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Conservation geneticists apply genetic theory and techniques to preserve endangered species as dynamic entities, capable of coping with environmental change and thus minimizing their risk of extinction. Snow leopards are an umbrella species of High Asia, and a keystone for maintaining biodiversity within this fragile ecosystem. A clear understanding of patterns of snow leopard genetic diversity is critical for guiding conservation initiatives that will ensure their long-term persistence. Yet, a comprehensive analysis of snow leopard genetic variation is lacking. The number of published snow leopard genetic studies is far fewer than for other imperiled big cats. Here, I review the limited genetic work to date on snow leopards and the significant knowledge gaps to be filled. An emphasis must be placed on describing and understanding population genetic dynamics within and among meta-populations to provide information about the interactions between landscapes and the micro-evolutionary processes of gene flow and genetic drift. These results can be used to evaluate the levels and dynamics of genetic and demographic connectivity. A lack of connectivity, particularly in the low density, small populations that typify snow leopards, can lead to multiple demographic and genetic consequences, including inbreeding depression, loss of adaptive potential, and heightened susceptibility to demographic and environmental stochasticity. New efforts in conservation research on snow leopards should focus on this line of inquiry, and the opportunities and challenges for that are outlined and discussed to encourage the required, and considerable, transboundary partnerships and collaborations needed to be successful.

Application of next-generation sequencing (NGS) to DNA metabarcoding can greatly increase the understanding of predator–prey dynamics and the conflict between wildlife and humans, but remains underutilized for carnivores such as the threatened snow leopard (Panthera uncia). To date, this technique was hindered by the difficulty in discerning closely related caprines (Caprinae). We identified a segment of mitochondrial cytochrome c oxidase subunit 1 (MT-CO1) to differentiate these prey, and used this marker in tandem with a portion of mitochondrial 12S rRNA (MT-RNR1) to determine dietary items in 165 genetically confirmed snow leopard scats from four range countries. Identified prey species consisted of ten medium to large mammals, three small mammals, and two birds. The dominant prey consumed varied by country, with markhor (Capra falconeri) most prevalent in Pakistan, Siberian ibex (C. sibirica) in Mongolia and Kyrgyzstan, and blue sheep (Pseudois nayaur) in China. Livestock comprised 31% of diet occurrences from Pakistan and 15% from Mongolia. Domestic livestock included goat (C. aegagrus hircus), sheep (Ovis aries), bovids (Bos taurus, B. grunniens, and potentially hybrids), and horse (Equus caballus). Protection and management of regionally specific wild prey is crucial for sustaining snow leopard populations, although overall dietary breadth suggests that snow leopards may exploit other species if necessary, including livestock. Additional sampling efforts across seasons, years, regions, and areas with varying degrees of livestock depredation are needed. MT-CO1 in conjunction with MT-RNR1 can be applied to other carnivore diet studies, making it an important tool for conservation and research, particularly in ecosystems with pastoral communities.

Patterns of spatial genetic variation can be generated by a variety of ecological processes, including individual preferences based on habitat. These ecological processes act at multiple spatial and temporal scales, generating scale-dependent effects on gene flow. In this study, we focused on bobcats (Lynx rufus), a highly mobile, generalist felid that exhibits ecological and behavioral plasticity, high abundance, and broad connectivity across much of their range. However, bobcats also show genetic differentiation along habitat breaks, a pattern typically observed in cases of isolation-by-ecology (IBE). The IBE observed in bobcats is hypothesized to occur due to habitat-biased dispersal, but it is unknown if this occurs at other habitat breaks across their range or at what spatial scale IBE becomes most apparent. Thus, we used a multiscale approach to examine isolation by ecology (IBE) patterns in bobcats (Lynx rufus) at both fine and broad spatial scales in western Texas. We genotyped 102 individuals at nine microsatellite loci and used partial redundancy analysis (pRDA) to test if a suite of landscape variables influenced genetic variation in bobcats. Bobcats exhibited a latitudinal cline in population structure with a spatial signature of male-biased dispersal, and no clear barriers to gene flow. Our pRDA tests revealed high genetic similarity in similar habitats, and results differed by spatial scale. At the fine spatial scale, herbaceous rangeland was an important influence on gene flow whereas mixed rangeland and agriculture were significant at the broad spatial scale. Taken together, our results suggests that complex interactions between spatial-use behavior and landscape heterogeneity can create non-random gene flow in highly mobile species like bobcats. Furthermore, our results add to the growing body of data highlighting the importance of multiscale study designs when assessing spatial genetic structure.

