Although biotic responses to contemporary climate change are spatially pervasive and often reflect synergies between climate and other ecological disturbances, the relative importance of climatic factors versus habitat extent for species persistence remains poorly understood. To address this shortcoming, we performed surveys for American pikas (Ochotona princeps) at > 910 locations in 3 geographic regions of western North America during 2014 and 2015, complementing earlier modern (1994–2013) and historical (1898–1990) surveys. We sought to compare extirpation rates and the relative importance of climatic factors versus habitat area for pikas in a mainland-versus-islands framework. In each region, we found widespread evidence of distributional loss— local extirpations, upslope retractions, and encounter of only old sign. Locally comprehensive surveys suggest extirpation of O. princeps from 5 of 9 new sites from the hydrographic Great Basin and from 11 of 29 sites in northeastern California. Although American pikas were recorded as recently as 2011 in Zion National Park and in 2012 from Cedar Breaks National Monument in Utah, O. princeps now appears extirpated from all reported localities in both park units. Multiple logistic regressions for each region suggested that both temperature-related and water-balance-related variables estimated from DAYMET strongly explained pika persistence at sites in the Great Basin and in Utah but not in the Sierra-Cascade “mainland” portion of northeastern California. Conversely, talus-habitat area did not predict American pika persistence in the Great Basin or Utah but strongly predicted persistence in the Sierra-Cascade mainland. These results not only add new areas to our understanding of long-term trend of the American pika's distribution, but also can inform decisions regarding allocation of conservation effort and management actions. Burgeoning research on species such as O. princeps has collectively demonstrated the heterogeneity and nuance with which climate can act on the distribution of mountain-dwelling mammals.

Risso's dolphins are known for the persistency of their natural markings, possibly due to the loss of pigment during the healing process of skin wounds. Nonetheless, the actual longevity and reliability of each mark type has never been assessed. In this paper, we used photographs to investigate the etiology of skin marks in the species, analyze their distribution and temporal variability, and discuss implications for photo identification. Nineteen mark types were described on the dorsal fin of Risso's dolphin, including 2 new to the literature: the snake-like mark and the protruding fat. Longevity of skin marks ranged from 6 years for the protruding fat to several decades for scrapes and dots. Persistent and reliable marks were notch, tooth-rake, and thick single and parallel scrapes. Mark change was sufficiently low that all mark types could be used for photo identification, provided that backlit or underexposed images were discarded as photographs taken under suboptimal light conditions proved to be unreliable. Finally, mark distribution and variability were unequal between age classes; juveniles were less marked and showed a higher rate of mark change than older individuals so that, even if they possessed enough notches to be classified as reliably marked, they could be confidently matched over a time interval of up to 3 years.

In Alberta, wild bison, Bison bison (Linnaeus 1758) occurring outside protected areas are assumed to have originated from the free-ranging bison populations within Wood Buffalo National Park (WBNP). As bison in WBNP are infected with 2 diseases, it was assumed that neighboring bison outside WBNP were also diseased. However, the neighboring Harper Creek and Ronald Lake bison populations have not tested positive for either disease, suggesting limited contact with WBNP herds. To resolve this, we analyzed microsatellite genotypes from all free-ranging bison groups in Alberta and one from the Northwest Territories (NWT), Canada. In the WBNP area where bison have persisted, we recover a genetically panmictic population comprising all possible subpopulations within the park, plus the adjacent Wentzel Lake herd, all of which are diseased. In contrast, but consistent with their disease-free status, we find the Ronald Lake and Harper Creek bison herds to be genetically differentiated from this larger WBNP herd, despite their close proximity. This highlights the importance of the Ronald Lake and potentially the Harper Creek herds for bison recovery. We also document the genetic impacts of translocation on the species, as the Mackenzie, NWT, and Elk Island National Park (EINP), Alberta, bison populations founded in the 1960s from WBNP animals are now genetically differentiated, but the more recently founded Hay Zama bison population is not differentiated from its source population, the EINP wood bison. Interestingly, factorial correspondence analysis, FST, and its high private allelic richness suggest that the Harper Creek population is significantly differentiated from all other bison populations studied. Though they are most closely related to WBNP populations, more study of this population is warranted.

