instances of potential taxonomic oversplitting. Evidence from Central and South American localities suggests that diversity in those regions is not fully characterized. In light of the accumulated evidence of the evolutionary complexity in Myotis and our survey of the taxonomic implications from our phylogenies, it is apparent that the definition of species and regime of species delimitation need to be reevaluated for Myotis. This will require substantial collaboration and sample sharing between geneticists and taxonomists to build a system that is both robust and applicable in a genus as diverse as Myotis.
Utilizando secuencias de 2615 loci de elementos ultraconservados (UCE, por sus siglas en inglés) y múltiples metodologías, inferimos filogenias para el conjunto de datos genéticos más grande hasta la fecha de Myotis del Nuevo Mundo. Los árboles filogenéticos recuperados presentaron ramas de longitud corta y conflictos generalizados, características consistentes con rápidas radiaciones adaptativas. El grado de conflicto observado en Myotis probablemente ha contribuido a las dificultades para desentrañar relaciones evolutivas más profundas. A diferencia de filogenias anteriores basadas en secuencias de 1-2 genes, este conjunto de datos de UCE sitúa a M. brandtii fuera de los clados del Nuevo Mundo. Las pruebas de introgresión en un pequeño subconjunto de nuestras revelaron evidencia de flujo génico histórico, pero no contemporáneo, lo que sugiere que la hibridación ocurre con menos frecuencia en el Neotrópico que en el Neártico. Identificamos varios casos de linajes crípticos dentro de especies descritas, y varios casos potenciales de separación taxonómica excesiva. La evidencia de localidades en Centro y Sudamérica sugiere que la diversidad en esas regiones no está completamente caracterizada. Teniendo en cuenta el cúmulo de información sobre la complejidad evolutiva en Myotis y la exploración de las implicaciones taxonómicas en nuestras filogenias es evidente la necesidad de la definición y el rigor de la delimitación de especies de Myotis deban ser reevaluados. Esto requerirá una colaboración sustancial y el intercambio de muestras entre genetistas y taxónomos para construir un sistema que sea robusto y aplicable en un género tan diverso como Myotis.
Temperate bats exhibit seasonal and sex differences in resource selection and activity patterns that are influenced by ambient conditions. During fall, individuals face energetic trade-offs as they make choices relating to migration, mating, and hibernation that may diverge for populations throughout their range. However, research has largely focused on the summer maternity and winter hibernation seasons, whereas the prehibernation period remains comparatively understudied. Northern Myotis (Myotis septentrionalis) have experienced precipitous population declines from white-nose syndrome (WNS), leading to their protected status in the United States and Canada. Therefore, understanding their ecology throughout the year is paramount to inform conservation. We compared seasonal roosts and documented fall behaviors between study sites and sexes on 3 islands: Long Island (New York), Martha's Vineyard, and Nantucket Island (Massachusetts). Between 2017 and 2020, we radio-tracked 54 individuals to analyze activity patterns and characterize fall roosts to compare with previously known summer roosts. Summer tree roosts were of smaller diameter, later stages of decay, and lower canopy closure than those used in fall. Both sexes selected trees of similar diameter and decay stage during fall. Anthropogenic roost use was documented in both seasons but use of anthropogenic structures was greater during fall and increased as the season progressed. Bats made short inter-roost movements with males traveling greater distances than females on average. Activity occurred until late November, with males exhibiting a longer active period than females. We tracked 23% of tagged bats to local hibernacula in subterranean anthropogenic structures, the majority of which were crawlspaces underneath houses. Use of anthropogenic structures for roosts and hibernacula may facilitate survival of this species in coastal regions despite the presence of WNS infections. Timing of restrictions on forest management activities for bat conservation may be mismatched based on prehibernation activity observed in these coastal populations, and the conservation of habitat surrounding anthropogenic roosts or hibernacula may be warranted if the structures themselves cannot be protected.
