A 2007 survey of small mammals on Mt. Mantalingahan (2,086 m elevation), southern Palawan Island, Philippines, obtained specimens of a distinctive, previously unknown shrew (Soricidae). We describe these specimens as representing a new, monotypic genus and species, Palawanosorex muscorum. The new species was common on Mt. Mantalingahan from 1,550 to 1,950 m (near the peak) but was not detected from 700 to 1,300 m elevation. The previously known native, syntopic shrew, Crocidura palawanensis, has a slender body, slender fore and hind feet, and a long, thin tail with a few long bristles. In contrast, the new species has a stout body, broad fore feet, long claws, and a short tail covered by short, dense fur but no bristles. The dental formula traditionally used would result in assignment of the new species to Suncus, but several distinctive external and cranial features are present, and phylogenetic analyses of thousands of ultraconserved elements suggest P. muscorum is sister to most other Crocidurinae, a clade represented throughout Southeast Asia but numerically dominated by African species. The new species is a distant relative of Suncus murinus (the type species of Suncus) and all other known Southeast Asian species, including the only other shrew known to occur on Palawan (Crocidura batakorum). A time-calibrated phylogenetic analysis estimates divergence between Palawanosorex and its closest known relatives at approximately 10 Ma.

Quantifying reproductive parameters is essential for developing effective conservation plans for species of concern; however, studying reproduction in wild settings can be challenging and local data are frequently unavailable. The fisher (Pekania pennanti) is an elusive forest-dwelling carnivore of conservation concern that occurs across much of boreal North America and reaches the southernmost limit of its distribution in the southern Sierra Nevada (SSN) in California. Data on fisher reproduction in this region are limited and applicability of parameters from other areas is uncertain. To clarify how fisher populations in the SSN compare with those elsewhere in North America, we conducted a comprehensive review of available literature on reproduction throughout the species' range in North America. We then compared findings from the review with data we collected during 7 years in the SSN, focusing on the proportion of females reproducing, litter size, and the parturition date. On average across the fisher's range, the proportion of adult females that reproduced was 0.71 (range: 0.40–1.00; n = 16 studies), litter size was 2.5 (range: 1–4; n = 16 studies), and parturition occurred on 25 March (range: 3 March–17 April; n = 16 studies). In our study area, we tracked 42 adult female fishers, 35 of which reproduced and used 257 reproductive dens (74 natal, 175 maternal, 8 early failures); 0.86 of our females attempted denning (range: 0.79–1.0; n = 93 opportunities) and 0.75 were successful (range: 0.64–1.0; n = 91 opportunities monitored through the den season). Mean litter size was 1.57 (range: 1–3; n = 75 litters) and mean parturition date was 30 March (range: 17 March–12 April; n = 69 natal dens initiated). Female fishers at the southern limit of their distribution in the SSN reproduced at a rate comparable to or higher than elsewhere in North America, but average litter size was the lowest reported for the species. Female fishers in the SSN gave birth at similar or later dates than elsewhere in their range. We explore factors that might explain patterns of variation in fisher reproductive parameters and discuss conservation implications of our findings.

Bottlenose dolphins (Tursiops truncatus) and pantropical spotted dolphins (Stenella attenuata) co-occur in Golfo Dulce, a fjord-like embayment located in the southern Pacific coast of Costa Rica. We evaluated if spatial overlap by these dolphin species is associated with similar environmental requirements. Presence-only models based on niche theory were constructed by contrasting a set of spatial locations with the responses of the target species to abiotic ecogeographical variables (EGVs: depth, slope, distance to rivers, distance to 200 m isobath, mean sea surface temperature, and variation in sea surface temperature). Models were cross-validated with levels of discrimination that ranged from acceptable to excellent based on the area under the curve assessment (T. truncatus, rainy season: 0.76, dry season: 0.83; S. attenuata, rainy season: 0.84, dry season: 0.89). Both dolphin species occur in Golfo Dulce year-round; the lack of seasonality documented previously was supported by the models. Species distribution models showed no spatial overlap, with differences in EGVs affecting their distribution (T. truncatus: distance to river distance to 200 m isobath, S. attenuata: depth sea surface temperature). We argue that the coexistence of both predators in Golfo Dulce is linked to habitat heterogeneity, where critical habitats are spatially differentiated. The lack of fine-scale spatial overlap, along with influential abiotic variables, highlights a process of coexistence for dolphins that are sympatric at the scale of Golfo Dulce, but within the Gulf there is fine-scale allopatry.

