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While studying the systematics and taxonomy of round-eared sengis (genus Macroscelides), we identified an unusual specimen from remote northwestern Namibia in the collection of the California Academy of Sciences. To determine if this represented a different species, we made 9 collecting trips with 5,616 trap-nights of effort that produced 16 voucher specimens (including the original specimen) of the unusual sengi. These specimens are distinguished from other Macroscelides species by morphological metrics (they are smaller), external features (rusty-tinged pelage, large subcaudal gland, and lack of dark skin pigment), and by divergence at 3 independently segregating DNA loci. These traits are the basis for the description of a new species of Macroscelides that seems to be confined to gravel plains associated with the distinctive reddish colored Etendeka geological formation of northwestern Namibia. The new species appears to be reproductively isolated from congeners, because portions of its distribution are sympatric with that of the Namib round-eared sengi (M. flavicaudatus), and we found no evidence of hybrid individuals or gene flow. The new species is allopatric with the Karoo round-eared sengi (M. proboscideus), which is found about 500 km to the south. The new species, along with M. flavicaudatus, is endemic to Namibia. With this 3rd species in the genus, there are now 19 recognized extant species in the order Macroscelidea.
The diversity of fossorial moles in East and Southeast Asia is contained in the 2 species-rich genera Mogera (8 species) and Euroscaptor (8 or more species), and the 3 monospecific genera Scapanulus, Scaptochirus, and Parascaptor. To better understand the evolution and biogeography of these fossorial moles, we conducted molecular phylogenetic analyses using mitochondrial cytochrome-b (Cytb; 1,140 base pairs [bp]) and 12S rRNA (approximately 830 bp) and nuclear recombination activating gene 1 (Rag1; 1,010 bp) gene sequences from 5 species of Euroscaptor, 6 of Mogera, and the single species of Scaptochirus. Phylogenetic estimates revealed 5 distinct lineages of East and Southeast Asian fossorial moles: Mogera, Scaptochirus, Euroscaptor mizura, E. parvidens, and E. malayana–E. klossi–E. longirostris. Our results support the monophyly of Mogera but not Euroscaptor, indicating a need for taxonomic revision of the latter genus. We hypothesize that Mogera originated in the central portion of its range and then dispersed to peripheral islands, such as Taiwan and the Japanese Islands. The fragmented distribution of Southeast Asian Euroscaptor presumably arose from habitat competition (invasion) from Mogera species, long-range dispersal, vicariance events, or a combination of these, explaining the high species richness of fossorial moles in this region.
Across North America, anthropogenically induced habitat fragmentation has led to a severe decline in populations of black-tailed prairie dogs (Cynomys ludovicianus). Although the area occupied by black-tailed prairie dogs in Chihuahua, northwestern Mexico, also has recently declined, this site remains comparatively unaffected by human disturbance. Cytochrome-b sequences and 10 nuclear microsatellite loci were analyzed across 13 colonies to test if due to large size, absence of plague, and protected status, the black-tailed prairie dogs from Janos possess relatively high levels of genetic variation and low genetic structure; or if recent population decline and peripheral effects result in relatively low genetic variation and high genetic structure. Analysis suggests moderate mitochondrial genetic variation relative to other sciurids, and not significantly different nuclear genetic variation relative to other populations of prairie dogs. Furthermore, in accordance to black-tailed prairie dog social organization, genetic structure among local populations was significant, and within-colony variation was higher than among-colony variation for both markers. FST was higher for mitochondrial than for nuclear DNA related to female philopatry and male-biased gene flow. Finally, a negative correlation between genetic differentiation as a function of colony area and population size found for nuclear microsatellite loci suggests an increased effect of genetic drift in smaller and less-dense colonies because of recent habitat fragmentation. In conclusion, despite being a peripheral and declining population, Janos black-tailed prairie dogs retained genetic variation that has been maintained by their social structure and dispersal pattern.
