The current distribution of the bighorn sheep in Mexico represents a reduced proportion of its original area. Previous population genetics studies conducted in Mexico have only included data from Tiburon Island in the Gulf of California and few individuals from the continent. The aim of this article was to describe aspects of the population genetics of Mexican bighorn sheep in order to aid in the management and conservation of the species. We analyzed 117 samples from the states of Sonora and Baja California Sur using 91 intersimple sequence repeat loci. Our results indicated that the Mexican samples of bighorn sheep have relatively low levels of genetic diversity (H ≈ 0.26) and low genetic differentiation (ϴ ≈ 0.07) that may be the result of the recent colonization and origin of the populations in Mexico. The individuals from Southern Baja California are genetically different from the Sonoran sample, but this genetic differentiation is low, perhaps due to the low levels of genetic variation of the Mexican populations. The results obtained in this study are relevant for population management of the bighorn sheep in Mexico in order to design translocation plans and management strategies to maintain genetic diversity and, in consequence, the health and future survival of the populations.

A large, but poorly studied, bottlenose dolphin community, Tursiops truncatus, inhabits coastal waters of Normandy (Normano-Breton Gulf, English Channel, France). In this study, the social structure and abundance of this community were assessed using photo-identification techniques. Like other bottlenose dolphin communities worldwide, this resident community has a fission—fusion social structure with fluid associations among individuals (half-weight index = 0.10). Association patterns were highly variable as indicated by a high social differentiation (S = 0.95 ±0.03). The majority of associations were casual, lasting days to months. However, individuals exhibited also a smaller proportion of long-term relationships. A mean group size of 26 was large compared with other resident coastal communities, and variable, ranging from 1 to 100, which could be the results of ecological conditions, in particular resource predictability and availability. Analyses also showed that the community was organized in 3 social clusters that were not completely isolated from each other. Abundance was estimated at 420 dolphins (95% confidence interval: 331–521), making this coastal community one of the largest identified along European coastlines. Because human activities in the Gulf are expected to increase in the upcoming years, long-term demographic monitoring of this dolphin community will be critical for its management.

Dispersal behavior in white-tailed deer (Odocoileus virginianus) predominantly occurs in 1-year-old males; however, females of the same age also disperse. The timing of female dispersal during fawning season and low dispersal rates suggest that competition for mates and reduced inbreeding are not ultimate causes of female dispersal, as suggested for males. We proposed that female dispersal is the result of competition for space when pregnant females seek to isolate themselves before and after parturition. To test this hypothesis, we conducted a meta-analysis of female dispersal rates from 12 populations of white-tailed deer and predicted dispersal rate and distance were positively related to deer density. We found a positive relationship between dispersal rate and deer per forested km² and between dispersal distance and deer per forested km². These results are consistent with the hypothesis that female dispersal is density-dependent and caused by the exclusion of subordinate 1-year-olds as adult females seek isolation before and after parturition.

The European roe deer (Capreolus capreolus) responds to environmental conditions that vary in time and space across its distributional range, generating many different space use patterns. To test the expectation that variation in movement patterns should track changes in environmental conditions, we used the net squared displacement metric to identify the factors shaping observed movement patterns of roe deer in the French Alps. Based on 5 years of data from 25 radiomonitored roe deer (54 individual-years), we found that movements were longest in spring and summer when the normalized difference vegetation index (NDVI) was higher and shortest in autumn and winter when NDVI was lower and snow cover was present. Roe deer displayed long displacements toward high elevations with gentle slope when the NDVI was higher. The higher quality food resources at higher elevations may have compensated for the energy costs of those movements. Contrary to previous studies on roe deer in mountain ranges, we showed that roe deer movements in the northern French Alps should be interpreted as within home range habitat selection (48 cases; 89%) rather than as partial migration because very few deer (6 cases; 11%) stabilized their activity in distinct home ranges across seasons.

Mammalian carnivores are affected by various anthropogenic disturbances near urban environments. Urban expansion and increased anthropogenic activity near and in preserved habitats may cause shifts in the current spatial distributions of those species. To predict the effects of future land-use changes on mammalian carnivores, we modeled their current occurrence across former Fort Ord Army Base as a function of urban proximity and road/trail density. We collected detection/nondetection data for domestic dogs, coyotes (Canis latrans), gray foxes (Urocyon cinereoargenteus), raccoons (Procyon lotor), striped skunks (Mephitis mephitis), and bobcats (Lynx rufus) using scent stations. We analyzed our data with likelihood-based occupancy modeling and used evidence ratios based on Akaike information criterion weights to infer the effect of each variable on occurrence and detection probabilities for each species. We used the estimated weighted model coefficients of the predictive variables to create current and future species distribution maps given proposed landscape changes in the study area. Domestic dogs were more likely to use areas closer to the urban edge, while gray foxes showed a preference toward inland areas. Detection probability was highest in areas closer to the urban edge for striped skunks and in areas with high road/trail densities for raccoons. Our results suggest that the distribution of domestic dogs will most likely expand with future development, while those of gray foxes will contract. We predict that future land-use changes outside of preserved areas will have an adverse effect on gray foxes within the protected areas.