Snow leopards (Panthera uncia) are an enigmatic, high-altitude species whose challenging habitat, low population densities and patchy distribution have presented challenges for scientists studying its biology, population structure, and genetics. Molecular scatology brings a new hope for conservation efforts by providing valuable insights about snow leopards, including their distribution, population densities, connectivity, habitat use, and population structure for assigning conservation units. However, traditional amplification of microsatellites from non-invasive sources of DNA are accompanied by significant genotyping errors due to low DNA yield and poor quality. These errors can lead to incorrect inferences in the number of individuals and estimates of genetic diversity. Next generation technologies have revolutionized the depth of information we can get from a species’ genome. Here we used double digest restriction-site associated DNA sequencing (ddRAD-seq), a well-established technique for studying non-model organisms, to develop a reference sequence library for snow leopards using blood samples from five Mongolian individuals. Our final data set reveals 4504 loci with a median size range of 221 bp. We identified 697 SNPs and low nucleotide diversity (0.00032) within these loci. However, the probability that two random individuals will share identical genotypes is about 10−168. We developed probes for DNA capture using this sequence library which can now be used for genotyping individuals from scat samples. Genetic data from ddRAD-seq will be invaluable for conducting population and landscape scale studies that can inform snow leopard conservation strategies.

Significant knowledge gaps persist on snow leopard demography and reproductive behavior. From a GPS-collared population in Mongolia, we estimated the timing of mating, parturition and independence. Based on three mother–cub pairs, we describe the separation phase of the cub from its mother as it gains independence. Snow leopards mated from January–March and gave birth from April–June. Cubs remained with their mother until their second winter (20–22 months of age) when cubs started showing movements away from their mother for days at a time. This initiation of independence appeared to coincide with their mother mating with the territorial male. Two female cubs remained in their mothers’ territory for several months after initial separation, whereas the male cub quickly dispersed. By comparing the relationship between body size and age of independence across 11 solitary, medium-to-large felid species, it was clear that snow leopards have a delayed timing of separation compared to other species. We suggest this may be related to their mating behavior and the difficulty of the habitat and prey capture for juvenile snow leopards. Our results, while limited, provide empirical estimates for understanding snow leopard ecology and for parameterizing population models.

Aim: We explore the phylogeography of Himalayan wolves using multiple genetic markers applied on a landscape‐scale dataset and relate our findings to the biogeographic history of the region. Location: Himalayas of Nepal, the Tibetan Plateau of China and mountain ranges of Central Asia. Taxon: Himalayan wolf (also called the Tibetan wolf), Canis lupus chanco. Methods: We present a large‐scale, non‐invasive study of Himalayan wolves from across their estimated range. We analysed 280 wolf scat samples from western China, Kyrgyzstan and Tajikistan at two mtDNA loci, 17 microsatellite loci, four non‐synonymous SNPs in three nuclear genes related to the hypoxia pathway, and ZF genes on both sex chromosomes. Results: Our results corroborate previous studies showing that the Himalayan wolf forms a distinct lineage adapted to high altitudes in excess of 4,000 m elevation. We found a correlation between hypoxia adaptation and the divergent Himalayan wolf mtDNA haplotype found across the Tibetan Plateau of Qinghai, the Tibetan Autonomous Region and the Nepalese Himalayas. We identified a region of admixture between Himalayan and grey wolves at the boundary of their distributions, where the Tibetan Plateau elevation gradually drops. Main Conclusion: Based on multiple genetic markers, the Himalayan wolf forms a reciprocally monophyletic lineage with a unique adaptation to high altitude. We propose that the divergence of the lineage is related to past uplift of the region, and that the lineage maintains its high‐altitude niche, in part, by means of its genetic adaptation to hypoxia. We conclude that the Himalayan wolf merits taxonomic recognition and designation as an evolutionary significant unit (ESU).