En Norte América, la fragmentación del hábitat inducida por el hombre ha provocado una reducción considerable de las poblaciones de perros llaneros de cola negra (Cynomys ludovicianus). Aunque el área ocupada por las colonias de perros llaneros en Chihuahua, al noroeste de México, también se ha reducido recientemente, esta población ha sido menos afectada por la perturbación humana. Se analizaron secuencias del citocromo b (Cytb) y 10 microsatélites nucleares en 13 colonias para poner a prueba si la población de perros llaneros de cola negra de Janos posee niveles de variación genética relativamente altos y baja estructura genética debido a su gran tamaño, ausencia de peste y estatus de protección; o si la disminución poblacional reciente y los efectos periféricos han resultado en la presencia de baja variación y alta estructura genética. Los análisis sugieren que la variación genética mitocondrial es moderada con relación a otros sciúridos y que la variación genética nuclear no es significativamente distinta en relación a otras poblaciones de perros llaneros. Además, de acuerdo con la organización social de los perros llaneros de cola negra, la estructura genética entre poblaciones locales fue significativa y la variación hacia el interior de las colonias fue mayor que entre las colonias para ambos marcadores. Con relación a la filopatría de las hembras y la dispersión sesgada hacia los machos, la FST fue mayor para el ADN mitocondrial que para el ADN nuclear. Finalmente, para los marcadores nucleares se encontró una correlación negativa entre la diferenciación genética y el área de la colonia y el tamaño poblacional, lo que sugiere un incremento en el efecto de la deriva génica en las colonias más pequeñas y menos densas como resultado de la fragmentación del hábitat reciente. En conclusión, la estructura social y el patrón de dispersión ha mantenido la variación genética de los perros llaneros de cola negra de Janos a pesar de considerarse una población periférica y en declive.
Many seed-hoarding species are faced with ephemeral pulses of seeds that result in competition at seed sources and the need to minimize hoarding time during the limited time seeds are available. Here we tested the hypothesis that a seed-hoarding species (Père David's rock squirrel [Sciurotamias davidianus]) rapidly scatter hoards seeds near seed sources to maximize harvest rate, and then subsequently recaches seeds to further reduce cache losses. We tracked the caches of wild walnut (Juglans mandshurica) scatter hoarded by S. davidianus, the exclusive dispersal agent of this highly preferred nut species. We followed dispersed nuts in both the field and in a large enclosure in a manner that allowed us to follow patterns of recaching through the scatter-hoarding process. In the field, S. davidianus initially cached close to nut sources and then subsequently recached nuts on multiple occasions progressively farther from sources, always in the same direction, at lower densities, and at sites with more vegetative cover (e.g., under shrubs). In enclosures, each of 6 squirrels first cached nuts closer to the nut source on the 1st day of observation, and then subsequently recached nuts closer to the nest, sometimes at decreasing densities. We suggest that, in addition to pilferage risk, cache spacing by S. davidianus may be influenced by the potential for competition at the seed source and proximity to the burrow or the core of the home range, and that caches might be managed to accommodate all of these factors. Future studies should consider how such recaching behavior influences patterns of cache recovery, the ultimate distribution of dispersed nuts, and seed fates.
I evaluated the effects of age and experience raising young on behaviors associated with defending maternal territories in primiparous yearling, primiparous adult, and multiparous adult Belding's ground squirrels (Urocitellus beldingi). Intensities of vigilant and aggressive behavior were lowest among primiparous yearlings, intermediate among primiparous adults, and highest among multiparous adults, with differences being greatest during gestation and lactation and declining after the 1st emergence of young from the natal burrow. These differences suggest that both age and experience raising young improve territorial behaviors in this species. I also evaluated responses of female U. beldingi to a nonthreatening (caged) conspecific intruder placed in the maternal territory. Investigation of the intruder and aggression directed at the intruder were relatively low among multiparous females throughout the reproductive period, suggesting that these females were able to discern that the intruder did not pose a threat. Among primiparous adults, investigatory and aggressive responses toward the intruder were high during gestation but declined thereafter, suggesting that as the reproductive period progressed these females were better able to discriminate between a threatening and a nonthreatening stimulus. Among primiparous yearlings, investigatory and aggressive behaviors were low during gestation, and females spent about 30% of the duration of tests watching the intruder without overt vigilance. Investigatory and aggressive behaviors increased during lactation and declined to low levels after emergence of young from the natal burrow, suggesting that after an initial hesitancy to respond to the intruder, primiparous yearlings reacted to the intruder as a threat, but by the end of the reproductive period may have been able to determine that the caged intruder was not threatening. Overall, results of this study are consistent with the idea that both age and experience raising young influence maternal territorial behaviors and discrimination abilities in female U. beldingi.
