Secondary forests are now prominent features in Neotropical landscapes, yet little is known about their conservation value for nonvolant mammalian communities. We performed a 20-month study using transect walks to survey the nonvolant mammal fauna in primary and secondary forests at La Selva Biological Station in the Caribbean lowlands of northeastern Costa Rica. We found that secondary forests can hold complex mammalian communities and no species exhibited habitat preferences between primary and secondary forests. With few exceptions, behavioral and group dynamic characteristics of mammal species were similar between forest types. Our research allows us to address methodological questions and assess the effectiveness of transect sampling. Monthly detection rates vary widely by species and likely reflect short-term changes in behavior rather than population fluctuations. Air temperature and rainfall are the factors most associated with monthly detection rates for various species. Small-scale areas of higher and lower use are evident for several species. Neither time of morning for surveys nor number of observers per trail affects detection rate. We report current abundances for the most commonly observed species and note generally lower densities in the Caribbean lowlands than elsewhere in the Neotropics. This research highlights that in less seasonal, evergreen forests climatic factors can still affect mammalian behavior. Overall, we find that secondary forests are of high conservation value and that transect walks are an effective methodology to sample many nonvolant mammal species, and we present recommendations on how to sample properly to conduct rigorous and long-term studies.

Marine predator populations are sensitive to temporal variation in prey availability, but prey dynamics are often difficult to quantify. Long-term measures of offspring growth is a useful performance attribute to gauge the potential demographic direction for such predator populations, especially where other metrics (e.g., population size estimates) are lacking. Subantarctic fur seal (Arctocephalus tropicalis) females are central place foragers during a protracted lactation period, and their foraging success determines the growth and vitality of their offspring. Using data spanning over 2 decades, we assessed geographic and temporal variation in growth rates and weaning mass of subantarctic fur seal pups at 2 of the species' principal populations (Gough and Marion islands) and identified environmental conditions that may, through assumed bottom-up mechanisms, affect body mass at weaning. While Marion Island pups grew at an average rate of between 0.040 and 0.067 kg/day early in lactation (comparable to conspecific growth at Amsterdam Island), the mean growth rate at Gough Island (approximately 0.030kg/day) was lower than the growth rate represented by the bottom 5% of the body mass distribution at Marion Island. Notwithstanding substantial interannual variability, we found support for a negative trend in weaning mass at both populations, suggesting a rise in limiting factors that is hypothesized to relate to concurrent local population size increases. Weaning mass tended to be higher when sea surface temperatures were warmer (with a stronger positive effect at Gough Island) and during positive phases of the Southern Oscillation Index (La Niña events), with a stronger positive effect in males. Given the low weaning mass of Gough Island fur seal pups, continued population growth here seems unlikely. While density-dependent regulation appears to have increased in strength at Marion Island, terminating rapid population growth, current weaning weights remain above the physiological limits of growth in subantarctic fur seals.

A growing body of evidence showing that individuals of some social species live in non-kin groups suggests kin selection is not required in all species for sociality to evolve. Here, we investigate 2 populations of Octodon degus, a widespread South American rodent that has been shown to form kin and non-kin groups. We quantified genetic relatedness among individuals in 23 social groups across 2 populations as well as social network parameters (association, strength, and clustering coefficient) in order to determine if these aspects of sociality were driven by kinship. Additionally, we analyzed social network parameters relative to ecological conditions at burrow systems used by groups, to determine if ecological characteristics within each population could explain variation in sociality. We found that genetic relatedness among individuals within social groups was not significantly higher than genetic relatedness among randomly selected individuals in both populations, suggesting that non-kin structure of groups is common in degus. In both populations, we found significant relationships between the habitat characteristics of burrow systems and the social network characteristics of individuals inhabiting those burrow systems. Our results suggest that degu sociality is non-kin based and that degu social networks are influenced by local conditions.

Recent recolonization of mountain lions (Puma concolor) into the Little Missouri Badlands of North Dakota has led to questions regarding the potential impacts of predation on prey populations in the region. From 2012 to 2013, we deployed 9 real-time GPS collars to investigate mountain lion feeding habits. We monitored mountain lions for 1,845 telemetry-days, investigated 506 GPS clusters, and identified 292 feeding events. Deer (Odocoileus spp.) were the most prevalent item in mountain lion diets (76.9%). We used logistic regression to predict feeding events and size of prey consumed at an additional 535 clusters. Our top model for predicting presence of prey items produced a receiver operating characteristic score of 0.90 and an overall accuracy of 81.4%. Application of our models to all GPS clusters resulted in an estimated ungulate kill rate of 1.09 ungulates/week (95% confidence interval [CI] = 0.83–1.36) in summer (15 May–15 November) and 0.90 ungulates/week (95% CI = 0.69–1.12) in winter (16 November–14 May). Estimates of total biomass consumed were 5.8kg/day (95% CI = 4.7–6.9) in summer and 7.2kg/day (95% CI = 5.3–9.2) in winter. Overall scavenge rates were 3.7% in summer and 11.9% in winter. Prey composition included higher proportions of nonungulates in summer (female = 21.5%; male = 24.8%) than in winter (female = 4.8%; male = 7.5%). Proportion of juvenile ungulates in mountain lion diets increased during the fawning season (June–August) following the ungulate birth pulse in June (June–August = 60.7%, 95% CI = 43.0–78.3; September–May = 37.2%, 95% CI = 30.8–43.7), resulting in an ungulate kill rate 1.61 times higher (1.41 ungulates/week, 95% CI = 1.12–1.71) than during the remainder of the year (0.88 ungulates/week, 95% CI = 0.62–1.13). Quantifying these feeding characteristics is essential to assessing the potential impacts of mountain lions on prey populations in the North Dakota Badlands, where deer dominate the available prey base and mountain lions represent the lone apex predator.