Subspecies designations within temperate species’ ranges often reflect populations that were isolated by past continental glaciation, and glacial vicariance is believed to be a primary mechanism behind the diversification of several subspecies of North American cervids. We used genetics and the fossil record to study the phylogeography of three moose subspecies (Alces alces andersoni, A. a. gigas, and A. a. shirasi) in western North America. We sequenced the complete mitochondrial genome (16,341 base pairs; n = 60 moose) and genotyped 13 nuclear microsatellites (n = 253) to evaluate genetic variation among moose samples. We also reviewed the fossil record for detections of all North American cervids to comparatively assess the evidence for the existence of a southern refugial population of moose corresponding to A. a. shirasi during the last glacial maximum of the Pleistocene. Analysis of mtDNA molecular variance did not support distinct clades of moose corresponding to currently recognized subspecies, and mitogenomic haplotype phylogenies did not consistently distinguish individuals according to subspecies groupings. Analysis of population structure using microsatellite loci showed support for two to five clusters of moose, including the consistent distinction of a southern group of moose within the range of A. a. shirasi. We hypothesize that these microsatellite results reflect recent, not deep, divergence and may be confounded by a significant effect of geographic distance on gene flow across the region. Review of the fossil record showed no evidence of moose south of the Wisconsin ice age glaciers ≥ 15,000 years ago. We encourage the integration of our results with complementary analyses of phenotype data, such as morphometrics, originally used to delineate moose subspecies, for further evaluation of subspecies designations for North American moose.

Selection forces that favor different phenotypes in different environments can change frequencies of genes between populations along environmental clines. Clines are also compatible with balancing forces, such as negative frequency-dependent selection (NFDS), which maintains phenotypic polymorphisms within populations. For example, NFDS is hypothesized to maintain partial migration, a dimorphic behavioral trait prominent in species where only a fraction of the population seasonally migrates. Overall, NFDS is believed to be a common phenomenon in nature, yet, a scarcity of studies were published linking naturally occurring allelic variation with bimodal or multimodal phenotypes and balancing selection. We applied a Pool-seq approach and detected selection on alleles associated with environmental variables along a North-South gradient in western North American caribou, a species displaying partially migratory behavior. On 51 loci, we found a signature of balancing selection, which could be related to NFDS and ultimately the maintenance of the phenotypic polymorphisms known within these populations. Yet, remarkably, we detected directional selection on a locus when our sample was divided in two behaviorally distinctive groups regardless of geographic provenance (a subset of GPS-collared migratory or sedentary individuals), indicating that, within populations, phenotypically homogeneous groups were genetically distinctive. Loci under selection were linked to functional genes involved in oxidative stress response, body development and taste perception. Overall, results indicated genetic differentiation along an environmental gradient of caribou populations, which we found characterized by genes potentially undergoing balancing selection. We suggest that the underlining balancing force, NFDS plays a strong role within populations harboring multiple haplotypes and phenotypes, as it is the norm in animals, plants and humans too. This article is protected by copyright. All rights reserved.