Little is known about the specific dietary preferences of many marsupials. We undertook digestion studies in 2 species of insectivorous marsupials, the stripe-faced dunnart (Sminthopsis macroura) and the fat-tailed dunnart (Sminthopsis crassicaudata), because these are 2 species that are regularly kept in captivity, although nothing is known about their nutritional requirements in the wild. Morphology and dimensions of the gastrointestinal tract of both species also were assessed. The test diets included 2 laboratory-type diets: cat formulation and Wombaroo small carnivore mix; and natural insect diets: adult crickets (Acheta domesticus), Australian wood cockroaches (Panesthia australis), and mealworm larvae (Tenebrio molitor). Composition of the test diets on a dry-matter basis varied considerably; ranges included gross energy 16–27 kJ/g, crude protein 38–64%, lipids 9–51%, calcium (Ca) 340–17,800 mg/kg, and phosphorus 6,600–16,000 mg/kg. Depending on the diet, the digestible energy intake ranged from 359 to 816 kJ kg−−0.75 day−1 for stripe-faced dunnarts and digestible energy intake ranged from 542 to 990 kJ kg−0.75 day−1 for fat-tailed dunnarts. No single diet was appropriate if fed alone, notably the insect diets, which required Ca supplementation. The morphology of the gastrointestinal tracts of both species was simple and consisted of a unilocular stomach and relatively uniform intestine. The morphometrics of the gastrointestinal tracts of fat-tailed dunnarts were proportionally larger than for stripe-faced dunnarts. Fat-tailed dunnarts also needed to consume more nutrients per unit of body mass for maintenance in captivity compared to stripe-faced dunnarts.
Effective restoration of threatened or endangered species requires understanding of basic ecological requirements such as habitat selection and home range needs. The endangered riparian brush rabbit (Sylvilagus bachmani riparius) occupies areas of dense, brushy cover along streamside communities in the San Joaquin Valley of California, but over 93% of this habitat has been lost to urban and agricultural development. We released over 325 captive-born rabbits at the San Joaquin River National Wildlife Refuge (Refuge) between July 2002 and July 2005, and we monitored 312 of these rabbits via radiotelemetry to assess spatial and habitat selection. Home ranges and core areas were similar among males and females, and were larger in the breeding season than during the nonbreeding season. Perhaps reflecting a growing population, home range estimates decreased in size over the duration of the study. Animals moved in response to a wildfire in July 2004, but home range area was similar in 90-day pre- and postfire periods. Of 1,143 possible dyads, 534 (47%) exhibited a mean of 86% overlap in 95% fixed-kernel home ranges. Overlap did not differ by dyad type (e.g., male–male), but was greater in nonbreeding than in breeding seasons; unlike home ranges, we did not detect any temporal changes in overlap as might be expected in a growing population. Riparian brush rabbits exhibit scale-independent habitat selection, disproportionately favoring thick understory cover such as sandbar willow mixed with dense shrubs (blackberry, roses). Refuge managers have promoted escape cover and flood refugia at strategic locations throughout the Refuge; our results concur that these are important habitat elements in the niche of riparian brush rabbits.
Snowshoe hares (Lepus americanus) are generally sedentary, but are likely to move among habitats frequently to gain access to spatially segregated food and cover. We investigated movement patterns of hares from 2 characteristic boreal habitats using very-high-frequency radio collars (n = 300) monitored weekly and global positioning system (GPS) collars (n = 18) programmed to record locations at 30–120-min intervals. We used collar recoveries (n = 203) to estimate distance from capture to mortality site. Approximately 90% of collars were recovered within 1 km of their deployment locations, the greatest distances being recorded in winter. We used locations of GPS-collared hares to estimate seasonal home range sizes, habitat use, and diel patterns of movement among and within habitats. Seasonal home ranges were 3–6 ha in size, depending on season and habitat. Hares used multiple habitat types on a daily basis. Movement rates, based on animal locations recorded every 2 h, varied 4-fold between peak and nadir. The majority of movements between habitat types coincided with times when hares were most active. Our findings show that hares may use multiple vegetation types even when food and cover are apparently abundant in a single habitat. Hares move between these areas on a daily basis, probably to make use of better foraging opportunities in one location and return to resting sites in dense cover in a different location.
Movement and activity patterns are important components of life history, being central to resource acquisition and defense, mating behavior, and individual survival and fitness. Here, we present results from the 1st systematic radiotracking study of the masked palm civet (Paguma larvata), a widespread viverrid found in subtropical and tropical forests of Asia. From June 2004 to November 2007, we radiotracked 12 masked palm civets (5 males and 7 females) in central-south China. Mean individual home-range size based on 95% minimum convex polygons was 192.6 ha ± 42.6 SE (range = 64–451 ha). Although males had larger mean home-range sizes than females (276.8 and 136.5 ha, respectively), these differences were not statistically significant. Males also exhibited greater daily movement distances and extents than females, but we found no evidence of sexual dimorphism in body size. Masked palm civets were predominantly nocturnal, but were active intermittently during the day. No significant seasonal (monthly) differences in daily activity patterns were apparent. We did, however, observe reduced hours of activity—but not continuous inactivity—during winter; consequently, we concluded that our study animals did not hibernate or semihibernate. We speculate that our observations of home-range overlap among individuals may indicate group living in the masked palm civet.