Identifying limiting factors is fundamental to understanding and conserving mammals, yet it often requires longterm data for long-lived species. Numerical changes of migratory caribou (Rangifer tarandus), for example, may unfold over decades, but few studies have examined habitat use at similar timeframes. We analyzed multiple decades of habitat use by caribou in Newfoundland, Canada, coincident with their numeric growth (r = 0.064 in 1980s, 1990s) and decline (r = -0.099 in 2000s). We examined 2 scales: selection of land cover, based on radiotracking of 520 adult females, and diet, based on microhistological analysis of feces and age-specific tooth wear from jawbones of harvested animals. Caribou responded at both scales. In contrast to previous decades, females during the population decline used proportionally less open coniferous and closed coniferous forests, they used more shrublands (in fall and winter) and barrens, open habitats with greater vascular plant resources. Patterns of selection also changed from nonselection to avoidance of open coniferous forest and from avoidance to nonselection or preference of barrens. The proportion of dietary moss increased at the expense of deciduous shrubs, especially during spring and summer and of ericaceous shrubs, graminoids, and lichens during winter. Teeth of both sexes exhibited premature wear, likely indicative of abrasion from low-quality forages and cropping of foods near the ground. These patterns mirror other responses, including declines in calf weight, female body size, number of male antler points, herd affinities, and time spent on the summer grounds. We surmise that they reflect density-dependent forage limitation of this island population.

Morphological character data are inadequate to resolve the evolutionary relationships of the didelphid genus Chacodelphys, which previous phylogenetic analyses have alternatively suggested might be the sister taxon of Lestodelphys and Thylamys (tribe Thylamyini) or of Monodelphis (tribe Marmosini) in the subfamily Didelphinae. Because fresh material of Chacodelphys is unavailable, we extracted DNA from microscopic fragments of soft tissue adhering to the 95-year-old holotype skull of C. formosa. Phylogenetic analyses of the resulting sequence data convincingly resolve Chacodelphys as the sister taxon of Cryptonanus, a genus with which it had not previously been thought to be closely related. This novel clade (Chacodelphys Cryptonanus) belongs to an unnamed thylamyine lineage with Gracilinanus and Lestodelphys Thylamys, but relationships among these taxa remain to be convincingly resolved.

Pocket gophers of the genus Orthogeomys show unusually high morphological and ecological diversity compared to other genera in the family Geomyidae. Whereas this diverse group once was divided into 3 genera (Merriam 1895), a revision by Russell (1968) recognized only Orthogeomys, with Merriam's original genera relegated to subgeneric status as Heterogeomys, Macrogeomys, and Orthogeomys. Recent studies have called into question the monophyly of Orthogeomys, as well as the validity of 4 currently recognized Orthogeomys species. To date, the taxonomic validity of only 1 of these species has been verified (Hafner et al. 2014). In this analysis, the first to include all 11 recognized species of the genus, we examine 3 mitochondrial and 2 nuclear gene sequences (4,352 base pairs) and analyze cranial morphology to explore relationships within the genus. Our data support a taxonomic revision that restricts the genus Orthogeomys to a single species (O. grandis) and combines the subgenera Heterogeomys and Macrogeomys into the resurrected genus, Heterogeomys (7 species). In addition, 3 currently recognized species of Orthogeomys are synonymized as follows: O. cuniculus with O. grandis; H. thaeleri with H. dariensis; and H. matagalpae with H. cherriei. A synonymy and a key to the species of the genera Orthogeomys and Heterogeomys are provided.