Rapid warming in High Asia is threatening its unique ecosystem and endemic species, especially the endangered snow leopard ( Panthera uncia ). Snow leopards inhabit the alpine zone between snow line and tree line, which contracts and expands greatly during glacier-interglacial cycles. Here we assess impacts of climate change on global snow leopard habitat from the last glacial maximum (LGM; 21 kyr ago) to the late 21st century. Based on occurrence records of snow leopards collected across all snow leopard range countries from 1983 to 2015, we built a snow leopard habitat model using the maximum entropy algorithm (MaxEnt 3.3.3k). Then we projected this model into LGM, mid-Holocene and 2070. Analysis of snow leopard habitat map from LGM to 2070 indicates that three large patches of stable habitat have persisted from the LGM to present in the Altai, Qilian, and Tian Shan-Pamir-Hindu Kush-Karakoram mountain ranges, and are projected to persist through the late 21st century. These climatically suitable areas account for about 35% of the snow leopard's current extent, are large enough to support viable populations, and should function as refugia for snow leopards to survive through both cold and warm periods. Existence of these refugia is largely due to the unique mountain environment in High Asia, which maintains a relatively constant arid or semi-arid climate. However, habitat loss leading to fragmentation in the Himalaya and Hengduan Mountains, as well as increasing human activities, will present conservation challenges for snow leopards and other sympatric species.

The snow leopard (Panthera uncia) is an apex predator on the Tibetan Plateau and in the surrounding mountain ranges. It is listed as Vulnerable in the IUCN's Red List. The large home range and low population densities of this species mandate range-wide conservation prioritization. Two efforts for range-wide snow leopard conservation planning have been conducted based on expert opinion, but both were constrained by limited knowledge and the difficulty of evaluating complex processes, such as connectivity across large landscapes. Here, we compile >6000 snow leopard occurrence records from across its range and corresponding environmental covariates to build a model of global snow leopard habitat suitability. Using spatial prioritization tools, we identified seven large continuous habitat patches as global snow leopard Landscape Conservation Units (LCUs). Each LCU faces differing threat levels from poaching, anthropogenic development, and climate change. We identified ten potential inter-LCU linkages, and centrality analysis indicated that Tianshan-Pamir-Hindu Kush-Karakorum, Altai, and the linkage between them play a critical role in maintaining the global snow leopard habitat connectivity. However, international border fences, railways and major roads can fragment LCUs and potentially obstruct linkages. We propose LCU-specific conservation strategies and transboundary cooperation that should be highlighted in future snow leopard conservation. This effort represents the first range-wide, systematic landscape conservation plan for snow leopards, and provides a rigorous and analytically sound basis for further survey and evaluation.

Delineating conservation units is a fundamental step in recovery planning for endangered species. Yet, challenges remain in the application and validation of scientifically evaluated conservation units in management practice. The Canadian government makes use of Designatable Units (DUs) as the primary conservation unit under their Species‐at‐Risk Act. DUs must be ecologically discrete and have demonstrated evolutionary significance, which, in the case of woodland caribou (Rangifer tarandus caribou), has led to the definition of multiple DUs across Canada. Simultaneously, Environment and Climate Change Canada has released two recovery strategies affecting four DUs, wherein DUs are subdivided into smaller conservation units. However, the two recovery strategies adopt different definitions for the conservation unit. For the Boreal DU, the Local Population is considered the conservation unit for recovery management, whereas for Southern Mountain DU, the conservation unit for recovery is the subpopulation, which may or may not be comprised of several Local Populations. The scientific rationale for the difference between recovery strategies is unclear, not necessarily supported by genetic or demographic evidence, and highlights a policy challenge facing caribou conservation. We argue that the current emphasis on protecting subpopulations within a DU might be inconsistent and unviable for recovery planning. Instead, the recognition and emphasis on maintaining meta‐population dynamics within DUs is essential and currently underutilized in the long‐term recovery of woodland caribou in Canada.