Dietary specialists often reside in habitats that provide a high and predictable abundance of their primary food, which is usually difficult for other herbivores to consume because of high levels of plant toxins or structural impediments. Therefore, sympatric specialist and generalist herbivores may partition food resources within and among plants. We compared how a dietary specialist (pygmy rabbit, Brachylagus idahoensis) and generalist (mountain cottontail, Sylvilagus nuttallii) used sagebrush as a food resource during winter across 3 field sites in Idaho, United States, and in controlled feeding trials with captive rabbits. The proportion of sagebrush consumed by both rabbit species varied among sites, indicating that characteristics of sagebrush plants and the surrounding plant community influenced use of sagebrush. In addition, free-ranging and captive pygmy rabbits consumed a greater proportion of sagebrush and cropped smaller stem diameters with a greater proportion of sagebrush leaves (high monoterpenes, low fiber) relative to stems (low monoterpenes, high fiber) than did cottontails. Cottontails frequently discarded the leafy tips of sagebrush branches. Cottontails are more tolerant of fiber and less tolerant of sagebrush toxins than pygmy rabbits. Cottontails consumed large diameter stems, which diluted toxins in sagebrush but increased fiber intake and reduced digestible nitrogen intake. Pygmy rabbits are less tolerant of fiber but more able to detoxify and eliminate sagebrush toxins than cottontails. Pygmy rabbits consumed small diameter stems, which reduced fiber intake, but increased intake of toxins from sagebrush leaves. Although partitioning of stems and leaves within sagebrush plants may provide a mechanism for coexistence of specialist and generalist rabbits, higher-than-expected dietary overlap between both free-ranging and captive rabbits in winter might create resource competition in areas with high-density sympatric populations or low availability of sagebrush. In addition, these contrasting foraging strategies have the potential to influence dynamics of sagebrush communities over time.

Although herbivores rely on liver enzymes to biotransform plant secondary metabolites ingested in plant-based diets, only a few enzymes from a handful of species have been characterized at the genomic level. In this study, we examined cytochrome P450 2B (CYP2B) sequence diversity and gene copy number in a conifer specialist, the red tree vole (Arborimus longicaudus). We fed captive individuals exclusively Douglas-fir (Pseudotsuga menziesii) foliage, cloned and sequenced their liver CYP2B cDNA, and estimated CYP2B gene copy number. We identified 21 unique CYP2B nucleotide sequences, and 20 unique CYP2B amino acid sequences. Gene copy number of CYP2B was estimated at 7.7 copies per haploid genome. We compared red tree vole CYP2B with CYP2B sequences of a generalist, the prairie vole (Microtus ochrogaster), found in GenBank. Our study revealed that the CYP2B enzymes of red tree voles possess unique sequences compared to CYP2B enzymes of other herbivorous species. The unique combination of amino acid residues at key substrate recognition sites of CYP2B enzymes may underlie the ability of the red tree vole to specialize on a highly toxic diet of Douglas-fir.

Resource pulses can generate cross-habitat dispersal of consumers, and therefore affect organisms even in areas where the resource pulses do not occur. We investigated this phenomenon at the elevational treeline in the Carpathian Mountains, where beech (Fagus sylvatica) masting caused an increase in abundance of forest rodents and intensified their use of alpine meadows. We tested 3 hypotheses concerning the impact of forest rodent spillover on the abundance of meadow-dwelling pine voles (Microtus subterraneus): 1) the competition hypothesis: if the spillover affects pine voles mostly through intensified competitive interactions, then pine voles should decline when forest rodents reach their peak abundance, i.e., 1 year after masting; 2) the apparent competition hypothesis: if predators switch to alternative prey when populations of forest rodents collapse, then pine voles should decline 2 years after masting; and 3) the apparent mutualism hypothesis: if the increase of forest rodents temporarily releases pine voles from predatory pressure, pine voles should increase in synchrony with forest rodents—1 year after masting. Our results, while correlative in nature, supported the apparent mutualism hypothesis: 1 year after masting, both forest rodents and pine voles strongly increased their abundance. Two years after masting, when populations of forest rodents crashed, abundance of pine voles returned to pre-masting levels rather than collapse. These findings suggest that pulsed spillover, known mostly from negative effects on organisms in recipient habitats, can also create indirect positive interactions. Furthermore, they illustrate how density-dependent spillover of animals might increase the spatial scale of masting effects beyond the habitats where seeds are released.