Las tuzas del género Orthogeomys muestran una diversidad morfológica y ecológica inusual en comparación con otros géneros de la familia Geomyidae. Aunque este diverso grupo fue alguna vez dividido en 3 géneros (Merriam 1895), la revisión de Russell (1968) reconoció solo a Orthogeomys, mientras que los géneros originales de Merriam fueron relegados a estatus subgenérico como Heterogeomys, Macrogeomys y Orthogeomys. Estudios recientes han cuestionado la monofilia de Orthogeomys, así como la validez de 4 de las especies actualmente reconocidas. A la fecha, la validez taxonómica de sólo una de estas especies ha sido verificada. En este análisis, el primero en incluir las 11 especies reconocidas en el género, examinamos secuencias de 3 genes mitocondriales y 2 nucleares y analizamos la morfología craneal para explorar las relaciones dentro del género. Nuestras 4,352 pares de bases de secuencias de ADN apoyan una revisión taxonómica que retiene al género Orthogeomys (incluyendo sólo a O. grandis) y combina los subgéneros Heterogeomys y Macrogeomys en un género recuperado, Heterogeomys (7 especies). Además, 3 especies de Orthogeomys actualmente reconocidas son sinonimizadas de la siguiente forma: O. cuniculus con O. grandis; H. thaeleri con H. dariensis; y H. matagalpae con H. cherriei. Se incluye sinonimia y una clave para las especies de los géneros Orthogeomys y Heterogeomys.

Studies about habitat fragmentation, in terms of how it affects gene flow and genetic variability, have traditionally been conducted on island-like systems in which the remaining habitats form patches embedded in a matrix. However, in agroecosystems, remaining habitats usually form linear strips along fence lines, roads, and water courses (“border” habitats). We used the rodent Calomys venustus, a species inhabiting borders in central Argentina agroecosystems, as a model to address how genetic variability is structured in linear habitats. A total of 359 rodents were captured seasonally from spring 2005 to winter 2006. Genetic variability at microsatellite loci was uniformly high, despite significant variation in population size during the sampling period. Genetic differentiation, spatial autocorrelation, and causal modeling analyses suggested that dispersion patterns in this species depend mainly on geographic distance, with unfavorable habitat like dirt roads and crop fields posing only weak (or no) resistance to dispersal. Small-scale spatial genetic structure was related to different space use patterns by females and males. Our results showed that, although greatly reduced in area, border habitats can support stable populations of species without loss of either variability or genetic connectivity.

Marine mammal species were exploited worldwide during periods of commercial sealing in the 18th and 19th centuries. For many of these species, an estimate of the pre-exploitation abundance of the species is lacking, as historical catch records are generally scarce and inaccurate. Genetic estimates of long-term effective population size provide a means to estimate the pre-exploitation abundance. Here, we apply genetic methods to estimate the long-term effective population size of the subantarctic lineage of the New Zealand sea lion (NZ sea lion), Phocarctos hookeri. This species is predominantly restricted to the subantarctic islands, south of mainland New Zealand, following commercial sealing in the 19th century. Today, the population consists of ∼9,880 animals and population growth is slow. Auckland Island breeding colonies of NZ sea lion are currently impacted by commercial trawl fisheries via regular sea lion deaths as bycatch. In order to estimate sustainable levels of bycatch, an estimate of the population's carrying capacity (K) is required. We apply the genetically estimated long-term effective population size of NZ sea lions as a proxy for the estimated historical carrying capacity of the subantarctic population. The historical abundance of subantarctic NZ sea lions was significantly higher than the target values of K employed by the contemporary management. The current management strategy may allow unsustainable bycatch levels, thereby limiting the recovery of the NZ sea lion population toward historical carrying capacity.

Males typically adjust their reproductive strategies based on the perceived density and relative abilities of nearby competitors. In high-density populations, repeated encounters facilitate reliable, learned associations between individuals and their relative competitive abilities. In contrast, opportunities to form such associations are limited when densities are low or in flux, increasing the risk that individuals will unintentionally engage in potentially costly interactions with higher-quality or aggressive opponents. To maximize their fitness, individuals in lowdensity and fluctuating populations therefore need a general way to assess their current social environment, and thus their relative competitive ability. Here, we investigate how olfactory social signals (scent marks) might perform this function. We manipulated the perceived social environment of isolated, male house mice (Mus domesticus) via their periodic contact with scent marks from 3 or 9 male conspecifics, or a control of no scents, over 15 days. We then paired them with an unknown opponent and examined how the diversity of recent scent contact mediated their behavior towards dominant or subordinate opponents. There was an overall pattern for increasing scent diversity to significantly reduce male mice's aggression (tail rattling and lunging) towards their opponents, and also their willingness to engage in reciprocal investigation. Such cautiousness was not indicative of perceived subordinance, however; the diversity of recent scent contact did not affect mice's investigation of their opponent's scents, and some measures of aggression were greater when mice faced dominant opponents. These results suggest that house mice can use scent signals to assess their current social environment in the absence of physical interactions, modifying their behavior in ways that are predicted to reduce their risks of injury when the likelihood of encountering unknown opponents increases.

Ocelots (Leopardus pardalis) are common in lowland forests of Amazonia. We used camera traps to document the occurrence and activity of ocelots at a site in eastern Ecuador during 2005–2012 (15,058 trap-days). We accumulated 384 independent images of 16 males (147 images), 19 females (234 images), and 3 not assigned to individual or sex. Individuals varied in number of images (1 to > 50), number of camera locations (1–8), and number of months from first to last image (1–85). Photographic rate varied across years, from 15.3 to 29.9/1,000 trap-days in 2006 and 2010, respectively. Males and females were primarily active at night and showed similar hourly patterns of activity. Up to 3 individual males and 4 individual females were recorded at different camera locations each year. Resident males typically were photographed at more locations (mean of 4.1) than females (mean of 3.2). Results indicate that multiple ocelots, of both sexes, may be found within a relatively small (∼650 ha) area of lowland forest in eastern Ecuador and emphasize the importance of the region for conservation of ocelots and other species.