Although the phenology of bat migration has been investigated at the population level, the timing and energy management of individual bats is poorly understood. Early arrival on the summering grounds with ample energy stores may give a fitness advantage to females preparing to raise pups. In contrast, there is no such fitness gain for males because they invest in mating during autumn. We use 3 years of capture data to investigate sex differences in spring migration passage date and body composition of Lasionycteris noctivagans. We predicted that females would arrive earlier in the spring and maintain greater fat stores than males. Females passed through the study site earlier and had more fat than males in 2 of 3 study years. Cold weather appeared to delay female migration and to deplete fat stores but did not appear to affect the passage date or fat stores of males. Our findings indicate that sex differences occur in the timing and energy management decisions of bats during spring migration. We postulate this difference in migration strategy is related to the increased demands of reproduction once females arrive at their summering grounds. Our results also suggest that females' fuel migration with energy acquired en route to a greater extent than males.

Urban expansion and associated habitat fragmentation are expected to be detrimental to global biodiversity. Natural habitat that is extensively modified often poses challenges to native fauna that must adapt to new conditions to survive. While some species decline in numbers or become locally extinct, the Eurasian red squirrel (Sciurus vulgaris) successfully inhabits cities. Because squirrels are sensitive to habitat fragmentation and their spaceuse patterns are influenced by the distribution and abundance of major food resources, their movement patterns are likely to be modified in response to changes in environmental conditions brought about by urbanization. Therefore, to investigate whether supplementary food resources are key to its success, the home ranges of squirrels inhabiting a large city park were related to both natural food sources (NFS) and anthropogenically-provided food sources (PFS) in 3 seasons. The combination of home ranges that were relatively small, year-round food availability and the lack of a seasonal body mass change indicates that the semi-urban environment can be highquality habitat. The squirrels' home ranges encompassed areas with a year-round NFS supply, but they shifted their home range core areas closer to PFS in seasons where they were more reliable, even though NFS were also abundant at the time. Additionally, heavier individuals' core areas were located closer to PFS. Consequently, our results show that human activity (i.e., via PFS) had a direct, measureable effect on squirrels' feeding habits and movement patterns even though NFS were available. However, the consequences of urbanization are not always detrimental for native animal species and an improved knowledge of energy resources and their effect on habitat use is important for understanding and minimizing the long-term impacts of humans on urban wildlife.

It is generally assumed that in unpredictable environments, the use of daily torpor and its interaction with daily activity are largely dependent on environmental thermal conditions and resource availability. Using temperature telemetry, we compared the thermal biology and activity patterns of 2 species of mulgaras (Dasycercus blythi and D. cristicauda) at 3 sites of different habitat types in central Australia. The work compared a dry period with a wet period (resource pulse). The most obvious functional difference among populations was observed in the timing of the onset of activity, which began significantly earlier in dense unburned spinifex (on average 17.7 min before sunset) than in burned spinifex (4.6 min after sunset) or on gibber plains (21.8 min after sunset). However, although the seasonal expression of torpor differed significantly between males and females, torpor use as well as seasonal timing was similar among sites and periods despite differences in rainfall and habitat. It appears that predominantly reproductive activity governed torpor depth and duration in all measured populations and both species. Our data suggest that while the timing of activity is modulated by the amount of vegetation cover and thus protection from diurnal predators, torpor expression and winter reproduction in mulgaras are functionally linked and surprisingly more or less independent of apparent resource availability. Consequently, in mulgaras, daily torpor does not seem to be employed in response to immediate energy shortage but more likely to allow reallocation of energy and nutrients towards reproduction.

The cryptic behavior of migrating bats leaves us largely uninformed of their seasonal distribution and abundance, important movement corridors, and migration behaviors. However, models of avian migration in relation to meteorological variables may prove useful in describing seasonal patterns of coastal bat activity. We pursued 2 primary objectives regarding regional autumn bat activity along the Atlantic Coast of southern New England, United States, inferred from continuous acoustic monitoring: 1) to evaluate hypotheses regarding the association of regional atmospheric conditions and coastal bat activity and 2) to construct and evaluate models that predict regional bat activity on a given night using meteorological data accessed ahead of the activity. Acoustic bat activity was attributable primarily to 2 species of migratory tree bats, red bat and silver-haired bat, but also the shortdistance migrant tricolored bat and generally sedentary big brown bat. Myotis spp. and hoary bat detections were relatively uncommon among classified calls. Coastal bat activity varied with regional wind conditions indicative of cold front passage and expected to induce a more coastal flight path, but associations with other atmospheric conditions from models of songbird migration were typically weak. Bat acoustic activity also was associated strongly with various aspects of temperature. Predictive models of regional nightly bat activity were reasonably accurate in anticipating nights of the highest and lowest bat activity, particularly for low-frequency bats such as silver-haired and big brown bat. The ability to anticipate high bat activity may help reduce adverse interactions with forthcoming wind energy development in coastal and offshore areas along the western Atlantic Ocean.