The endangered Ozark big-eared bat (Corynorhinus townsendii ingens) is restricted to eastern Oklahoma and western and north-central Arkansas, where populations may be susceptible to losses of genetic variation due to patchy distribution of colonies and potentially small effective population sizes. We used mitochondrial D-loop DNA sequences and 15 nuclear microsatellite loci to determine population connectivity among Ozark big-eared bat caves. Assessment of 7 caves revealed a haplotype not detected in a previous study (2002–2003) and gene flow among colonies in eastern Oklahoma. Our data suggest genetic mixing of individuals, which may be occurring at nearby swarming sites in the autumn. Further evidence of limited gene flow between caves in Oklahoma with a cave in Arkansas highlights the importance of including samples from geographically widespread caves to fully understand gene flow in this subspecies. It appears autumn swarming sites and winter hibernacula play an important role in providing opportunities for mating; therefore, we suggest protection of these sites, maternity caves, and surrounding habitat to facilitate gene flow among populations of Ozark big-eared bats.

In long-lived temperate bats, female philopatry can influence the genetic structure of roosting groups and the potential for individuals to interact across generations. Although direct observation of dispersal between social groups is difficult given the vagility and nocturnal activity of most bats, molecular markers can be used to infer dispersal and mating patterns. Here we report on female philopatry among pallid bats, Antrozous pallidus, a species that exhibits dynamic fission—fusion roosting behavior in which philopatry and familiarity with a roosting area may help individuals choose roost sites and gain benefits associated with social roosting. In addition, we use genetic data to draw inferences about how dispersal and mating relate to the presence of divergent mitochondrial clades, which have been previously reported for pallid bats in western North America. We found significant genetic structure among colonies in central Oregon based on sequence variation at the mitochondrial (mt) DNA control region (pairwise ФФ_ST = 0.08–0.678), but very little structure among colonies for bi-parentally inherited nuclear microsatellites (pairwise F_ST = 0.004–0.01) indicative of female philopatry and male-mediated gene flow. Interestingly, some bats captured in the same colony had mtDNA haplotypes that differed by more than 12% yet failed to exhibit differences at nuclear markers. Thus, even though such divergence values are sometimes associated with species differences, evidence indicates that bats from these clades freely interbreed. This unusual pattern seems likely to be the result of postglacial range expansions from separate southern refugia northwards followed by recent secondary contact.

The skeleton is often the only remaining structure of the Guiana dolphin, Sotalia guianensis, after decomposition of carcasses. This study investigates the bone development of Guiana dolphins beached on the coastline of the state of Espírito Santo, Brazil. External measurements of 43 thoracic limbs were obtained. Internal structures (radius, ulna, and humerus) were also measured. Dual-energy X-ray absorptiometry (DXA) was used to evaluate bone mass. The variables concerning the thoracic limb were tested using the Akaike information criterion to scale the best growth model when correlated with age and by the allometric model when they were correlated with total body length. The efficacy of DXA was also tested. The Brody growth model (best fit) showed that the thoracic limb stopped growing around the age of 2, while total body length ceased to grow at the age of 5.5. The thoracic limb presented early growth (negative allometry) compared with total body length. The methodology used to measure bone mass was efficient when considering ash weight. No difference in bone density was observed between the right and the left forelimb (P > 0.05), male and female (P > 0.05), or between dolphins found in the 3 sites we monitored. The deposition of bone mass was high in the early stages of life, and stabilization occurred at around the age of 13.

Many leporid species have overlapping ranges, but ecological differences may make for profoundly different population structure in the same area. In southern Illinois, swamp rabbits (Sylvilagus aquaticus) and eastern cottontails (S. floridanus) co-exist, but swamp rabbits are habitat specialists associated with floodplain forests and eastern cottontails exhibit more general habitat preferences. Additionally, swamp rabbits exist at the northern edge of their range in southern Illinois, whereas eastern cottontails are well within the core of their range. To determine whether these differences resulted in differences in genetic structure, we assessed the population differentiation of these 2 sympatric species in southern Illinois using polymorphic microsatellite markers. We employed a combination of sampling techniques including tissue sampling from trapped rabbits and collection of fecal pellets from swamp rabbit latrine logs. Swamp rabbits appeared to be differentiated within 50 km of Illinois’ Cache River watershed (K = 4 populations) suggesting that local populations are relatively isolated, whereas eastern cottontails exhibited no discernable genetic structure (K = 1). Such a result confirms the expected relationship of greater genetic structure in a habitat specialist (i.e., swamp rabbits) versus a habitat generalist (i.e., eastern cottontails). Unlike eastern cottontails, our results suggest that swamp rabbits experience low genetic connectivity in southern Illinois likely due to restricted dispersal, linear distribution of habitat, and smaller effective population size as mediated by habitat fragmentation.