In the face of climate change, there is a growing need for research into the ability of organisms to persist at the limits of their bioclimatic envelope. American pikas (Ochotona princeps) have emerged as a focal mammalian species for investigating extinction risk related to climate change; however, most studies have occurred in characteristic alpine talus habitat within the range core. In the Columbia River Gorge (CRG), Oregon, American pikas inhabit low-elevation talus slopes previously considered outside the species' bioclimatic range. We used microsatellite genotypic data to reconstruct levels of genetic variation, population connectivity, and demographic history at 11 CRG sites spanning an elevational gradient (104–1,292 m). Sampled sites separated into 2 genetic clusters largely explained by elevation, topography, and geographic proximity, with pairwise estimates of differentiation and migration rates suggesting little gene flow may be occurring. Sites were characterized by levels of allelic richness and heterozygosity substantially lower than values reported at characteristic alpine sites from the range core. Evidence of recent demographic contraction was found almost exclusively at high-elevation sites despite these areas being considered refuges from climate warming in more typical habitat. Given their unique genetic characteristics and persistence in an atypical environment, the CRG pika populations likely constitute a significant component of intraspecific biodiversity with high conservation value.

Human/carnivore conflicts are common across the globe, and with a growing human population, this conflict is likely to increase as the space available to large carnivores is reduced. In South Africa, many small (< 400 km²), fenced protected areas have reintroduced persecuted carnivores, such as brown hyenas (Hyaena brunnea). These reserves have great potential to conserve brown hyena populations; consequently, understanding the limitations that small, fenced reserves impose on space use patterns is needed. We investigated the home range (95% fixed kernel utilization distributions) and landscape determinants of habitat selection using resource selection functions for 10 brown hyenas in 3 separate fenced reserves. Home range sizes were consistently smaller in 2 of the reserves when compared to the third. Considerable variation in the selection of habitat features exists among individual brown hyenas and reserves. The most important landscape determinant driving brown hyena space use was distance to roads, with brown hyenas observed closer to roads when compared to random locations within their ranges. If this relationship with roads holds outside of protected areas, it could represent a considerable threat to the species. Thus, obtaining a better understanding of the influence of roads on brown hyenas represents an important focus for future research.

One way in which animals coexist is through temporal separation of feeding activities. This separation directly reduces interference competition, but potentially not exploitive competition. To reduce exploitive competition, coexisting species tend to utilize different microhabitats and/or achieve different feeding efforts across microhabitats. However, 1 factor that has generally not been considered with regards to its impacts on competition, and thus coexistence, is predation risk. As different predators are active during the day and at night, the location of safe areas across the landscape can vary temporally. If so, then temporally separated prey species would likely forage in different areas thus reducing exploitive competition. However, if predation risk across the landscape is similar for nocturnal and diurnal species, then both could restrict their foraging to the same microhabitats, thus increasing exploitive competition. To explore these alternative possibilities, we manipulated grass height in an African grassland to create microhabitats that varied in predation risk. We then estimated perceived predation risk of both nocturnal and diurnal rodents in these microhabitats by recording giving-up densities (GUDs) in artificial resource patches. We found that despite differences in predators, both nocturnal and diurnal rodents preferred feeding in the same microhabitats, and they achieved similar feeding efforts within these microhabitats. This suggests that despite the prevention of interference competition through temporal partitioning, the spatial similarities in perceived predation risk in relation to cover likely increase exploitive competition between these rodents. However, as both nocturnal and diurnal rodents were present in the study area, it is likely that some other mechanism (e.g., varied diets) allows them to coexist.

One of Risso's dolphin's distinctive characteristics is the tendency to “lighten” with age due to the accumulation of unpigmented scars. These accumulated scars may provide an indication of age. Photographic skin recaptures gathered from 61 free-ranging animals over a period of 15 years were analyzed to develop a skin classification model in 6 skin stages. Classification of photographic skin captures following this model was tested by 15 experts and 13 nonexpert rankers, with a general probability of agreement of 79%. The duration of each skin stage was estimated using a statistical model based on the recorded dates in which individual animals were known to have entered and/or exited a given stage. A Bayesian approach was used to combine available photographic skin recapture data using expert knowledge as prior to predict the duration for each skin stage and thus the mean age at each stage. Results suggest that animals may live more than 45 years, which is in agreement with published information based on dental layers. The proposed skin stages can be correlated with reproduction, with the transition to stage 3 linked to the onset of maturity. Adult females are less scarified than males and were not observed in the whiter skin classes. The proposed skin stage model is noninvasive and easy to apply and could be a valuable tool in further studies of population structure and dynamics of Risso's dolphins.