Allocation to reproduction is based on trade-offs between competing functions and available energy and nutrients. Because fruit is generally protein poor, strict frugivores may require additional protein during periods of investment in young and, in mammals, periods of milk production. Observations of frugivores supplementing their diets with protein-rich insects are accumulating and this is likely an underappreciated common strategy. However, it is unclear if protein augmentation is determined by seasonal abundances of high-protein food or by behavioral changes to navigate physiological demands. We present the 1st study asking if frugivorous bats supplement their diets with insects to obtain required energy and nutrients that could be used for successful reproduction. Using naturally occurring stable isotopes of nitrogen, we examine the roles of fruit versus insects to determine if these frugivorous mammals are truly specialists, we also ask how diet breadth varies with season, sex, and by reproductive state. We test 2 new hypotheses regarding when insect supplementation occurs using the well-studied largely frugivorous Jamaican fruit bat, Artibeus jamaicensis. The 1st hypothesis suggests protein augmentation occurs seasonally but independent of reproduction (H1). Alternatively, females may supplement their frugivorous diets with insects during the nitrogen-demanding periods of pregnancy and lactation (H2). Finally, we test a 3rd independent hypothesis (H3) that these bats are specialists, consistent with both H1 and H2. We found dietary shifts relative to season, reproductive state, and sex. The largest portion of insect use was by pregnant females. Surprisingly, lactating females did not consistently supplement their diets with insects and exhibited fruit-focused diets. Males exhibited the narrowest dietary breadth and nonreproductive females the greatest. Diet breath of all reproductive groups varied by month. Our data indicate that, while fruits remain an important part of the diet, insects may be an extremely valuable source of nitrogen to females during pregnancy.

Calomys is one of the most polytypic and widely distributed genera of the Neotropical rodent fauna. The taxonomic hierarchy for the large- and middle-sized morphotypes from the southern central Andes (SCA; C. boliviae, C. callosus, C. fecundus, and C. venustus) has fluctuated repeatedly from synonyms or subspecies to valid species. As a first approach to the taxonomic resolution of the taxa complex of this genus inhabiting the SCA, we applied an integrative quantitative assessment of currently recognized species' cranial discrimination through the analysis of geometric morphometrics. The morphometric analyses revealed the presence of 3 distinct species of Calomys in northwestern and central Argentina. We corroborated the presence of a large amount of intraspecific variation with substantial overlap for the 3 species in the morphospace. The assessment indicates that 24% of skull size variation is due to differences among species. Calomys boliviae (including C. fecundus) was the largest among the studied species, whereas the differences were subtle between C. venustus and C. callosus. The relative contribution of interspecific differences to the total skull shape variation was lower than that of size and different among the cranial views—dorsal, ventral, and lateral—analyzed (between 8% and 16%). Moreover, static allometric size changes had a major effect on skull shape differences between species. So, including ecoregions and size-free shape, variables improved significantly the amount of interspecific differentiation. We highlight the usefulness of morphometric assessments to clarify and contribute to the taxonomy of Neotropical mice.

The advent of molecular and cytogenetic methodologies has improved our ability to recognize taxonomically distinctive, but morphologically cryptic forms. However, molecular and cytogenetic data are often based on small and geographically restricted samples, often hampering an objective evaluation of alternative hypotheses such as limited and/or uneven sampling leading to character discontinuity. It is important to investigate this alternative possibility, especially when it concerns species distributed parapatrically with confusing geographical limits. In this study, we analyze patterns of qualitative and quantitative variation in cranial morphology in a series of Cerradomys samples from northeastern Brazil. These samples form a north–south transect through this region, where 2 species with parapatric distributions, C. vivoi and C. langguthi, are currently recognized. Our results show that qualitative characters regarded as diagnostic for each species vary gradually along the transect and, despite the overall similarities among samples, cranial morphometric analysis reveals an increase in size and a gradual modification of skull shape from northern to southern samples. These findings indicate that, although the distinction between C. vivoi and C. langguthi is supported by available karyological and molecular variation, these 2 species cannot be confidently distinguished based only on morphology, particularly those samples from intermediate regions of the transect. We propose an intensification of sampling in these regions, and the integrated use of cytogenetic, molecular, and morphological data, in an attempt to refine the resolution of discontinuities among population samples and to access the geographical limits between the recognized species in this genus.