Climate-driven range fluctuations during the Pleistocene have continuously reshaped species distribution leading to populations of contrasting genetic diversity. Contemporary climate change is similarly influencing species distribution and population structure, with important consequences for patterns of genetic diversity and species' evolutionary potential. Yet few studies assess the impacts of global climatic changes on intraspecific genetic variation. Here, combining analyses of molecular data with time series of predicted species distributions and a model of diffusion through time over the past 21 kyr, we unravel caribou response to past and future climate changes across its entire Holarctic distribution. We found that genetic diversity is geographically structured with two main caribou lineages, one originating from and confined to Northeastern America, the other originating from Euro-Beringia but also currently distributed in western North America. Regions that remained climatically stable over the past 21 kyr maintained a high genetic diversity and are also predicted to experience higher climatic stability under future climate change scenarios. Our interdisciplinary approach, combining genetic data and spatial analyses of climatic stability (applicable to virtually any taxon), represents a significant advance in inferring how climate shapes genetic diversity and impacts genetic structure., Financial support was provided by partners of Caribou Ungava, that is, ArcticNet, Natural Sciences and Engineering Research Council of Canada (NSERC), Hydro-Québec, Xstrata Nickel-Mine Raglan, Fédération des Pourvoiries du Québec, CircumArctic Rangifer Monitoring and Assessment Network, Ministère des Resources Naturelles et de la Faune du Québec, Labrador and Newfoundland Wildlife Division, First Air, Makivik Corporation, Fédération Québécoise des Chasseurs et Pêcheurs, Fondation de la Faune du Québec, Institute for Environmental Monitoring and Research, Canada Foundation for Innovation, Petroleum Technology Alliance of Canada, Canadian Association of Petroleum Producers and Norwegian Research Council. K.M. acknowledges support from the National Science Foundation IGERT program, the National Fish and Wildlife Foundation, and Alaska EPSCoR NSF award #EPS-0701898 and the state of Alaska.

Ecosystem fragmentation and habitat loss have been the focus of landscape management due to restrictions on contemporary connectivity and dispersal of populations. Here, we used an individual approach to determine the drivers of genetic differentiation in caribou of the Canadian Rockies. We modelled the effects of isolation by distance, landscape resistance and predation risk and evaluated the consequences of individual migratory behaviour (seasonally migratory vs. sedentary) on gene flow in this threatened species. We applied distance‐based and reciprocal causal modelling approaches, testing alternative hypotheses on the effects of geographic, topographic, environmental and local population‐specific variables on genetic differentiation and relatedness among individuals. Overall, gene flow was restricted to neighbouring local populations, with spatial coordinates, local population size, groups and elevation explaining connectivity among individuals. Landscape resistance, geographic distances and predation risk were correlated with genetic distances, with correlations threefold higher for sedentary than for migratory caribou. As local caribou populations are increasingly isolated, our results indicate the need to address genetic connectivity, especially for populations with individuals displaying different migratory behaviours, whilst maintaining quality habitat both within and across the ranges of threatened populations.

The snow leopard’s life history, diet, and population status is poorly understood due to its remote distribution and occurrence at low densities. This information is critical for understanding population trends, important prey species, human-snow leopard conflict, causes for decline, genetic and demographic threats, and as a rigorous way of measuring the impact of conservation management strategies. Advances in molecular techniques have made it possible to study these factors through the use of noninvasive genetics, which have yet to be fully implemented in the study of snow leopards. Here, we summarize conservation genetic techniques, review genetic studies on wild snow leopards and describe noninvasive sampling of scat for genetic-based diet reconstruction and its benefits over other methods. Finally, we address the gaps in our understanding of these elusive creatures, and outline how conservation genetics can address these issues to better understand and conserve snow leopards.

Landscape ecology is a search for patterns in ecological process as well as the causes and consequences of those patterns, often at landscape scales. Conservation biology, historically, was largely focused at a species level; however, there is an increasing acknowledgment among conservation biologists on the need to account for ecosystem and landscape perspectives that form the basis of a species’ existence. As such, the fields of landscape ecology and conservation biology are increasingly linked. The natural history characteristics of large carnivores often make them prone to extinction, but also excellent ambassadors for ecosystem or landscape-level conservation interventions as keystone or umbrella species. Research into the landscape ecology of snow leopards is still in its infancy. As such, much may be learned by considering the techniques and findings of research conducted on other cat species such as leopards and cougars, as well as other large carnivores.