Females have larger pelves than males among eutherians to mitigate obstetrical difficulty. This study addresses 3 issues concerning pelvic sexual dimorphism using 8 species that are sexually monomorphic in nonpelvic size: Aotus azarae, Castor canadensis, Dasypus novemcinctus, Hylobates lar, Saguinus geoffroyi, Sciurus carolinensis, Sylvilagus floridanus, and Urocyon cinereoargenteus. Using published data to compute the index of relative newborn body mass (RNBM = [newborn body mass/adult female body mass] 100%) for 266 eutherian species, A. azarae, H. lar, and S. geoffroyi are characterized as giving birth to relatively large newborns and the other 5 species as giving birth to relatively small newborns. The 3 issues are, compared to species giving birth to relatively small newborns, whether species that give birth to relatively large newborns have 1) higher magnitude of pelvic sexual size dimorphism (SSD), 2) lower prevalence of pelvic joint fusion, and 3) dissociation between pelvic and nonpelvic sizes. Nine measures of the pelvis were taken, and fusion of interpubic and sacroiliac joints was observed. Species grouped by high and low RNBM do not differ significantly in magnitude of SSD of pelvic inlet circumference. Species with high RNBM have significantly lower prevalence of interpubic joint fusion than those with low RNBM. Sexes do not differ in their multiple correlation coefficients between inlet circumference and nonpelvic body size in 7 of 8 species. Results suggest that 1) there are multiple anatomical pathways for pelvic obstetrical sufficiency, 2) an unfused interpubic joint is obstetrically advantageous, and 3) relative newborn size does not change the association between pelvic and nonpelvic size in females and males.

Despite exceptionally high levels of biodiversity and endemism found in Madagascar, much of its wildlife remains little studied, particularly the carnivore community. The recently described, little-known black forest cat (locally known as “fitoaty”) is believed to be restricted to NE Madagascar and has been investigated only through village surveys and anecdotal accounts. From 2008 to 2012, we photographically sampled 7 forest sites with varying degrees of degradation and fragmentation across Makira Natural Park with the goals of: 1) estimating landscape occupancy for fitoaty (Felis spp.), 2) identifying variables influencing fitoaty occupancy, and 3) comparing fitoaty and feral cat (Felis spp.) occupancy across the landscape. We observed higher occupancy for fitoaty, minimal co-occurrence between fitoaty and feral cats (n = 2 sites), and strong divergence in habitat use. We provide the 1st assessment of fitoaty morphology, including comparisons with anecdotal reports, and the 1st population assessment of Madagascar's exotic cat community with insights into factors associated with carnivore population trends in Madagascar. We suggest the described fitoaty is a phenotypically different form of the feral cat, but additional research is needed. Targeted management plans are needed to diminish the spread and potential negative effects of invasive cats across this important biologically diverse ecoregion.

Pale foxes (Vulpes pallida) have a widespread distribution across the Saharan-Sahel in northern Africa, but little is known about their ecology and natural history. Here, we provide the 1st ecological information on the species. We captured and radio-collared 10 pale foxes in the Termit & Tin Toumma National Nature and Cultural Reserve of east Niger. The adult body mass (1.20 ± SD 0.18 kg, n = 6) was about half of what was previously reported, confirming this species as one of the smallest canids in the world. Body measurements were relatively similar between sexes, suggesting little if any sexual dimorphism. Mean ± SD home range size (n = 6) was 6.79 ± 3.58 km² using 100% minimum convex polygon and 5.62 ± 3.11 km² using 95% fixed kernel density estimator. Overlap between adjacent pale fox ranges was generally low (mean overlap index = 0.11 ± 0.22), with nearly exclusive core areas (mean overlap index = 0.02 ± 0.06), suggesting pale foxes are territorial. Overall, the spatial ecology of pale foxes showed similar characteristics to other Vulpes species, especially those inhabiting arid and semiarid environments.

In comparison to the mainland, populations of rodents on islands are often characterized by a suite of life history characteristics termed the “island syndrome.” Populations of rodents introduced to islands are also well known for their impacts on native species that have evolved in the absence of mammalian predators. We studied the ecology and behavior of introduced house mice Mus musculus on Gough Island where they are the only terrestrial mammal and where their predatory behavior is having a devastating impact on the island's burrowing petrel (order Procellariiformes) population and the Critically Endangered Tristan albatross Diomedea dabbenena. Mice on Gough exhibit extreme features of the island syndrome, including: a body mass 50–60% greater than any other island mouse population, peak densities among the highest recorded for island populations, and low seasonal variation in numbers compared to other studied islands. Seasonal patterns of breeding and survival were linked to body condition and mass, and mice in areas with high chick predation rates were able to maintain higher mass and condition during the winter when mouse mortality rates peak. Within-site patterns of chick predation indicate that proximity to neighboring predated nests and nesting densities are important factors in determining the likelihood of predation. We conclude that selection for extreme body mass and predatory behavior of mice result from enhanced overwinter survival. Small mammal populations at temperate and high latitudes are normally limited by high mortality during the winter, but on Gough Island mice avoid that by exploiting the island's abundant seabird chicks.