Passive integrated transponders (PIT tags) can aid in the collection of important demographic data for species for which other methods, such as GPS technology, are not suitable. PIT tags can be particularly suitable to monitor small and cryptic species like bats and permit inference on their behavioral ecology. Literature for several species of bats states that females change their nightly activity patterns—going out and in of the roost only once per night during gestation compared to several times during lactation. Hence, we tested whether PIT tag detection patterns could be used to infer reproductive status and parturition date of female bats. From 2017 to 2021, we recorded detections of PIT-tagged little brown (Myotis lucifugus) and northern long-eared bats (M. septentrionalis) at the entrance of 2 maternity roosts in Québec and Newfoundland, Canada. We also used the maternity roost in Québec as a case study to further evaluate the potential of this method to link behavior and demography and investigated factors affecting parturition date. We were able to infer reproductive status for 63% to 97% of tagged individuals detected during both the gestation and the lactation periods, and parturition date for 61% to 95% of reproductive individuals, depending on the year and roost. Early spring arrival at the roost and warm spring mean temperature at night were associated with earlier parturition dates. Herein, we highlight that PIT tag systems may be useful to detect changes in activity patterns of female bats and infer individual reproductive parameters, which is on the long-term less stressful for bats and easier for researchers. We demonstrate that this approach is useful to investigate intrinsic and extrinsic factors of reproductive parameters, improving our understanding of bat population dynamics resulting in more informed population management decisions.
Los transpondedores pasivos integrados (PIT tags) pueden ayudar en la recolecta de datos demográficos importantes de especies para las que otros métodos como la tecnología GPS no son adecuados. Los PIT tags pueden ser adecuados especialmente para el seguimiento de especies pequeñas y crípticas como los murciélagos y permiten inferir sobre su ecología comportamental. Según la literatura, las hembras de varias especies de murciélagos cambian sus patrones de actividad nocturna de una salida y regreso al refugio durante la gestación, a varias salidas y regresos durante la lactancia. Por lo tanto, probamos si los patrones de detección de PIT tags pueden utilizarse para inferir el estado reproductivo de los murciélagos hembra y las fechas de parto. Entre 2017 y 2021, registramos detecciones del murciélago pardo pequeño (Myotis lucifugus) y del murciélago de orejas largas del norte (Myotis septentrionalis) marcados con PIT tags, en la entrada de dos refugios de maternidad en Quebec y Terranova, Canadá. También utilizamos el refugio de maternidad de Quebec como estudio de caso y evaluar, con más detalle, el potencial de este método para vincular comportamiento y demografía, e investigamos los factores que afectan la fecha de parto. Inferimos el estado reproductivo de entre el 63 y el 94% de los individuos marcados detectados durante los períodos de gestación y lactancia, y la fecha de parto de entre el 61 y el 95% de los individuos reproductivos, dependiendo del año y del refugio. La llegada temprana a los refugios y la temperatura cálida promedio durante la noche en primavera se asociaron con fechas de parto más tempranas. Por lo tanto, resaltamos que los sistemas de marcaje PIT tag pueden ser útiles para detectar cambios en los patrones de actividad de los murciélagos hembra e inferir parámetros reproductivos individuales, lo cual es, a largo plazo, menos estresante para los murciélagos y más fácil para los investigadores. Demostramos que este enfoque es útil para investigar los factores intrínsecos y extrínsecos de los parámetros reproductivos, mejora nuestra comprensión de la dinámica de las poblaciones de murciélagos y se espera que pueda emplearse en la toma de decisiones de manejo de las poblaciones.
We have successfully measured the sleep electroencephalogram (EEG) of 12 family cats during an afternoon nap using a completely noninvasive methodology originally developed and validated for family dogs. Extracting both macrostructural and spectral sleep variables from the acquired data, we: (1) provided a descriptive analysis of sleep structure in cats and the power spectral density (PSD) distribution considering 3 sleep stages—drowsiness, non-rapid eye movement (NREM), and rapid eye movement (REM) sleep; and (2) compared the results to those obtained in family dogs measured under the same conditions and using the same methodology. Importantly, our description of sleep structure and PSD distribution in cats proved to be comparable to those of earlier invasive studies, highlighting that appropriate noninvasive methodologies may provide a viable alternative to those that are invasive in some cases. While no macrostructural differences were found between the sleep of cats and dogs, and the characteristic PSDs were mostly similar across sleep stages within the 2 species, the high-frequency resolution comparison of PSD distributions revealed differences between the 2 species in all sleep stages (concerning the delta, theta, alpha, sigma, and beta bands in drowsiness and NREM sleep; and the delta, alpha, and sigma bands in REM sleep). Potential factors underlying these differences are discussed, including differences in circadian rhythms, sleep homeostatic regulation, experienced stress, or even differential attitudes toward owners—highlighting important links between sleep characteristics and often more complex neural and behavioral features.