Population genetic theory indicates that a species' standing level of genetic diversity (GD) is explained in large part by the long-term effective population size (N_e). N_e depends not only on intrinsic species attributes but also on extrinsic factors such as environmental conditions that limit range sizes and promote or limit gene flow. We explored how various factors associated with N_e influence mammalian GD by first reviewing published estimates of mammal microsatellite variation and subsequently considering GD as a function of habitat type, trophic class, body size, range size, and conservation status. Our results indicate that microsatellite GD (i.e., heterozygosity and allelic diversity) is positively correlated with range size in threatened/endangered mammals although no significant effects of habitat, trophic class, or body size were observed. We also show that, on average, mammals have less GD than do birds or fishes.

In Fennoscandia, red-backed vole populations (Myodes spp.) often show regular fluctuations of abundance of 3- to 5-year periods. In contrast, only a few populations show evidence of cyclic fluctuations in North America. From 2001 to 2009, we livetrapped southern red-backed voles (Myodes gapperi) in 3 mature jack pine and 3 mature black spruce forest stands in the Muskuchii hills region, Quebec, Canada. We found that their density fluctuated (up to 41-fold) with a cyclical pattern and 4-year periods. Our study is the first to demonstrate cyclic dynamics in a southern red-backed vole population found in the boreal forest of North America. Regular pulse of food or heavy predation may be responsible for the fluctuations of southern red-backed voles. Furthermore, vole cycles may help elucidate the factors driving the irruptions of owls in the boreal forest.

Of the 3 species comprising the genus Leptonycteris Miller, L. curasoae has been the least studied with respect to its long-distance flights and potential for seasonal migrations. We studied long-distance movements between islands and between islands and the mainland in the Curaçaoan long-nosed bat. We used mark—recapture with periodic sampling and marking of bats in Aruba, Curaçao, Bonaire, and 1 location (Butare) in Falcón State, on the Venezuelan coastline. Between October 2008 and April 2014, we captured a total of 7,518 individuals at 11 sites (Aruba: n = 1,827, Curaçao: 778, Bonaire: 4,128, and Butare: 785). Between 78.3% and 98.0% of the bats captured at each island and mainland were marked, and the overall percentage of recaptured animals across all sampling sites was 8.31% (n = 529). L. curasoae inhabits the 3 islands year-round. On each island, it roosts in several caves, which can be used alternatively by the same individuals. Despite being a resident species, L. curasoae can perform long-distance oversea flights between islands and between islands and the South American mainland. A total of 11 long-distance flights were recorded (2 Bonaire—Aruba, 4 Bonaire—Curaçao, 1 Curaçao—Bonaire, 1 Bonaire—Venezuela, and 3 Aruba-Venezuela). We propose that populations of this species in Aruba, Curaçao, Bonaire, and Falcón State, Venezuela, exchange individuals, and part of the insular populations migrate seasonally southward as a response to cyclical changes in local resource availability and the yearly reproductive regime.

Pinnipeds have great potential for comparative studies of mother—pup recognition due to the contrasting maternal strategies adopted by otariids and phocids. Typically, otariid mothers perform foraging trips during lactation, leaving their pups in the colony, whereas phocid mothers remain close by their pups during the entire nursing period. Unlike most phocids, harbor seal (Phoca vitulina) females forage during the nursing period, which exacerbates the need for effective mother—pup vocal recognition in this species. Individual differences and ontogeny-related changes in airborne and underwater harbor seal mother attraction calls were investigated. Acoustic differences between aerial and underwater components of amphibious pup calls were also assessed. Sixteen acoustic parameters were measured on 1,072 calls from 88 pups recorded during the 2011–2013 breeding seasons in the St. Lawrence Estuary, Canada. Discriminant function analysis (DFA) correctly assigned 42.6% and 44.2% of airborne and underwater calls, respectively, to individual pups. A majority of highly individualized acoustic parameters were affected by pup age and body length. These results indicated that harbor seal pup calls encode an individual signature that might allow recognition of young by mothers, in which case females must continuously learn their pup's changing voice throughout of the rearing period. The fundamental frequency, total duration, and frequency-modulation slopes were constant between aerial and underwater components of amphibious calls. This could facilitate females' memorization of these highly individualized acoustic parameters to identify their offspring's call in both media.

We examined recordings from a 15-month (May 2009–July 2010) continuous acoustic data set collected from a bottom-mounted passive acoustic recorder at a sample frequency of 6 kHz off Portland, Victoria, Australia (38°33′01″S, 141°15′13″E) off southern Australia. Analysis revealed that calls from both subspecies were recorded at this site, and general additive modeling revealed that the number of calls varied significantly across seasons. Antarctic blue whales were detected more frequently from July to October 2009 and June to July 2010, corresponding to the suspected breeding season, while Australian blue whales were recorded more frequently from March to June 2010, coinciding with the feeding season. In both subspecies, the number of calls varied with time of day; Antarctic blue whale calls were more prevalent in the night to early morning, while Australian blue whale calls were detected more often from midday to early evening. Using passive acoustic monitoring, we show that each subspecies adopts different seasonal and daily call patterns which may be related to the ecological strategies of these subspecies. This study demonstrates the importance of passive acoustics in enabling us to understand and monitor subtle differences in the behavior and ecology of cryptic sympatric marine mammals.