Male-biased dispersal and female philopatry are common traits among social mammals, often leading to elevated relatedness within social groups. However, exceptions do occur, with documented cases of female-biased dispersal, dispersal by both sexes, and philopatry of both sexes. In this study, we examined levels of dispersal and relatedness based on analyses of the mitochondrial D-loop and 12 nuclear microsatellite markers in the woodland specialist Ussuri tube-nosed bat (Murina ussuriensis), a relatively widespread, yet locally rare species that is thought to be threatened by loss of its forest habitats across its range. A total of 85 individuals were captured in lowland temperate forest on the island of Yakushima and 28 individuals in montane forest in Hokkaido, Japan. In the former, haplotypes showed extreme spatial clustering among females consistent with strong philopatry, but spatial mixing among males suggesting dispersal over short distances. These findings were broadly supported by microsatellite analyses, which indicated considerable genealogical structure within sampling locations but a lack of spatial structure, again indicating that some gene flow does occur in one or both sexes. The Hokkaido data, although limited, did not show these patterns and instead suggest that differences in environmental and behavioral variables may influence movement ecology of individuals at these 2 sites and consequently fine-scale genetic structure within this species.

Changes in habitat composition and structure along natural agricultural habitat gradient affect spatial ecology of carnivores at both intraspecific and interspecific levels. An important prerequisite for the conservation and management of habitat specialists is a sound understanding of how they use indigenous habitats within fragmented landscapes. We present the 1st comprehensive study on home range, overlap, and resource selection of 16 radiocollared servals (Leptailurus serval) in the Drakensberg Midlands, South Africa. Servals (11 males and 5 females) were livetrapped and radiotracked between May 2013 and August 2014 covering 4 seasons (winter, spring, summer, and autumn). Mean annual home range estimates (95% and 50% fixed kernel [FK], respectively) for males (38.07 km²; 8.27 km²) were generally larger than for females (6.22 km²; 1.04 km²). Although male core ranges varied slightly in spring, overall serval home ranges were stable across seasons. There was considerable intersexual home range overlap (> 85%), whereas intrasexual overlap was rare (< 10%). Home range size decreased with increase in age and less availability of wetland, while it increased in males at both levels (95% FK and 50% FK). For both sexes, Manley's selection index indicated that natural habitats including wetlands and forest with bushland ranked higher than all other habitat classes. However, forested habitat was used approximately 2 times more frequently by males than females whereas cropland was avoided by both sexes. Overall, wetlands were ranked highest, followed by forest with bushland, grassland, plantations, and cropland in terms of serval resources selection. Our results emphasize that natural habitats, mainly wetlands and forests with bushland, are important predictors of spatiotemporal habitat use of servals in the agricultural mosaics of South Africa.

We describe the behavior in captivity of the dusky shrew-opossum Caenolestes fuliginosus from 17 specimens captured at Finca La Martinica (Colombia), which were kept alive in plastic terraria for different periods of time (between 1 and 12 consecutive days). We found that C. fuliginosus can climb and jump well and uses its nonprehensile tail as a support when climbing. Feeding observations showed a preference towards an animalivorous diet, which included moths/butterflies (Insecta, Lepidoptera), stick-insects (Insecta, Phasmatoidea), flatworms (Platyhelminthes, Turbellaria), earthworms (Annelida, Oligochaeta), frogs (Amphibia, e.g., Pristimantis sp.), and dead rodents (Rodentia, Sigmodontinae, e.g., Microryzomys sp., Thomasomys sp.). Individuals were active throughout the day and night, with no indication of daily torpor. Our observations showed C. fuliginosus is not aggressive towards congeners and often aggregates during rest, especially when several individuals are placed together. Unlike other New World marsupials, C. fuliginosus showed nonagonistic group feeding behavior when consuming carcasses. Stereotyped behavior patterns (e.g., grooming) were not frequently observed. Our work provides comparative information for further studies on caenolestids and other New World marsupials.

Animal mating systems are driven by the temporal and spatial distribution of sexually receptive females. In mammals, ground-dwelling squirrels represent an ideal clade for testing predictions regarding the effects of these parameters on male reproductive strategies. While the majority of ground squirrel species have a short, highly synchronous annual breeding season that occurs immediately after females emerge from hibernation, the Mexican or Rio Grande ground squirrel (Ictidomys parvidens) differs markedly in having an extended mating season (2 months) and a long delay between emergence from hibernation and female receptivity (1–2 months). Both traits are expected to favor polygyny by increasing the chances that a male can secure matings with multiple females (e.g., females that come into estrus on different days). To test this prediction, we used microsatellite markers to characterize the mating system of a population of Rio Grande ground squirrels from Carlsbad, New Mexico. Our analyses indicated a high frequency of multiple paternity of litters in this population. Paternity was not related to spatial overlap between known mothers and assigned fathers, suggesting that territory defense is unlikely to be an effective male reproductive strategy in the study population. Dominance interactions among males were frequent, with heavier males typically winning dyadic interactions. Surprisingly, however, males with lower dominance scores appeared to have higher reproductive success, as did males that were active over a greater extent of the study site. Collectively, these results suggest that the mating system of the Rio Grande ground squirrel is best described as scramble competition polygyny, with the primary male reproductive strategy consisting of searching for estrous females. Similar patterns of male-male competition have been reported for a few other ground squirrel species, providing potentially important opportunities for comparative studies of the factors favoring this form of male reproductive strategy.