In Qinghai, China, on the Tibetan Plateau, is the Sanjiangyuan, or “Three Rivers Region.” As the headwaters of three of the world’s greatest rivers, it provides water to more than a billion people downstream, and at the source it includes some of the best snow leopard habitat in China. China is vital for the long-term persistence of this species across its range, yet it is plagued by the specter of anthropogenic impact, none more imminent than increasing development, mining, and hydro projects. In the Sanjiangyuan, multistakeholder efforts among NGOs, universities, governments, and pastoralists have initiated a strong baseline of scientific and conservation work for snow leopards. However, because of significant shortcomings in biological, sociological, and political action, much effort is still needed to ensure the survival of this species. We can draw on lessons from giant panda conservation to make the charismatic, and enigmatic, snow leopard China’s next conservation success.

Summary 1. Social organization and interactions among individuals are suspected to play important roles in the transmission and potential management of wildlife diseases. However, few studies have been conducted to evaluate sociality in wildlife disease transmission. We evaluated the hypothesis of socially facilitated transmission of chronic wasting disease (CWD) among adult female white-tailed deer using spatial location and genetic relatedness for 1387 female deer, and spatial locations of 1321 adult male deer harvested during 2002–2004 CWD control efforts in Wisconsin, USA. 2. Genetically related female deer were significantly clustered at distances of

Glacial cycles in the late Pleistocene played a dominant role in sculpting the evolutionary histories of many high-latitude organisms. The refugial hypothesis argues that populations retracted during glacial maxima and were isolated in separate refugia. One prediction of this hypothesis is that populations inhabiting different refugia diverged and then, during interglacial periods, rapidly expanded into deglaciated regions. The range of the gray wolf (Canis lupus) was modified by these expansion and contraction cycles in the late Pleistocene. Our analyses of variation of mitochondrial control region sequences corroborate previous microsatellite analyses supporting independent evolutionary histories for Coastal and Continental wolves in North America. Coastal wolves represent the remnants of a formerly widespread and diverse southern clade that expanded into coastal Southeast Alaska, likely in the early Holocene. In contrast, extant northern Continental populations appear to be admixed, composed of lineages independently arising from ancestors that persisted in either southern or northern (Beringia) refugia. This pattern of diversification suggests the possibility of 3 temporally independent colonizations of North America by wolves from Asia. Coastal wolves are the last vestige of a formerly widespread phylogroup that largely was extirpated in North America by humans during the last century. The independent phylogeographic history of these Coastal wolves has yet to be characterized. Their distinctiveness among North American wolf populations may warrant a reevaluation of their conservation status and management. DOI: 10.1644/09-MAMM-A-036.1.

From the Panthera, New York, NY 10018 (Weckworth); the College of Forestry and Conservation, University of Montana, Missoula, MT 59812 (Dawson); the U.S. Geological Survey, Alaska Science Center, Anchorage, AK 99508 (Talbot); and the Biology Department and Museum of Southwestern Biology, MSC03 2020, University of New Mexico Albuquerque, NM 87131-0001 (Cook).

Relatively little genetic variation has been uncovered in surveys across North American wolf populations. Pacific Northwest coastal wolves, in particular, have never been analysed. With an emphasis on coastal Alaska wolf populations, variation at 11 microsatellite loci was assessed. Coastal wolf populations were distinctive from continental wolves and high levels of diversity were found within this isolated and relatively small geographical region. Significant genetic structure within southeast Alaska relative to other populations in the Pacific Northwest, and lack of significant correlation between genetic and geographical distances suggest that differentiation of southeast Alaska wolves may be caused by barriers to gene flow, rather than isolation by distance. Morphological research also suggests that coastal wolves differ from continental populations. A series of studies of other mammals in the region also has uncovered distinctive evolutionary histories and high levels of endemism along the Pacific coast. Divergence of these coastal wolves is consistent with the unique phylogeographical history of the biota of this region and re-emphasizes the need for continued exploration of this biota to lay a framework for thoughtful management of southeast Alaska.