Severe population declines in numerous North American bat species makes population monitoring increasingly difficult. We tested the effectiveness of an acoustic lure at increasing capture success of bats in mist nets. Increasing detection rate is especially relevant for species that have been heavily affected by white-nose syndrome, such as the Indiana bat (Myotis sodalis), little brown bat (M. lucifugus), and northern long-eared bat (M. septentrionalis). We conducted our study at 3 properties in southern Indiana during summer 2014. We set up 7 mist-netting sites at each property, netting 2 times at each site, with and without the use of an UltraSoundGate Player BL acoustic lure. The lure played recordings of various social calls from Myotis, Eptesicus, and Lasiurus spp. recorded in Europe and North America on a loop throughout the mist-net night. A total of 21 bats were caught using the lure, while 46 bats were caught without the use of the lure. We ran a series of zero-inflated Poisson generalized linear models on number of bats captured per trapping night to test whether the lure produced a difference in bat captures overall and for each genus while accounting for additional sources of variability. Using an information theoretical approach, we determined the most parsimonious models for each species grouping. For bats overall and those in the genera Myotis and Eptesicus, the top performing models contained an effect for use of the lure. This effect was positive and significant (P = 0.007) for our Myotis model, while the Eptesicus model showed a marginally significant and negative effect of the lure. We conclude that level of sociality in bat species influences the effectiveness of an acoustic lure on bat capture success. Understanding this distinction can inform when and where the use of an acoustic lure may enhance conservation goals.

Bats at northern latitudes may hibernate for up to 8 months during winter and must subsist on stored fat over this period. Environmental influences on bat emergence from hibernation are not well understood, and the degree to which bat emergence coincides with availability of their insect prey is not known. We used electronic detectors to monitor bat activity from 2001 to 2013 at a major hibernaculum, used primarily by Myotis lucifugus, in Wisconsin. We estimated dates of entry into hibernation in fall and recorded bat activity as bats emerged in spring over this 13-year period. Temperatures outside and inside the mine and airflow at the mine entrance were measured. Night-flying insects were monitored during spring from 2008 to 2013. Bat activity in spring was most strongly associated with warmer temperatures outside of the mine and was also correlated with airflow in the mine entrance. Changes in airflow were driven by temperature differentials between the mine and outside, and could serve as a signal for outside temperatures to bats inside of the mine. Insect abundance was also positively correlated with warmer outside temperatures. However, bat activity peaked before insects started to become abundant. Over the 13 years of the study, the date at which 5% of bat activity for the season was reached ranged from 10 April to 20 April, and for 50% of bat activity for the season the range was from 28 April to 4 May. The date of 5% bat activity for the season was not correlated with the date of entry into hibernation the previous fall, mean winter temperatures inside or outside of the mine, or the degree days (base 0°C) inside or outside of the mine. Our study was conducted before white-nose syndrome was documented in Wisconsin, thus our study documents hibernation behavior of healthy bats.

Fragmentation and habitat loss are top threats to tropical forest biodiversity and the Atlantic Forest is no exception. Over 80% of Atlantic Forest remnants in Brazil are < 50 ha and lack resident populations of large predators (jaguars, Panthera onca, and pumas, Puma concolor). Mesopredators with opportunistic life-history characteristics (e.g., ocelots, Leopardus pardalis) are now hypothesized to be the dominant competitor(s) in these systems and may negatively affect the spatial or temporal distribution of other sympatric mesocarnivores. We used camera-trap data, occupancy models, and temporal overlap indexes to explore whether ocelot occurrence influenced the habitat use or activity patterns of 6 mesocarnivores in reserves of the Brazilian Atlantic Forest. Ocelot occurrence did not influence the habitat use of these mesocarnivores. Moreover, the ability of some mesocarnivore species, especially the little spotted cat (L. guttulus), to adjust their activity patterns to avoid direct contact with ocelots may facilitate their coexistence in these Atlantic Forest remnants. Ocelot occurrence did not influence the activity pattern of 2 nocturnal species (the crab-eating fox, Cerdocyon thous, and the crab-eating raccoon, Procyon cancrivorus), suggesting that these species are more tolerant of ocelots than other mesocarnivores. The probability of occupancy varied among species, with tayra (Eira barbara) and South American coati (Nasua nasua) having the highest occupancy estimates; overall, occupancy by mesocarnivores correlated negatively with reserve size. Because mesocarnivores are important drivers of ecosystem function, structure, and dynamics and may occupy unique roles that cannot be filled by larger carnivores, future studies should assess environmental factors influencing the use of these small remnants of Atlantic Forest by each mesocarnivore species.