Sunčica Stipoljev, Elena Buzan, Laura Iacolina, Toni Safner, Andrea Rezić, Ana Galov, Krešimir Križanović, Hüseyin Ambarlı, MariaCruz Arnal, Elmar Babaev, Ferdinand Bego, Attila Farkas, Dragan Gačić, Peter Lazar, Vladimir Maletić, Georgi Markov, Dragana Milošević, Haritakis Papaioannou, Massimo Scandura, Nikica Šprem
Major histocompatibility complex (MHC) genes are commonly used markers for monitoring adaptive genetic and evolutionary potential of species. In this study, we investigated genetic variation of the MHC class II DRB locus in the chamois genus Rupicapra by using next-generation sequencing. Sequencing of 102 samples led to the identification of 25 alleles, 11 of which are novel. The high ratio of the relative rates of nonsynonymous to synonymous mutations (dN/dS) suggests a signal of positive selection on this locus. We analyzed patterns of genetic variation within and among 2 subspecies of Northern Chamois and compared them to previously published studies using neutral markers to provide a basis for assessing the effects of demographic processes. Our analyses have shown that alleles are likely to be maintained by balancing selection in different populations with similar frequencies and that this mechanism also works in small, isolated populations that are strongly affected by genetic drift.
Ground squirrels act as important members of grassland ecosystems by serving as both ecosystem engineers and as a prey base for carnivores. There is mounting evidence that climate change is driving ground squirrel population declines. We resurveyed 54 historical localities throughout the Wyoming Basin and western Colorado where Wyoming Ground Squirrel (Urocitellus elegans) specimens were collected to investigate if climate change was driving extirpations at these historically occupied sites. We detected extirpations at 12 sites and used binomial generalized linear models in an information-theoretic framework to investigate if climate change was associated with these extirpations. Additionally, we investigated if land cover change was associated with persistence and if land cover ameliorated or exacerbated the effects of climate change. We found that changes in climate, especially increasingly dry summer air and increasing mean summer temperatures, were associated with a reduced probability that U. elegans persisted at a historically occupied site. In addition, we found that current forest cover at a site and increasing rangeland cover at the regional level were associated with reduced probability that U. elegans persisted, although these associations were weaker than the climate associations. The effects of climate change and land cover change did not interact. Our findings build on mounting evidence that montane-associated ground squirrels throughout the Western United States are negatively impacted by climate change. The reduction in ground squirrel abundance or their extirpation due to climate change could lead to changes in ecosystem structure or reductions in trophic complexity.
Globally, animals that are range-restricted are frequently becoming species of conservation concern, in part due to competitive exclusion by phylogenetically and ecologically similar species that are more tolerant of human disturbance. However, climate and land use changes to natural landscapes can create pockets of refugia for range-restricted species. Western gray squirrels (Sciurus griseus) are native to the west coast of North America, principally California and western Oregon. Over the past several decades, Western Gray Squirrel populations have declined in human-dominated areas, with increased competition from introduced congeneric species native to eastern North America cited as a primary driver. Despite declines in their established range west of the Pacific Crest in western North America, western gray squirrels are extending their range into the Great Basin, where they were not historically found. Using a network of remote camera traps deployed across the Sierra Nevada–Great Basin ecotone in northwestern Nevada, we detected western gray squirrels across 16 of 100 camera-trapping sites. The majority of detections were located in piñon–juniper woodland, a land cover type not previously occupied by this species. Occupancy modeling revealed that western gray squirrels were equally likely to occur in piñon–juniper woodland compared to mature pine forest that they occupy elsewhere in their range. A species distribution model parameterized with historical gray squirrel observations (pre-1950), indicated increased climatic suitability for the species on the eastern side of the Sierra Nevada in recent decades, which may have facilitated this range expansion. Our findings reveal the potential for species declining in their historical range to colonize novel habitats that become increasingly suitable as a result of human-driven changes to ecosystems.