Elaborate plumage and complex songs of male birds are two of the best-known examples of sexually selected traits, yet the interaction between these traits is poorly understood. Theory suggests that among a suite of potential displays, animals will emphasize traits that are most conspicuous, least costly, or best signal condition and reduce display of other traits. Here we examined the relationship between song and plumage elaborations in cardueline finches, songbirds that are highly variable in plumage displays and songs, but that share a similar mating system. We statistically controlled for body mass, habitat characteristics, and phylogenetic relationships and found that across species song complexity was strongly negatively related to elaboration of plumage ornamentation. When plumage coloration was partitioned into carotenoid-based and melanin-based components, song complexity was negatively related to elaboration of male carotenoid-based coloration but unrelated to elaboration of melanin-based coloration. These observations support the idea that, for condition-dependent traits, animal species trade off trait expression in response to changes in the costs or the information content of these traits. We discuss several alternative explanations for the observed pattern.

Landscape genetics provides a framework for pinpointing environmental features that determine the important exchange of migrants among populations. These studies usually test the significance of environmental variables on gene flow, yet ignore one fundamental driver of genetic variation in small populations, effective population size, N(e). W(e) combined both approaches in evaluating genetic connectivity of a threatened ungulate, woodland caribou. We used least-cost paths to calculate matrices of resistance distance for landscape variables (preferred habitat, anthropogenic features and predation risk) and population-pairwise harmonic means of N(e), and correlated them with genetic distances, FST and D(c). Results showed that spatial configuration of preferred habitat and Ne were the two best predictors of genetic relationships. Additionally, controlling for the effect of Ne increased the strength of correlations of environmental variables with genetic distance, highlighting the significant underlying effect of Ne in modulating genetic drift and perceived spatial connectivity. We therefore have provided empirical support to emphasize preventing increased habitat loss and promoting population growth to ensure metapopulation viability.

The role of Beringia as a refugium and route for trans-continental exchange of fauna during glacial cycles of the past 2million years are well documented; less apparent is its contribution as a significant reservoir of genetic diversity. Using mitochondrial DNA sequences and 14 microsatellite loci, we investigate the phylogeographic history of caribou (Rangifer tarandus) in western North America. Patterns of genetic diversity reveal two distinct groups of caribou. Caribou classified as a Northern group, of Beringian origin, exhibited greater number and variability in mtDNA haplotypes compared to a Southern group originating from refugia south of glacial ice. Results indicate that subspecies R. t. granti of Alaska and R. t. groenlandicus of northern Canada do not constitute distinguishable units at mtDNA or microsatellites, belying their current status as separate subspecies. Additionally, the Northern Mountain ecotype of woodland caribou (presently R. t. caribou) has closer kinship to caribou classified as granti or groenlandicus. Comparisons of mtDNA and microsatellite data suggest that behavioural and ecological specialization is a more recently derived life history characteristic. Notably, microsatellite differentiation among Southern herds is significantly greater, most likely as a result of human-induced landscape fragmentation and genetic drift due to smaller population sizes. These results not only provide important insight into the evolutionary history of northern species such as caribou, but also are important indicators for managers evaluating conservation measures for this threatened species.

Chronic wasting disease (CWD) is a fatal, transmissible spongiform encephalopathy that affects free-ranging and captive North American cervids. Although the impacts of CWD on cervid survival have been documented, little is known about the disease impacts on reproduction and recruitment. We used genetic methods and harvest data (2002-04) to reconstruct parentage for a cohort of white-tailed deer (Odocoileus virginianus) fawns born in spring 2002 and evaluate the effects of CWD infection on reproduction and fawn harvest vulnerability. There was no difference between CWD-positive and CWD-negative male deer in the probability of being a parent. However, CWD-positive females were more likely to be parents than CWD-negative females. Because our results are based on harvested animals, we evaluated the hypothesis that higher parentage rates occurred because fawns with CWD-positive mothers were more vulnerable to harvest. Male fawns with CWD-positive mothers were harvested earlier (1 mo relative to their mother's date of harvest) and farther away from their mothers than male fawns with CWD-negative mothers. Male fawns with CWD-positive mothers were also harvested much earlier and farther away than female fawns from CWD-positive mothers. Most female fawns (86%) with CWD-positive mothers were harvested from the same section as their mothers, while almost half of male and female fawns with CWD-negative mothers were farther away. We conclude that preclinical stages of CWD infection do not prohibit white-tailed deer from successfully reproducing. However, apparently higher harvest vulnerability of male fawns with CWD-positive mothers suggests that CWD infection may make females less capable of providing adequate parental care to ensure the survival and recruitment of their fawns.