Most measures of predation risk have evaluated the baseline of risk according to habitat structure, when supplemental food availability was constant. Fewer studies have analyzed the effect of a predator's presence or abundance, and those studies have usually been conducted under controlled conditions or using scats, urines, or odors. We tested if apprehension in collared peccaries (Dicotyles angulatus) was affected not just by habitat structure but also by level of resource availability, and presence of top predators (puma [Puma concolor] and jaguar [Panthera onca]) in the immediate area. We classified microhabitats with different levels of risk based on vegetation structure, and compared apprehension of peccaries in shrubland, edge, and forest with sparse understory. To evaluate perceived predation risk, we used giving up densities (GUDs) in 3 trials with different food quantity. We related daily GUDs to predator presence, according to pictures recorded on trail cameras located around the experimental sites. The shrubland microhabitat was classified as the most dangerous, where peccaries were most fearful, while the edge and the forest interior were considered safer. Visibility was the habitat structure variable that most explained the levels of apprehension. Results from trials on days with the greatest numbers of predator photos were more similar among microhabitats, and peccaries left higher GUDs on the days when predators were photographed in the area. Food availability had a minor influence on GUDs. Sites and microhabitats that favor ambush cover are more risky for prey. Predator presence in the area modified temporally the perception of predation risk in prey, which expressed more apprehension and foraged less in the area at those times.

We name and describe a new species of long-tailed sigmodontine rodent of the genus Tanyuromys, based on 3 specimens collected from 3 different localities in northern Ecuador, during the period 1953–2008. All 3 localities are at middle elevations on the Pacific Andean slopes and specimens were taken both in intact and disturbed forest areas. Tanyuromys previously has been treated as including a single species—T. aphrastus (Harris, 1932); however, using morphological and molecular characters (mitochondrial cytochrome b [Cytb], 1,143 bp), we herein recognize 2 species: T. aphrastus proper, which, so far as known, occurs only in Costa Rica and Panama, and a new species known only from Ecuador. The Ecuadoran species, like T. aphrastus, is characterized by a long tail (ca. 1.5 × length of head plus body); large, complexly constructed, pentalophodont molars; braincase with beaded supraorbital margins continuous with raised temporal ridges; short, anteriorly constricted incisive foramina; short, narrow palatines; and small auditory bullae. Although similar morphologically, which explains why the 2 species have hitherto been regarded as 1, the few specimens available of each differ in that the new species has, among other traits, a narrower interorbital breadth, narrower zygomatic plate, invariably (thus far) distinct supraorbital bead continuing posteriorly over parietal to lambdoidal crests as a prominent raised ridge, relatively large lateral wing of the parietal, skull with more angular rather than more rounded contours. Molecular and morphological characters confirm that specimens of T. aphrastus from Costa Rica and Panama are quite similar; they differ in Cytb sequences by 1.2%. The new species from Ecuador, in contrast, differs from the Central American T. aphrastus in Cytb sequences by 10.2%. The 2 species form a well-supported clade; we infer the genus' phylogenetic associations within the Oryzomyini, based on the complete Cytb sequence.

The subgenus Phyllodia (genus Pteronotus) comprises 9 species ranging from the western coast of Mexico to central Brazil, including Greater and Lesser Antilles. Two of them, Pteronotus rubiginosus and Pteronotus sp. 1, form an endemic South American clade within Phyllodia and are reported in sympatry for several localities in Guyana, Suriname, French Guiana, and northern Brazil. We herein performed a comprehensive investigation to fully characterize the cranial variation and genetic intraspecific structuring within this clade. We also integrated genetic, morphological, and acoustic evidence to formally describe the species previously reported as Pteronotus sp. 1. Specimens of P. rubiginosus occurring in sympatry with the new species have a more distinctive cranial phenotype than those from allopatric areas, suggesting character displacement as a potential force promoting divergence by decreasing resource competition or reproductive interactions between them. Although the 2 species are sympatric in several localities, the divergence in their echolocation calls also may be promoting resource partitioning at the microhabitat level, with P. rubiginosus foraging in less cluttered areas and the new species restricted to more cluttered areas.