Many animals consume foods that vary in all 3 macronutrients: carbohydrates, lipid, and protein. Yet most studies of diet regulation only consider pairs of nutrients (protein and carbohydrate or protein and lipid). Diet regulation also extends beyond nutrient and energy intake to include sources of energy expenditure, such as changes in activity level. We used a right-angled mixture triangle design to quantify the 3-dimensional intake target of fat-tailed dunnarts, Sminthopsis crassicaudata, and to test the consequences of free choice for energy intake, weight gain, and activity level relative to a standard maintenance diet. Dunnarts consistently preferred a relatively high-lipid, low-protein, and low-carbohydrate diet in 3 separate feeding experiments. Dunnarts also consumed a higher total energy intake during choice relative to no-choice periods. However, the weight of dunnarts was not consistently higher at the end of choice relative to no-choice periods, which is likely because dunnarts increased their activity level during periods of choice and decreased their activity when on no-choice diets. This shows that increases in the intake of lipid, which is an important component in the diet of dunnarts, does not necessarily lead to increases in weight gain because these animals can adjust energy expenditure to balance their energy budget. These results have important implications for the design of diets for animals in captivity and demonstrate that consideration of both energy intake and expenditure are needed for a more comprehensive and integrative understanding of diet regulation by animals.

The roles of density-dependent and density-independent factors in the dynamics of tropical large herbivore populations are poorly understood. Understanding these dynamics is particularly important if the herbivore is prey for an apex predator of conservation concern because a decline in the prey could cause the predator to decline. We tested hypotheses about the roles of density-dependent and density-independent factors in the dynamics of 2 tropical ungulates, Rusa deer (Rusa timorensis) and wild pigs (Sus scrofa), in Komodo National Park, eastern Indonesia. We counted the dung of Rusa deer and wild pigs (a validated index of abundance for these 2 species) along permanently marked transects at 10 sites over 4 islands annually during 2003–2014 to estimate ungulate abundance. Ungulates were much more abundant on the 2 larger islands compared with the 2 smaller islands, with wild pig dung completely absent from the latter. During our 12-year study, Rusa deer abundance declined slightly on Nusa Kode and Rinca islands, did not change on Komodo Island, and increased on Gili Motang Island. There was a decline in abundance of wild pigs on Komodo Island and an increase on Rinca Island. Annual variation in population growth rate was strongly density-dependent and island-specific for both species, with annual rainfall and vegetation composition being relatively unimportant. Population growth rates of Rusa deer exhibited spatial synchrony, with synchrony declining with increasing intersite distance. Our findings confirm the importance of density dependence in the dynamics of tropical large herbivore populations. However, the strength of density dependence varied between species and spatially. Declines of Rusa deer and wild pigs on the larger 2 islands, which are strongholds of the Komodo dragon, are cause for concern. Continued monitoring of ungulate populations is critical for the conservation of Komodo dragon populations in Komodo National Park.

Eastern gorillas (Gorilla beringei) are among the few mammal species that seasonally consume large quantities of young bamboo shoots, which are a rich source of energy. Here, we document how the consumption of bamboo shoots coincides with changes in behavior of adult mountain gorillas (Gorilla beringei beringei) monitored by the Dian Fossey Gorilla Fund's Karisoke Research Center in Volcanoes National Park, Rwanda. We offer a preliminary analysis of possible mechanisms underlying this behavioral change by measuring energy intake rates and the presence of cyanide and alcohol—ingredients potentially associated with increased activity levels—in fresh bamboo shoots. The percentage of bamboo shoots in the diet of gorillas was correlated positively with the rate of play behavior shown by adults in 2 of the 3 study groups. Play behavior was not the result of better weather conditions and also did not reflect the availability of spare time. Rather, there is some, but not consistent, evidence for a link between energy intake rates and play behavior of adults. Cyanide was not detected in young bamboo shoots, and the presence of alcohol remains inconclusive, albeit unlikely. In sum, our results show that consumption of a high-quality food can have a direct influence on the activity budget (and by extrapolation energy expenditure) of mountain gorillas through increased rates of play behavior. However, the physiological aspects underlying this elevated activity warrant further investigation.