Human population growth is a major threat to the biodiversity of mammals in China. Rapid development of infrastructure, pollution, and poor enforcement of environmental laws in China have altered the landscape and accelerated the extinction rates of mammals. To maintain biodiversity and conserve the mammals of China, it is essential to develop monitoring protocols for species of concern that are efficient, cost-effective, and current. It is now common practice for ecologists to survey mammals of interest using noninvasive sampling methods. These sampling techniques are affordable, require no handling of the target animals, and generally yield large samples. In China, such sampling methods have rarely been used and evaluated. For this study, we recorded the behavior of masked palm civets (Paguma larvata) and Siberian weasels (Mustela sibirica) to determine their relative preference for using different hair-snaring devices and evaluated the effectiveness of each device at collecting hair. Our goal was to determine which genetic sampling method(s) should be used to study masked palm civets and Siberian weasels in the future in Southwest China. In March–June of 2014, we monitored 13 hair-snare stations throughout the Main Valley of Laohegou Nature Reserve, Sichuan Province, China. Genetic analysis revealed that we collected 373 hair samples from civets and 47 hair samples from weasels over 104 and 26 sessions, respectively. Both civets and weasels seemed to prefer lure sticks to ground cubbies; however, the latter were more effective at collecting civet hair. Although glue sheets from lure sticks collected large samples of guard hair (> 10), no device in its current design was consistently effective at collecting weasel hair. We suggest researchers in Southwest China use ground cubbies as described in this study to collect hair from masked palm civets and test other cubby designs (e.g., longer gun brushes or smaller in size) for collecting hair from Siberian weasels.

Home range studies provide significant insights on social organization and interactions, limiting resources and habitat use. Knowledge on home range and habitat use by Guiana dolphins, Sotalia guianensis, is still scarce. The aim of this study was to identify and analyze individual's home ranges of Guiana dolphins in the Cananéia Estuary (∼25°03′S, 47°55′W), located in southeastern Brazil. Photo-identification efforts were conducted between 2000 and 2010. From a total of 135,918 pictures taken, 34,086 (25%) were useful for individual identification. Two-hundred and five individuals were cataloged based on permanent notches along dorsal fin borders. Of the cataloged individuals, 31 had been identified a minimum of 20 times, on distinct dates, prior to this analysis. Home ranges were estimated for these individuals using 4 methods: minimum convex polygon (MCP), adaptive kernel with least-squares cross-validation (AKLSCV), fixed kernel with reference bandwidth (FKHREF), and fixed kernel with least-squares cross-validation (FKLSCV). The sizes of the estimated home ranges varied between 2.2 and 43.8 km² ( = 17.5 km²) with MCP, between 0.8 and 82.5 km² ( = 15.6 km²) with AKLSCV, between 3.9 and 244 km² (X = 72.4 km²) with FKHREF, and from 0.6 to 70.6 km² ( = 13.5 km²) with FKLSCV Significant differences in size and shape of the generated areas were detected when comparing the 4 tested methods. Variation of individual's home range sizes and an extensive overlap among home ranges of different Guiana dolphins in the Cananéia Estuary provide evidence that the region supports important resources for this species. Therefore, preventing habitat loss in this region is essential to guaranteeing the persistence of this population.

Selective pressure from the environment on species may select adaptations as a whole, including the specific context of acoustics. Some authors report that the acoustic repertoire of Sotalia guianensis presents dialects as a geographical reflection. However, others propose that the environmental characteristics are the factor that imposes these variations. The present study evaluated if S. guianensis modifies its sound emissions at the Curral Cove (CC) and the Guaraíras Lagoon Complex (GLC), different habitats at similar latitudes. At the GLC, dolphins use higher whistle frequencies as well as higher number of click per second, facts that may be related to sound precision for communication between individuals and prey capture. Variations in the dolphins' sounds may be related to differences in the environments such as natural background noise—biotic and abiotic—and characteristics such as turbidity, temperature, salinity, and modification in sound propagation due to depth and bottom properties. The pulsed calls' sound category did not present modification between habitats probably due to context in which they are used since they occur during high physical contact. It is possible that the variation of the sound parameters between the CC and GLC environments is a reflection of the species' adaptive potential, since a population can adjust the sounds emitted by its individuals to the environment's features, revealing acoustic plasticity.