Townsend's big-eared bat (Corynorhinus townsendii townsendii) is a wide-ranging subspecies found throughout the western United States. Of the 5 subspecies currently recognized within C. townsendii, 2 are federally endangered and 2 others are considered species of concern. In California, C. t. townsendii is a species of concern given its loss of habitat and presumed limited dispersal capabilities. Here, we investigated the genetic structure and diversity of a group of maternity colonies across the Inyo-White Mountains in west-central California. Analysis of both nuclear (microsatellite loci) and mitochondrial (D-loop fragment) data show a lack of structure across the study region and significant isolation-by-distance, supporting gene flow among maternity colonies in a stepping stone pattern. The maternity colonies in our sampling region are thus part of 1 genetically healthy, panmictic population. Despite the overall genetic viability of C. t. townsendii in this region, we suggest maintaining the connection between colonies is a crucial step in the management and persistence of the subspecies.

El murciélago orejón de Townsend (Corynorhinus townsendiii townsendii) es una subespecie de amplia distribución encontrada en todo el oeste de los Estados Unidos. De las 5 subespecies de C. townsendii reconocidas actualmente, 2 son consideradas federalmente en peligro de extinción y 2 otras son consideradas como especies de interés para la conservación. En California, C. t. townsendii es una especie de interés para la conservación por la pérdida de su hábitat y capacidad de dispersión limitada. Este estudio investiga la estructura genética y la diversidad de un grupo de colonias maternas a través de las Montañas Inyo y White en el oeste-central de California. Análisis de los datos nucleares (loci de microsatélites) y mitocondriales (fragmento D-loop) muestran una ausencia de estructura a través de la región de estudio y un importante aislamiento por distancia que suportan el flujo genético entre colonias maternas por un modelo de escalón. En consecuencia, las colonias maternas en nuestra región de estudio son parte de 1 población genéticamente saludable y panmíctica. A pesar de la viabilidad genética de C. t. townsendii en esta región, sugerimos que conservar la conexión entre colonias es un paso importante en la conservación y persistencia de la subespecie.

Arthropods are the primary dietary constituents of species of the genus Myotis. The genus comprises 3 ecomorphotypes of polyphyletic origin, each associated with a different foraging strategy: aerial, trawling, and gleaning, related to the subgenera Selysius, Leuconoe, and Myotis, respectively. We explored the extent to which differences in diet characterized these ecomorphotypes. Based on a broad review of the literature, we classified the diet of species of Myotis based on hardness and vagility of consumed prey. A significant negative relationship was found between the percent volume consumption of hard and soft arthropods and between the aerodynamic characteristics of fast- and slow-flying prey. A cluster analysis yielded 3 groups of Myotis species based on their diet: 1) those for which hard prey represent more than 80% of the volume of excreta; 2) those for which hard prey represent 45% to 80% of the volume of excreta; and 3) those for which hard prey represent less than 45% of the volume of excreta. These 3 groups are related to bat size and consistent with the recognition of 3 ecomorphotypes. Nonetheless, some species may display flexibility in diet composition depending on food availability. More specifically, larger species that consume hard prey also consume soft prey, whereas smaller bats may be unable to consume hard prey because of biomechanical limitations. Regardless of their phylogenetic lineages, latitudinal distribution, or biogeographic affinity, species of Myotis of similar size and morphology consume arthropods with similar characteristics.

Bats have been portrayed as important consumers of mosquitoes, but evidence supporting this claim is surprisingly scant. We collected the fecal material of 2 common North American bats at 22 sites in Wisconsin, United States and screened samples for mosquitoes using a recently improved molecular method for detecting arthropod DNA. Overall, we detected 17 discrete operational taxonomic units assigned to the mosquito family (Diptera: Culicidae), 15 of which were assigned at the species level. We detected mosquitoes in 71.9% of samples and at all sampling sites for little brown bats (Myotis lucifugus). By comparison, we detected mosquitoes in 33.3% of samples and one-half of the sampling sites for big brown bats (Eptesicus fuscus). Our results suggest that the incidence and taxonomic richness of mosquito prey consumed by bats is considerably higher than has been previously shown. In light of globally declining bat populations, we propose that future studies reassess the importance of trophic interactions between bats and mosquitoes.