Mammals that cope with harsh environmental conditions by hibernating show seasonal variation in body mass, as fat reserves are accumulated during summer and depleted during winter. In hibernating species, pre-hibernation mass is often considered a key phenotypic trait that can influence future survival and reproductive success—yet we know little about how variation in environmental conditions and seasonality affect pre-hibernation mass. We used 30 years of demographic data from a high-elevation population of golden-mantled ground squirrels (Callospermophilus lateralis) to identify life history and environmental variables that influenced pre-hibernation mass in females. Additionally, we determined if pre-hibernation mass influenced overwinter survival or subsequent reproduction. Growth curves revealed female-biased size dimorphism in body mass; adult mass was not attained until age 2 years, so we considered 3 age classes of females: juveniles, yearlings, and adults (≥2 years). We found that earlier snow melt during spring is associated with higher subsequent pre-hibernation body mass for yearlings and adults, and that juveniles emerging earlier from their natal burrows had higher pre-hibernation masses than later-emerging juveniles. Estimates of food quantity or quality did not affect pre-hibernation mass for any age class, nor was there an effect of reproductive status. Juvenile females with greater pre-hibernation mass were more likely to survive overwinter and reproduce as yearlings, but we found no such effect for yearlings or adult females. We did not find an effect of snow depth or winter duration on either survival or reproduction. Our results indicate that time appears to be the key variable for golden-mantled ground squirrels to acquire sufficient body mass to survive and reproduce, but the effects vary by age class.
Female advertisement of reproductive state and receptivity has the potential to play a large role in the mating systems of many taxa, but investigations of this phenomenon are underrepresented in the literature. North American red squirrels (Tamiasciurus hudsonicus) are highly territorial and engage in scramble competition mating, with males converging from spatially disparate territories to engage in mating chases. Given the narrow estrus window exhibited in this species, the ubiquitous use of vocalizations to advertise territory ownership, and the high synchronicity of males arriving from distant territories, we hypothesized that female vocalizations contain cues relating to their estrous state. To test this hypothesis, we examined the spectral and temporal properties of female territorial rattle vocalizations collected from females of known reproductive condition over 3 years. While we found no distinct changes associated with estrus specifically, we did identify significant changes in the spectral characteristics of rattles relating to both female body mass and reproductive state relative to parturition. To the best of our knowledge, this is the first evidence of changes in vocal characteristics associated with late pregnancy in a nonhuman mammal.
We describe 3 new species of shrews (Eulipotyphla, Soricidae, Crocidura) from West Sumatra, Indonesia. Two of these taxa were found above 1,800 m on Mt. Singgalang. The third taxon was found above 1,660 m on Mt. Talamau, 65 km northwest of Mt. Singgalang. We also resurrect Crocidura aequicauda based on 2 specimens from Mts. Tujuh and Kerinci, which lie near the border between West Sumatra and Jambi provinces. Several methodological approaches support our findings: linear cranial morphometrics, landmark-based 2D geometric morphometrics, and molecular phylogenetics using both mtDNA and 6 nuclear exons. A multilocus species-tree analysis places the 3 new species and C. aequicauda in a clade with the Javan endemics C. monticola and C. umbra. Although the 2 taxa from Mt. Singgalang are recovered as sister species, 1 is nearly twice the size of the other, and they are divergent in several other morphological characters, such as tail length, cranium size, and pelage color and texture. Recently diverged yet morphologically disparate sister taxa living syntopically in an isolated habitat “island,” like the montane forests of Mt. Singgalang, is unusual in mammals but documented in other Crocidura on neighboring Java and Borneo; these 2 new taxa represent the first known case of this phenomenon on Sumatra. Our results bring the number of Sumatran Crocidura to 10, 9 of which are endemic to the island. All 3 of the new species appear to be endemic to a single mountain and were not detected in similar surveys of nearby mountains. If this local endemism pattern is common, it would indicate that Sumatra's mammal diversity may be severely underestimated, largely due to the paucity of small-mammal surveys and museum specimens.