In North America, caribou (Rangifer tarandus) experienced diversification in separate refugia before the last glacial maximum. Geographical isolation produced the barren-ground caribou (Rangifer tarandus groenlandicus) with its distinctive migratory habits, and the woodland caribou (Rangifer tarandus caribou), which has sedentary behaviour and is now in danger of extinction. Herein we report on the phylogenetics, population structure, and migratory habits of caribou in the Canadian Rockies, utilizing molecular and spatial data for 223 individuals. Mitochondrial DNA analyses show the occurrence of two highly diverged lineages; the Beringian-Eurasian and North American lineages, while microsatellite data reveal that present-day Rockies' caribou populations have resulted from interbreeding between these diverged lineages. An ice-free corridor at the end of the last glaciation likely allowed, for the first time, for barren-ground caribou to migrate from the North and overlap with woodland caribou expanding from the South. The lack of correlation between nuclear and mitochondrial data may indicate that different environmental forces, which might also include human-caused habitat loss and fragmentation, are currently reshaping the population structure of this postglacial hybrid swarm. Furthermore, spatial ecological data show evidence of pronounced migratory behaviour within the study area, and suggest that the probability of being migratory may be higher in individual caribou carrying a Beringian-Eurasian haplotype which is mainly associated with the barren-ground subspecies. Overall, our analyses reveal an intriguing example of postglacial mixing of diverged lineages. In a landscape that is changing due to climatic and human-mediated factors, an understanding of these dynamics, both past and present, is essential for management and conservation of these populations.

Predicting the spread of wildlife disease is critical for identifying populations at risk, targeting surveillance and designing proactive management programmes. We used a landscape genetics approach to identify landscape features that influenced gene flow and the distribution of chronic wasting disease (CWD) in Wisconsin white-tailed deer. CWD prevalence was negatively correlated with genetic differentiation of study area deer from deer in the area of disease origin (core-area). Genetic differentiation was greatest, and CWD prevalence lowest, in areas separated from the core-area by the Wisconsin River, indicating that this river reduced deer gene flow and probably disease spread. Features of the landscape that influence host dispersal and spatial patterns of disease can be identified based on host spatial genetic structure. Landscape genetics may be used to predict high-risk populations based on their genetic connection to infected populations and to target disease surveillance, control and preventative activities.

Relatively little genetic variation has been uncovered in surveys across North American wolf populations. Pacific Northwest coastal wolves, in particular, have never been analysed. With an emphasis on coastal Alaska wolf populations, variation at 11 microsatellite loci was assessed. Coastal wolf populations were distinctive from continental wolves and high levels of diversity were found within this isolated and relatively small geographical region. Significant genetic structure within southeast Alaska relative to other populations in the Pacific Northwest, and lack of significant correlation between genetic and geographical distances suggest that differentiation of southeast Alaska wolves may be caused by barriers to gene flow, rather than isolation by distance. Morphological research also suggests that coastal wolves differ from continental populations. A series of studies of other mammals in the region also has uncovered distinctive evolutionary histories and high levels of endemism along the Pacific coast. Divergence of these coastal wolves is consistent with the unique phylogeographical history of the biota of this region and re-emphasizes the need for continued exploration of this biota to lay a framework for thoughtful management of southeast Alaska.