A common yet largely untested assumption in the theory of animal movements is that increased rates and a wider range of movements, such as occurs during breeding, make animals more vulnerable to mortality. We examined mortality among 34 white-tailed deer (Odocoileus virginianus) wearing GPS collars during the autumn breeding season of 2006 and 2007 in a heavily hunted, forest-agricultural landscape of central New York state. We evaluated whether individuals having higher rates of movement incurred higher rates of mortality and whether mortality risk was higher when deer were in less familiar areas. We used a Cox proportional hazards model to analyze how mortality risk changes with movement rates measured over 3 time periods: < 1 day, up to 2 weeks prior to death, and 3–4 weeks prior to death. Overall, deer increased their movement rates as autumn progressed, males more so than females. However, deer that died moved at a slower rate relative to surviving deer up to 2 weeks prior to death (β = -2.22 ± 0.81; 95% confidence interval [CI] = -3.91 to -0.51) and a slower rate on their day of death compared to deer that survived (β = -1.77 ± 0.73; 95% CI = -3.19 to -0.33). Site familiarity was not significantly related to mortality risk. Deer were equally likely to die within their 50% core use area as elsewhere within their autumn home range. We hypothesize that increased sociality associated with breeding may make animals more vulnerable to harvest mortality. Our findings contradict general assumptions about the influences of movement behavior on mortality risk, suggesting that patterns may be sensitive to the spatiotemporal context of the movement analysis.

Habitat fragmentation can alter many ecological processes, including animal movement and habitat-use patterns. Understanding how habitat fragmentation influences movement and habitat use is critical for predicting longterm consequences of the negative impacts of disturbances. Fires in Joshua Tree National Park in the Mojave Desert were historically rare disturbances but have become increasingly common, generating novel patterns of habitat heterogeneity. We examined the effects of post-fire spatial complexity of burned lands on spring and daily movement distances of Merriam's kangaroo rat, Dipodomys merriami, in Joshua Tree National Park. Movement distances did not show a direct relationship with the amount of post-fire remnant vegetation; rather, we found that D. merriami increased spring movement distances within the patchily burned sites, which also showed the lowest small mammal abundances. However, in burned sites, D. merriami maintained larger territories than in the unburned site. The adaptability of D. merriami to fragmentation could be an asset for restoration via seed dispersal within burned sites in the Mojave Desert.

The foraging patterns and behaviors of predators can be discerned using GPS data. We used GPS data to investigate the temporal patterns of wolverine (Gulo gulo luscus) foraging on large prey in northern Alberta. We built a predictive model of wolverine large-prey events (beaver predation or ungulate scavenging) based on the spatial and temporal patterns of wolverine GPS data at foraging sites we visited in the field in winter. We used this model to predict large-prey events throughout our entire wolverine GPS dataset in winter and summer. We then evaluated how variables related to prey availability, seasonality, competition, and territoriality affected wolverine encounter time, residency time, and return time at predicted large-prey events. We found that wolverines encountered large prey more often in the spring when there is increased beaver and ungulate availability. The total time that wolverines spent at large-prey events was greater in winter (3.11 days [95th percentile = 2.62–3.63 days]) than summer (2.08 days [95th percentile = 1.70–2.51 days]), potentially because prey availability is limited in winter or prey is easier to capture in summer. Wolverines partitioned the total time at events into multiple visits, reducing their residency time and increasing their return time with each revisit, indicating biomass decline through time. The time between visits in winter (10.12 days [95th percentile = 7.99–12.56 days]) and summer (8.39 days [95th percentile = 7.18–9.74 days]) suggests wolverines might be patrolling their home range. We also found that wolverine residency time decreased and return time increased when there were other large-prey events available. Moreover, wolverine residency time at events increased when other wolverines were in the area. Our results suggest that large-prey events are important to the energy balance of wolverines and that wolverine foraging behavior is dynamic in response to environmental change.