Kami mendeskripsikan tiga species baru cecurut (Eulipotyphla, Soricidae, Crocidura) dari Sumatera Barat, Indonesia. Dua dari tiga taksa ini ditemukan pada ketinggian di atas 1,800 meter di Gunung Singgalang. Takson ketiga ditemukan di atas 1,660 m di Gunung Talamau, 65 km di sebelah barat laut Gunung Singgalang. Kami juga membangkitkan kembali Crocidura aequicauda berdasarkan dua specimen dari Gunung Tujuh dan Gunung Kerinci, yang terletak didekat perbatasan antara provinsi Sumatera Barat dan provinsi Jambi. Beberapa pendekatan metodologis mendukung temuan kami: morfometrik linear tengkorak, morfometrik geometric 2D berbasis landmark, filogenetika molekuler menggunakan mtDNA dan enam ekson inti. Analisa multilokus kekerabatan antar spesies menempatkan tiga species baru ini dan C. aequicauda dalam satu klad dengan species endemik Jawa, C. monticola dan C. umbra. Walaupun dua taksa dari Gunung Singgalang ditemukan sebagai spesies saudara, salah satunya memiliki ukuran dua kali lebih besar dari yang lainnya, dan mereka berbeda dalam beberapa karakter morfologi lainnya, seperti panjang ekor, ukuran tengkorak, dan warna dan tekstur rambut. Taksa bersaudara yang baru saja bercabang tetapi memiliki morfologi berbeda yang hidup terisolasi di habitat “pulau,” seperti hutan pegunungan di Gunung Singgalang, merupakan hal yang tidak biasa pada mamalia, tetapi juga tercatat pada Crocidura lainnya di Jawa dan Kalimantan yang berdekatan; dua species baru ini merepresentasikan kasus pertama yang diketahui tentang fenomena ini di Sumatera. Hasil kami menjadikan jumlah Crocidura Sumatera menjadi sepuluh species, sembilan spesies endemik di pulau tersebut. Ketiga spesies baru tersebut tampaknya endemik di satu gunung saja dan tidak terdeteksi di survei serupa di gunung-gunung terdekat. Jika pola endemisme lokal ini umum, ini menunjukkan bahwa keanekaragaman mamalia Sumatera mungkin masih jauh dari estimasi sebenarnya, sebagian besar karena kurangnya survei mamalia kecil dan specimen museum dari kawasan tersebut.
Wildfire and postfire salvage logging are major drivers of forest succession in western North America. Although postfire landscapes support a variety of carnivore species, it is unclear how these animals respond to differing patterns and severities of burning, or to additional landscape change from postfire salvage logging. Open, early-seral habitats created by these disturbances are predicted to benefit generalists such as coyotes (Canis latrans) and weasels (Mustela spp.), but restrict the activity of forest specialists such as Canadaian Lynx (Lynx canadensis) and Pacific Marten (Martes caurina). We used winter track surveys, supplemented with remote cameras, to examine carnivore habitat use in and around large, mixed-severity burns in north-central Washington, United States (burned in 2006), and central British Columbia, Canada (burned in 2010, then partially salvage-logged; some areas reburned in 2017). At 10 to 13 years postfire, marten had similar detection rates across lightly and severely burned areas of the 2006 burn, as did coyotes. Marten selected lightly burned areas of the 2010 burn (6 to 9 years postfire) over higher burn severities, and selected burns over adjacent unburned forests. Weasels selected areas of higher burn severity on both landscapes, while Lynx selected lower burn severities. Weasels and coyotes selected areas with a greater proportion of salvage-logged habitat in the 2010 burn, while marten, lynx, and wolves (Canis lupus) avoided areas with salvage logging. Fishers (Pekania pennanti) showed no clear patterns of selection or avoidance in relation to burn severity or salvage logging. Burn severity strongly influences wildlife activity postfire; lightly burned residual habitats are critical for forest specialists. Postfire salvage logging alters carnivore communities and may hinder species that require structurally complex landscapes.
Natural processes and patterns are altered by human activity at different spatial and temporal scales, affecting species assemblages and population traits, modifying mechanisms or regulating dynamics at different scales. However, little is known about the influence of landscape structure on small mammal assemblages and populations on farms. Thus, in this work, we aimed to study the effect of landscape and environmental characteristics at the farm scale on the assemblage and populations of native and introduced small mammals in pig and dairy farms located in Buenos Aires province, Argentina. Our results showed that farms in contexts of higher environmental diversity at the landscape scale have higher species richness. Our results also showed that variations in assemblage composition were associated with the quantity of water body surfaces, cattle food, small mammal refugia, and impervious surfaces at the farm scale—and with woodland, grassland, and natural vegetation cover at the landscape scale. The abundance of commensal murids was higher on farms near towns, with higher vegetation cover at the farm scale and/or in landscape contexts with fewer crops. The abundance of Akodon azarae was higher on farms with a lower amount of cattle food at the farm scale and crop patches in the landscape. The abundance of Didelphis albiventris was higher during spring on farms with a low proportion of bare ground, while that of Lutreolina crassicaudata was higher on farms with high vegetation cover and a lower number of water body surfaces. These results show the relevance of multiscale determinants in the development of ecologically based management strategies to control pest small mammals.