Beavers are known for their gnawing performance, e.g., felling trees. Even though this is well known, the biomechanics of it are not, and so this is the focus of this study. The lower incisors work as main cutting tools so that their technical parameters were studied. There are 3 angles (adding to 90°) of importance in cutting: 1) the wedge angle, the angle of the incisor tip; 2) the clearance angle between tooth and material (tree trunk); and 3) the chip angle between incisor tip and the perpendicular to the surface of the trunk. Cutting is usually oblique to the wood fibers. For technical wood cutting tools, an optimal wedge angle of 27° is known under certain conditions, and for the incisor of Castor fiber the wedge angle was determined using micro-Computed Tomography (µCT) scans to be 26.95°. Potential cutting forces of beavers were estimated for wood chips (2 mm in thickness) of 3 sample tree species. For plum trees hardness forces ranged from 246 to 328 N, and for maples from 190 to 254 N. Finite element analyses were performed to determine stresses in the incisor under different loads on the incisor tip. Three hypotheses concerning gnawing were posed and are supported by the data: 1) The shape of the cutting blade of the incisor determines the geometry of wood chips and ultimately the maximum wood hardness that can be cut. 2) Clearance angle and maximum gape determine the maximum diameter of a tree that can be cut (if rough bark is neglected). 3) Functionally most importantly the lower incisors are optimized in shape and supporting tissue for compression stress with all forces being transmitted along the locations of the center of gravity in theoretical cross sections within the tooth, so that only compression occurs under load.

Fire is essential to maintain the open forest structure required by the southeastern fox squirrel (Sciurus niger niger). In recent decades, managers of the longleaf pine (Pinus palustris) ecosystem have transitioned from dormant-season to growing-season burns, which more effectively limit midstory hardwood encroachment. Similarly, aggressive hardwood removal programs have been employed to further reduce hardwood midstory. However, fox squirrels are dependent on oaks (Quercus spp.) for food and cover; thus, it is unclear how growingseason burns and hardwood removal may affect habitat quality for fox squirrels. We used compositional analysis to investigate selection of home ranges within the study area by 48 radiocollared fox squirrels on the Fort Bragg Military Installation, North Carolina. We used resource utilization functions with growing-season fire history and other habitat covariates as explanatory variables to test whether growing-season fires influenced the selection of habitat components within home ranges. Lastly, using a sample of fox squirrel relocations and paired random points, we performed binomial logistic regression to test whether habitat selection by fox squirrels was influenced by the availability of oaks and longleaf pines and select forest stand structural characteristics. When establishing home ranges, fox squirrels selected southern yellow pine over other cover types. Within home ranges, fox squirrel use increased with decreasing distance to a riparian area but was not affected by the application of growing-season fires. At the population level, fox squirrels selected for greater densities of reproductively mature oak stems. Fox squirrels likely benefit from growing-season fires that maintain expansive upland pine stands but are negatively affected by homogeneous fire application and mechanical hardwood removal that reduce the occurrence of reproductively mature oaks across the landscape. Managers should strive to maintain oaks in riparian areas, fire shadows, and naturally occurring patches within pine stands when managing for fox squirrels.

Gastroliths, or stones found in the digestive tract of some pinnipeds, were gathered (n = 128) from temporarily captive juvenile Steller sea lions (n = 23, Eumetopias jubatus) at the Alaska SeaLife Center and characterized by their size and mass. Blubber depth and season were significant predictors of gastrolith mass and also positively associated with larger animals. From this, we conclude that they are likely actively ingested for a functional use rather than incidental.

Trophic guilds are useful concepts for advancing our knowledge of trophic structure of communities, dynamics of species interactions, redundancy in ecosystem services, resilience to disturbances, response to climate change, conservation strategies, etc. For insectivorous bats, current literature suggests 8 trophic-related guilds. These include 3 guilds based on the openness of foraging areas, 3 based on the style of feeding, and 2 recently proposed subguilds among gleaners. Some gleaners are “passive,” using densely cluttered vegetation in which echolocation is ineffective, and others are “actively” gleaning, using echolocation to procure prey. None of these guilds is based on the actual diets of bats. We analyzed 33 reports of diet composition representing 51 species of arthropod-feeding bats inhabiting North and Central America. We wanted to determine if the classical guild structure was concordant with the actual diets of bats and to compare guild structure in the Nearctic with that in the Neotropics. Discriminant function and principle component analyses generated 5 groups of genera based on the proportion of various arthropod taxa (mainly orders) in their diets. These groups were very different from classical guilds and showed almost no overlap among bat genera between the 2 continental regions. A similar analysis based on prey flying ability and hardness of their exoskeletons suggested 4 guilds that were more consistent with classical guild concepts, had higher rates of unambiguous guild assignment, and also showed major continental differences. Our results suggest a new arrangement of 4 guilds for arthropod-feeding bats in North and Central America that are based primarily on 2 features of their prey. New molecular techniques should allow us to build on this arrangement by significantly improving the taxonomic level of prey identification.