Movement patterns can influence an animal's ability to secure food, find mates, and avoid enemies, potentially affecting individual fitness. We studied movement patterns of 10 male and 3 female endangered Florida panthers (Puma concolor coryi) using location data collected from a long-term (2005–2012) GPS collar study. Males traveled faster and covered longer daily distances than females during both the wet and dry seasons (wet:dry—males 289:372 m/h and 4,616:6,701 m; females 186:280 m/h and 2,629:5,239 m). Panthers occupying higherselected habitat traveled faster, but with shorter daily movement distances in comparison to habitats that were less frequently selected. An index of risk (derived using traffic volume and road density) that was linked to habitat predicted to be avoided by panthers was associated with reduced daily movement distances. Our results suggest that Florida panthers alter their movement patterns in response to environmental change and anthropogenic disturbances.

Describing predation patterns and especially estimating kill and consumption rates is essential for understanding the functional responses of predators. An understanding of the carrying capacity of the landscape, based on prey availability, also helps to formulate recovery plans for persecuted species. We studied the feeding behavior of the Persian leopard (Panthera pardus saxicolor) in Tandoureh National Park (355 km²) in northeastern Iran, near the Turkmenistan border. Between September 2014 and May 2017, we collared and monitored 6 adult leopards (5 males and 1 female) using GPS-satellite Iridium collars. We investigated 310 clusters of fixes as likely to be kill sites. In total, 130 kills were identified to species, suggesting a mean kill rate of approximately 3.3 ± 0.3 (SE) kills/month per adult male leopard, which is higher than reported by most previous studies. The leopards varied considerably in the time they spent outside the national park; only 1 individual appeared to subsist mainly by raiding livestock. The availability of medium-sized ungulates at adequate densities is likely to be important for future leopard conservation efforts. The management of problem individuals also may promote coexistence of humans and leopards, even in prey-rich areas.

Persistence of top predators in protected areas requires healthy populations of prey species. Jaguars (Panthera onca) are top predators in the Caatinga dry forest, a xeric domain in northeastern Brazil. Poaching is a threat to populations of jaguar prey in the Caatinga, but it is still widely popular among locals. Here, we investigated molecularly identified jaguar scats to assess prey composition in a protected area where large prey has been heavily depleted or driven extinct by poaching. We also make direct comparisons between trophic niche width and mean prey size through a literature review. We show that over 90% of the diet of jaguars was comprised of prey under 5 kg, mainly armadillos. Furthermore, we found that the values of trophic niche width (2.21) and mean prey size (5.23 kg) in our study area are among the lowest ever described for jaguars in the literature. Our results demonstrated that jaguars are able to shift their diet to small prey when larger quarry is scarce. However, subsisting in such a stressful trophic position may lead to decreased levels of recruitment and low emigration rate. Breeding females would have difficulty raising cubs without abundant large prey. If jaguars are to persist in the Caatinga, effective actions to reduce poaching inside protected areas and corridors must be implemented. One of the most important jaguar populations in this domain inhabits our study site, and prey conservation is paramount for long-term persistence of this top predator in the Caatinga.

The raccoon dog (Nyctereutes procyonoides viverrinus) has recently become common in urban environments in Japan. We predicted that, like other carnivores adapted to urban environments, raccoon dogs in urban areas should have smaller home ranges than those in rural areas. We investigated the size of home ranges of raccoon dogs in the Akasaka Imperial Grounds, a 51-ha green area in central Tokyo. Between August 2012 and August 2014, 7 adult males and 4 adult females were radiotracked. Mean (± SD) home range size of these 11 raccoon dogs (100% minimum convex polygon = 17.6 ± 13.0 ha; 95% fixed kernel = 8.3 ± 5.7 ha) was smaller than that of raccoon dogs in rural areas obtained in previous studies, and core areas (75% local convex hull) averaged 3.7 ± 4.1 (SD) ha. We detected no seasonal changes in home range size. These results were consistent with the notion that urban carnivores typically have small home ranges. The small home range size seems to be explained by abundance of food resources, restricted environment, and the high population density of raccoon dogs in the urban green area.