Los procesos y patrones naturales se ven alterados por la actividad humana a distintas escalas espaciales y temporales, afectando tanto a los ensambles de especies como a sus poblaciones, modificando mecanismos o regulando sus dinámicas en distintas escalas. Poco es lo que se sabe acerca de la influencia de la estructura del paisaje sobre dichos ensambles y poblaciones. En este trabajo, estudiamos el efecto del paisaje y de variables ambientales dentro de las granjas sobre el ensamble y las poblaciones de pequeños mamíferos nativos e introducidos, en criaderos de cerdos y tambos de la provincia de Buenos Aires, Argentina. Nuestros resultados muestran que establecimientos en contextos de mayor diversidad ambiental a escala de paisaje poseen mayor riqueza específica. Además, muestran que las variaciones en la composición de los ensambles estuvieron asociadas a las proporciones de agua, comida para ganado, refugio para pequeños mamíferos y superficies impermeables a escala de granja y a las proporciones de árboles, pastizales y parches de vegetación natural a escala del paisaje. Las poblaciones de múridos comensales fueron mayores en establecimientos cercanos a las ciudades, con mayor cobertura vegetal alta y en contextos de paisajes sin cultivos. Las abundancias de Akodon azarae fueron menores en verano y mayores en establecimientos con menor proporción de comida para ganado y de parches de cultivo en el paisaje. La abundancia de Didelphis albiventris fue mayor durante la primavera en establecimientos con baja proporción de suelo desnudo, mientras que la abundancia de Lutreolina crassicaudata fue mayor en granjas con coberturas vegetales altas y con menor proporción de agua. Estos resultados muestran la pertinencia de los análisis multiescala para la elaboración de estrategias de manejo de pequeños mamíferos plagas basadas en fundamentos ecológicos.
Nielson Pasqualotto, Larissa L. Bailey, Danilo Boscolo, Thiago S.F. Silva, Nayra T. Rodrigues, Bruno H. Saranholi, Pedro M. Galetti Jr., Marcella do Carmo Pônzio, Vinicius Alberici, Adriano G. Chiarello
European Hare (Lepus europaeus), like many invasive species, have declined in much of their native range but flourished in non-native regions (e.g. South America). Previous studies suggested that loss of farmland heterogeneity due to agricultural intensification is the main driver of the species decline in its native range in Europe. Yet, little is known about the role of spatial and temporal heterogeneity and land cover types as predictors of European Hare local abundance in Neotropical agricultural landscapes. We hypothesized that spatial and temporal heterogeneity, rather than land cover types, would be the most influential predictors of hare local abundance in intensively managed Neotropical agricultural landscapes. We sampled 55 sites embedded within agricultural-dominated landscapes from southeastern Brazil with camera traps and transect surveys. Sites were selected along an uncorrelated gradient of native vegetation cover and compositional heterogeneity. We estimated the relative abundance of European hares using an occupancy model that accounts for imperfect detection of species induced primarily by variation in local abundance. We found that land cover diversity, sugarcane, and savanna cover were the best predictors of European Hare relative abundance. Hare relative abundance estimates were low and did not vary dramatically among sites, suggesting that this invader has not yet attained high local density in our study region. European Hare attained the highest relative abundance in agricultural landscapes that locally combine higher compositional heterogeneity, including sugarcane crops, and little to no native savanna. Areas with these combined features may represent the most important nascent foci, fostering ongoing northward spread of this invasive species in the Neotropics.