Badgers (Carnivora, Mustelidae) constitute a nonmonophyletic assemblage of mammals that are characterized by a general similarity of appearance and a broad geographic distribution. A comparative analysis of the forelimb osteology of badgers was performed to assess how observed differences in their scratch-digging behavior are related to variation of forelimb structure. We measured forelimb bone proportions of 87 skeletal specimens and calculated 8 functional indexes that were analyzed using analysis of variance and principal component analysis to identify the osteological correlates of fossorial ability in this clade. The indexes that best characterize forelimb specialization for scratch-digging in badgers are related to a robust humerus, large humeral epicondyles, and a long olecranon process, and these features increase from digger to semifossorial forms. A large scapular area for muscle attachment and a robust ulna also are correlated with fossorial ability. Semifossorial forms are indicated to have greater forelimb muscle mass, increased mechanical advantage of the elbow extensors, and the ability of the elbow extensor and carpal and digital flexor muscles to apply high out-force to the substrate. Digger forms are indicated to have relatively less robust and longer distal limb bones, and lower limb out-force capability. This study reveals that for badgers there is a distinct relationship between the proportions of the forelimb bones and fossorial ability. The indexes tested that relate to mechanical advantage of the elbow extensors and mass and force production capacity of the musculature have the discriminatory ability to distinguish between degrees of forelimb specialization and fossorial ability of badgers.
Hibernation is an adaptive strategy to avoid harsh environmental conditions and seasonal limitations in food and water. Unlike most hibernators, grizzly bears (Ursus arctos) are aroused easily while in dens and disturbances while denning can result in fitness costs if bears become active during this period. Our objectives were to determine den selection of male and female grizzly bears at multiple spatial scales in the boreal forest and Rocky Mountains of Alberta, Canada. Grizzly bears in Alberta are designated as threatened. However, little is known about den selection by grizzly bears in the boreal forest and the current land and forest management plans do not include any mitigation measures to minimize possible impacts on the denning habitat of grizzly bears. We compared dens to random available locations within fall home ranges using geographic information system–derived anthropogenic, land cover, landscape, and food resource variables. Male and female grizzly bears had similar habitat requirements when selecting dens, and females did not avoid sites associated with a greater probability of encountering males. At the broadest scale investigated, grizzly bears avoided wetlands, and selected high-elevation, dry conifer stands with abundant high-quality spring food. At more localized scales, grizzly bears selected areas of low road densities and dense conifers associated with little high-quality autumn food. Slope angle had the most influence on den selection followed by percent autumn food, road densities, percent wetland, and percent spring food. We recommend limiting human disturbance, including open roads, within core grizzly bear conservation areas for areas with high suitable den habitat.
Only scanty and outdated knowledge is available on the food habits of the Apennine brown bear (Ursus arctos marsicanus) population, despite its critical conservation status. Based on 2,359 scats, collected from June 2006 through December 2009, we documented seasonal and annual variation in the diet of this bear population within its 1,294-km2 core distribution in Abruzzo, Lazio, and Molise National Park and its external buffer area in central Italy. Using correction factors to estimate digestible energy, we revealed substantial consumption of plant matter by bears, including herbaceous vegetation in spring (mean ± SD; 31.7% ± 25%) and early summer (19.0% ± 7%), a variety of naturally occurring berries in summer (56.5% ± 14%), and hard mast (66.9% ± 21%), largely supplemented by fleshy fruits (26.3% ± 18%), in the fall. Bears also consumed insects, mostly ants, in early summer (38.3% ± 7%), and wild ungulates in spring (10.2% ± 11%). Hard mast production strongly influenced year-to-year variation in the diet. High-quality foods, such as berries and other fleshy fruits, were increasingly consumed by bears in years of low to null hard mast productivity, suggesting that habitat productivity is currently high and diversified enough to allow bears to avoid the risk of nutritional stress during occasional hard mast failures. Nevertheless, as exemplified by a negative trend in late-summer consumption of buckthorn (Rhamnus spp.) berries by bears, our findings demonstrate the need to implement management strategies that will ensure long-term habitat productivity and provide optimal foraging opportunities for Apennine brown bears.