Reproductive performance of mammalian females depends on a broad set of extrinsic and intrinsic factors. One of the most important attributes for a female ungulate is body condition, which depends on food availability. Forage supply, in turn, is dependent on habitat quality, weather conditions, and animal density. The main objectives of our study, conducted in Augustów, Knyszyn, and Białowieża Forests in northeastern Poland from 2006 to 2011, were to quantify reproductive characteristics of female red deer (Cervus elaphus) and determine factors affecting their fertility. Targeted populations of nonmigratory deer were part of an almost natural system, which included seminatural closed forests, a multispecies ungulate guild, and large carnivores. Red deer in northeastern Poland occurred at relatively low densities and females exhibited good reproductive potential, reflected by high fertility rate, low age at 1st reproduction, and lack of reproductive senescence. Fertility was affected by age and body condition. The positive effect of body mass on female fertility declined with age, while the opposite relationship occurred with mandible fat content—its effect increased with female age. Environmental factors and population density did not affect fertility. Early survival and recruitment of young were high (73% and 52 young per 100 females, respectively). Survival of young increased with age of mother in young and prime-aged females and decreased in older females. Summer weather conditions at the time of the study were stable; therefore, their effect on female fertility was not evident. The negative effects of density dependence, which operate mainly through female body condition in this large ungulate, were weak, resulting in adequate food resources, and high fertility rates and population productivity.

Populations of large herbivores frequently display divergent migratory strategies, a likely consequence of the trade-off between the costs and benefits of migration. Globally, physical and environmental barriers disrupt migrations, leading to increased residency, which can have detrimental consequences. In the Okavango Delta, Botswana, veterinary cordon fences erected in 1982 may have caused enforced residency in some subpopulations of Cape buffalo (Syncerus caffer caffer). We used data from GPS-enabled collars fitted to females in 1 resident and 1 migratory subpopulation of buffalo to test the hypotheses that 1) residents have access to less-productive forage than migrants, 2) residents occupy smaller home ranges and live in smaller herds than migrants, 3) reproductive productivity is lower in resident herds, and 4) residents have poorer body condition than migrants. Forage characteristics varied between resident and migrant ranges, both between and within seasons. Reproductive productivity and body condition did not differ between subpopulations, but residents occupied smaller home ranges during the rainy season and lived in smaller herds than migrants. Enforced residency could have decreased carrying capacity when the fence was erected, so resident buffalo may have adapted by forming smaller herds, allowing them to maintain their body condition. The area that residents occupied was located in a more central region of the Okavango Delta than that of migrants; therefore, this area would receive higher levels of nutrients from the annual flood, which would have increased heterogeneity in resident ranges, potentially compensating for effects of disrupted migrations. These results highlight the importance of conserving landscapes with spatially and temporally heterogeneous resources to buffer effects of anthropogenic activities such as artificial barriers on migrations.

Many declining populations of the imperiled Allegheny woodrat (Neotoma magister) function as nonequilibrium metapopulations in which rates of subpopulation extirpation exceed recolonization. Quantifying and maximizing survival rates thus becomes critical for the conservation of these spatially structured populations. We used encounter histories of individually marked woodrats from subpopulations in Indiana, monitored annually from 2005 to 2013, to 1) estimate apparent annual survival rates while accounting for imperfect detection, 2) evaluate differences in apparent survival between unaugmented subpopulations and subpopulations reestablished or restored through translocation efforts, and 3) describe the effect of genetic diversity on survival. From Cormack–Jolly–Seber models developed in a Bayesian framework, apparent survival was greater for adults than for juveniles, greater for females than males, and there was a modest negative effect of density dependence. Although heterozygosity rates at 11 microsatellites increased among reinforced subpopulations following translocations, we observed no effect of heterozygosity on apparent survival. However, after translocations, average apparent survival was approximately 14% greater among recipient subpopulations than remnant subpopulations. This suggests that viability of recipient subpopulations was limited by low connectivity and the absence of genetic benefits conveyed by immigration or the potential for patches to be recolonized following local extinction. Under conditions of reduced connectivity, translocation among subpopulations to replicate natural gene flow may be appropriate to facilitate the long-term persistence of this and perhaps other nonequilibrium metapopulations.