A lebre europeia (Lepus europaeus), assim como muitas espécies invasoras, tem declinado na maior parte da sua área de distribuição nativa mas prosperado em regiões onde a espécie foi introduzida (e.g. América do Sul). Estudos anteriores sugerem que a perda da heterogeneidade das áreas agrícolas, devido à intensificação da agricultura, é o principal fator responsável pelo declínio da espécie em sua área nativa na Europa. No entanto, pouco se sabe sobre o papel da heterogeneidade espacial e temporal e dos tipos de cobertura do solo como preditores da abundância local da lebre europeia em paisagens agrícolas Neotropicais. Nós hipotetizamos que a heterogeneidade espacial e temporal, ao invés dos tipos de cobertura do solo, seriam as preditoras mais importantes da abundância local da lebre em paisagens agrícolas Neotropicais intensivamente manejadas. Nós amostramos 55 sítios inseridos em paisagens agrícolas localizadas no sudeste do Brasil utilizando armadilhamento fotográfico e transecções. Os sítios foram selecionados a partir de um gradiente não correlacionado de cobertura por vegetação nativa e heterogeneidade de composição. Nós estimamos a abundância relativa da lebre usando um modelo de ocupação que lida explicitamente com detecção imperfeita da espécie induzida principalmente pela variação em sua abundância local. Nós encontramos a diversidade de tipos de cobertura do solo (heterogeneidade composicional) e a cobertura por savana e cana-de-açúcar como principais preditores da abundância relativa da lebre europeia. As estimativas de abundância relativa da lebre foram baixas e não variaram muito entre os sítios amostrados, sugerindo que esse invasor pode ainda não ter atingido alta densidade local em nossa região de estudo. A lebre europeia atingiu maior abundância relativa em paisagens agrícolas que combinam localmente alta heterogeneidade composicional, incluindo cana-de-açúcar, e pouca ou nenhuma savana nativa. Áreas com essas características combinadas podem representar importantes focos nascentes desse invasor, facilitando a presente expansão geográfica da lebre europeia nos Neotrópicos em direção ao norte.
Increasing urbanization and consequent habitat fragmentation and loss call for studies of the influence of urbanization on native fauna. South American Coati (Procyonidae: Nasua nasua) live in groups and are common in urban areas of South America. Here, we aimed to understand how coatis occupy and select space, and whether they change their circadian activity in an urban environment. We estimated home range sizes, verified any overlap, and evaluated the effects of sex and weight on home range size. We also described coati activity patterns associated with habitat selection. Animals established their home ranges only within the study area, with few exploratory exits to surrounding areas. Furthermore, our home range estimates of 0.66 km2 are lower than previously found in natural habitats. We did not observe an effect of sex or weight on home range size. Coatis predominantly selected forested areas and explored houses only early in the morning. We suggest that this demonstrates the need for forested areas for survival of the species. Regarding activity patterns, coatis were active only during the day, as described for the species in its natural environment. Human barriers—in addition to human refuse that serves as food—could reduce the home range sizes. Our data demonstrate differences in home range size, but not circadian activity or habitat selection when compared to coatis in their natural environment.
A crescente urbanização e consequente fragmentação e perda de habitat tornam urgente o estudo sobre a influência da urbanização na fauna nativa. O quati sul-americano (Procyonidae: Nasua nasua) vive em grupos e é uma espécie comum em áreas urbanas da América do Sul. Nesse estudo, buscamos entender como os quatis ocupam e selecionam o espaço e se alteram sua atividade circadiana em um ambiente urbano. Nós estimamos o tamanho da área de vida, verificando a sobreposição entre machos e fêmeas, e avaliamos os efeitos do sexo e do peso sobre o tamanho da área de vida. Também descrevemos o padrão de atividade e a variação na seleção de habitat. Os quatis estabeleceram suas áreas de uso apenas dentro da área de estudo, com poucas saídas exploratórias para as áreas do entorno. Obtivemos estimativas de área de vida de 0,66 km2, inferior ao encontrado anteriormente no ambiente natural. Além disso, não observamos efeito do sexo e peso sobre o tamanho da área de vida. Os quatis selecionaram predominantemente áreas florestais e exploraram as casas apenas no início da manhã, o que sugere a necessidade de áreas florestadas para a sobrevivência da espécie. Em relação ao padrão de atividade, os quatis foram ativos apenas durante o dia, conforme descrito para a espécie em seu ambiente natural. Barreiras humanas, além de dejetos humanos que servem como alimento, podem reduzir o tamanho da área de vida. Nossos dados demonstram diferenças no tamanho da área de vida, mas não na atividade circadiana e na seleção de habitat quando comparados aos quatis no ambiente natural.
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