Several lineages of small mammals frequently preyed upon by snakes have evolved snake-specific signals and displays that they use in an attempt to deter predation. Although detailed studies have been conducted on the form and function of these behaviors in a few key species, limited work has been done that directly compares behaviors between species, and none that we know of between species of separate lineages. Representative species displaying these behaviors exhibit broad overlap in geographic range, and they often occur in sympatry with each other, where they are preyed upon by the same local guild of snakes. Thus, there is potential for these independently evolved signals to exhibit some degree of convergence in sympatry, reinforcing each other in a fashion similar to what has been documented for aposematic mimicry complexes. Here, we provide the 1st direct quantitative comparison of anti-snake signaling behavior in sympatric small mammals from separate lineages: Dipodomys deserti (Heteromyidae) and Xerospermophilus tereticaudus (Sciuridae). Although some aspects of the displays of squirrels and kangaroo rats were similar (e.g., use of foot drumming, time spent investigating snake), others were not (e.g., willingness to approach closely, tail flagging, sand kicking, jump back displays). Although further research will be necessary to test directly the possibility of convergence, the forms of the signals are disparate enough that it is unlikely that the displays represent an example of convergent mimicry. Our results highlight the potential for further comparative work regarding the evolution of form and function of anti-snake signaling in small mammals.

The taxonomic status of the subspecies of Aselliscus stoliczkanus (Mammalia: Chiroptera: Hipposideridae) in China has yet to reach a consensus. To explore the variation and differentiation among populations of A. stoliczkanus from different regions of China, we conducted a series of bat surveys from 2012 to 2015. We performed multivariate morphological analyses using 16 external and 18 skull measurements and compared the sequence divergences of 2 mitochondrial genes (cytochrome b [Cytb] and cytochrome oxidase I [COI]). There were significant differences in external and skull measurements, particularly in the upper and lower canines, in the specimens from Guangxi compared with those from southwestern Yunnan and Guizhou. Sequence variation of the Cytb and COI genes was 11.0–13.2% and 12.4–14.0%, respectively, which represents differentiation at the species level. The samples from Guangxi were clustered with A. dongbacana from Vietnam in the phylogenetic trees based on COI sequences, and their sequence divergence was less than 3.2%. Based on the morphological and molecular results, we inferred that the samples from Guangxi were A. dongbacana, which represents a new record in China. Skull measurements of A. stoliczkanus from southwestern Yunnan exhibited significant morphological differences compared with those from Anlong County of Guizhou, and the sequence divergences of the Cytb and COI genes were 5.7–6.3% and 6.4–6.7%, respectively. Therefore, A. stoliczkanus from southwestern Yunnan and Anlong County of Guizhou might represent different subspecies. Finally, the phylogenetic analyses and minimal Cytb divergences of 0.2–0.9% indicated that specimens from southwestern and central Yunnan should be considered the same subspecies. Samples from Anlong County of Guizhou, Sichuan, and South Yunnan, with low Cytb divergences of 0.1–0.7%, represent another subspecies. A greater COI gene divergence was found between Libo and Anlong County of Guizhou; thus, the samples from Libo might represent yet another subspecies.

Historically, the taxonomic status of the bottlenose dolphins, Tursiops, has been confusing. Over 20 nominal species have been described in, or transferred to, the genus, but most them have been synonymized under T. truncatus, the type species of the genus. Here, we review the taxonomic status of Tursiops gephyreusLahille, 1908, from the southwestern Atlantic Ocean (SWA), a taxon long considered as either synonym or subspecies of T. truncatus. We examined a total of 280 bottlenose dolphin skulls, including the lectotype of T. gephyreus. We examined all specimens for morphological (14 characters) and morphometric (29 measurements) differences. Univariate and multivariate analyses were conducted to test differences between groups. Based on qualitative and quantitative analyses of skulls as well as the vertebrae number of Tursiops specimens from SWA, we recognized 2 distinct morphological forms of bottlenose dolphins in the region, consistent with treatment of 2 species under the “diagnosable version of the Phylogenetic Species Concept.” Six qualitative characters are reliable for the identification of both species in the SWA, but the shape of the nasal process of the right premaxilla alone is sufficient to separate the species. Furthermore, the total number of vertebrae is higher in T. truncatus (62–64) than in T. gephyreus (57–59). Based on these results, we propose the revalidation of T. gephyreus. Since T. gephyreus was recognized as inhabiting the estuaries and the surf zone alongside the Rio Grande do Sul in Brazil, Uruguay, and Argentina coasts, the conservation efforts must take into account that this region presents similar threats to the species.

Animals make directional movements toward resources to satisfy nutritional, reproductive, and protection needs. We evaluated resource selection by the spiny rat (Thrichomys fosteri) in a heterogeneous habitat, disentangling the relative importance of habitat structure, escape cover, food availability, and intraspecific competition. The last 2 variables were estimated directly by explicitly incorporating their spatiotemporal variation in the model. We radiotracked 15 males and 5 females for a median of 10 days per month for 17 months. Used and available resources were estimated at the home-range scale by intersecting the radiotracking locations (used) and random points (available) with resource maps that were either temporally static (measured only once; palm density and bromeliad cover) or dynamic (with temporal variation; arthropod biomass and conspecific abundance). We performed a resource selection function analysis using conditional logistic regression stratified by each individual location. Within their home ranges, spiny rats selected areas with high bromeliad cover and arthropod biomass. There was a negative interaction between conspecific abundance and arthropod biomass. We showed that resource selection by individuals takes into account multiple resources that vary in space and time. Individuals tended to select areas with high escape cover and high food availability balanced by low intraspecific competition.

The dhole (Cuon alpinus) is an endangered social canid that inhabits the forests of southern and southeastern Asia. A scarcity of field studies and inconsistent findings have led to a poor understanding of their ecology and conservation status. We compiled an ethogram of dhole behavior based on analysis of 395.35 min of video recordings. We recorded 3,394 behavioral events in 1,654 video clips lasting 10 s each. We classified behavioral events into 6 categories: Locomotion, Resting, Social Behavior, Feeding, Scent Marking, and Miscellaneous. Behavioral events associated with Locomotion were most frequent (40.95%), as was the proportion of time spent on such behaviors (41.89%). Dholes spent the least time exhibiting Miscellaneous and Scent Marking behaviors (1.45% and 2.64%, respectively), as well as the lowest frequency (0.74% and 4.01%, respectively). Although scent marking was relatively rare, we observed unique scent-marking behaviors in this study, including “hind bounce” and “hind scrub.” The time spent on different categories of behaviors differed significantly among males, females, and subadults. We also used camera traps and opportunistic observations to investigate the activity patterns of dholes in dry deciduous forest of Tadoba-Andhari Tiger Reserve in central India, where they are sympatric with other large predators including tigers (Panthera tigris) and leopards (P. pardus). Our findings suggested that dholes were primarily crepuscular. Fundamental knowledge about behavioral ecology is crucial for the conservation of any species, and our findings provide a new foundation for future behavioral research on this endangered social canid.

Comparisons of a species' modern and historic geographic distributions can yield important insights into patterns of biodiversity, including faunal responses to environmental change. Using morphological and genetic analyses of museum specimens and samples recently collected in the field, we document the historical occurrence of a population of colonial tuco-tucos (Ctenomys sociabilis) from Laguna Nahuelquir in Chubut Province, Argentina. This locality represents a significant increase in the geographic distribution of this species, which had been thought to be endemic to the Sierra de Cuyín Manzano located ∼130 km to the north in Neuquén Province. Field surveys of the Laguna Nahuelquir locality failed to reveal extant populations of C. sociabilis; although the habitat at this location is generally consistent with areas occupied by C. sociabilis in the Cuyín Manzano, the Laguna Nahuelquir site is now occupied by the Patagonian tuco-tuco, C. haigi. This apparent replacement of ctenomyid species is consistent with patterns of faunal turnover revealed by analyses of late Pleistocene–early Holocene cave deposits near the Sierra de Cuyín Manzano and supports the hypothesis that changes in local environmental conditions have contributed to the loss of C. sociabilis from these localities. Thus, comparisons of historical and modern specimens of ctenomyids provide evidence of range retractions by colonial tuco-tucos over multiple time scales and add to a growing body of evidence regarding the apparent effects of environmental change on the small mammal fauna of northern Patagonia.

The niche divergence hypothesis suggests that if a species exhibits intersexual differences in diet, selection should favor divergence in the feeding apparatus between the sexes. Recent work revealed that male and female southern sea otters (Enhydra lutris nereis) utilize different dietary resources in response to increased population density; females exhibit more specialized diets as a function of smaller home ranges, whereas males exhibit larger home ranges, potentially allowing them to expand their dietary breadths by feeding on prey items that are not found in female home ranges. These dietary differences suggest the potential for sexual dimorphism of the feeding apparatus (i.e., the skull). Here, we tested the hypothesis that male and female southern sea otters exhibit differences in craniomandibular traits directly related to biting ability. Univariate and multivariate analyses of 12 craniomandibular traits showed that size is the primary axis of skull variation, whereas only a handful of craniomandibular traits demonstrated significant shape differences between the sexes. Relative postorbital constriction breadth, masseter in-lever length, and cranial height differed significantly between the sexes. These 3 traits can increase the surface area of jaw muscle attachment sites and thus are directly linked to the mechanics of biting ability. Collectively, these morphological differences indicate that niche divergence may be an important mechanism maintaining sexual dimorphism in southern sea otters.