Molecular approaches, such as polymerase chain reaction (PCR), allow biologists to analyze the diet of mammals in more detail than conventional techniques, by targeting DNA of prey found within feces. Diets of the Antillean ghost-faced bat (Mormoops blainvillei) and sooty mustached bat (Pteronotus quadridens) on Puerto Rico were determined via PCR, and resulting sequences of DNA were compared with those in the Barcode of Life Data Systems (BOLD). We identified 21 species consumed by M. blainvillei and 4 by P. quadridens, although an additional 12 sequences were identified to genus or family. Seven taxa in the diet of these bats were of agricultural or human-health concern. All sequences, including those that did not match a reference insect in BOLD, were collapsed into molecular operational taxonomic units (MOTUs) and used to demonstrate that dietary breadth (Levin's measure) of M. blainvillei was 18% less than that of P. quadridens and that dietary overlap (Schoener's index) between species was only 11.6% at the level of species. Use of MOTUs showed significantly greater differences in dietary breadth and less dietary overlap between these insular endemics than previous analyses based on standard fecal analysis to the level of order.
Las técnicas moleculares, tales como el PCR (reacción en cadena de la polimerasa), permiten analizar el régimen alimentario de los mamíferos con un nivel de detalle que sobrepasa las técnicas convencionales. Esto se logra identificando en la excreta el ADN de las presas del mamífero. Utilizamos las secuencias de ADN encontradas en la excreta de los murciélagos barbicacho (Mormoops blainvillei) y bigotudo menor (Pteronotus quadridens) en Puerto Rico para determinar el régimen alimentario de los mismos. Ambas especies son endémicas de las Antillas Mayores. Las secuencias de ADN fueron comparadas con aquellas en el “Barcode of Life Data Systems” (BOLD). Identificamos 21 especies de insectos consumidos por M. blainvillei y 4 por P. quadridens, y 12 secuencias adicionales fueron identificadas a nivel de género o familia. Siete taxones identificados en el régimen alimentario de estos murciélagos son de importancia agrícola o para la salud humana. Todas las secuencias, incluyendo las que no coincidieron con ninguna referencia en BOLD, fueron convertidas en unidades operacionales de taxonomía molecular (MOTUs) y utilizadas para demostrar que la amplitud alimentaria (métrica Levin) de M. blainvillei es 18% menor que la de P. quadridens. El solapamiento alimentario (indice Schoener) entras las 2 especies de murciélago fue de 11.6%. El uso de MOTUs reveló diferencias significativamente mayores en amplitud alimentaria y menores en el solapamiento de dieta entre estas especies, al compararlo con análisis previos basados en análisis fecales estándares a nivel de Orden.
Wildlife managers are challenged to manage spatially structured populations efficiently and effectively, therefore dispersal and gene flow are vital to understand and manage, particularly for a harvested species. We used a genetic approach to describe the metapopulation structure of Rocky Mountain elk (Cervus elaphus) in Idaho to assess past patterns of population distribution and influences of harvest. We used elk tissue and DNA samples (n = 216) to examine genetic dissimilarity between 7 regions and 9 elk management zones throughout Idaho using microsatellite loci (n = 11). Using 5 approaches, including pairwise FST-values, assignment tests, and a Bayesian model–based clustering of genotypes, we examined the distribution of genetic variation. The distribution of genetic variation between elk populations indicated low levels of genetic differentiation among regions (expected heterozygosity [HE] = 0.55–0.61, overall FST = 0.011) and elk management zones (HE = 0.54–0.60, overall FST = 0.017). Assignment tests and migration rates indicated directional gene flow between elk populations. A patchy metapopulation best describes the distribution of genetic variation among Idaho elk populations because likely enough individual interchange occurs between geographically separated populations. The elk populations we sampled could be part of a geographically larger patchy metapopulation potentially stretching from Yellowstone National Park through Idaho into western Canada. Because of historical translocations of elk from Yellowstone National Park, insufficient time may have passed to detect differences in genetic variation. Subtle differences in the distribution of genetic variation were observed in 2 of the 9 elk management zones within 2 different regions of the state. Our findings indicate management of Idaho elk populations and dispersal are maintaining sufficient gene flow. Metapopulation structure of a harvested species based on the distribution of genetic variation is an indicator of potential genetic consequences of harvesting and sustainable harvest levels.
Desert rodents exhibit irruptive (boom–bust) population dynamics in response to pulses of primary productivity. Such unpredictable population dynamics are a challenge for monitoring population trends and managing populations, particularly for species in decline. We studied the population dynamics and occurrence of populations of the vulnerable plains mouse, Pseudomys australis (42-g body mass), during the low (bust) phase of the cycle in the Simpson Desert, Australia, to examine the use of refuges by the species and the predation pressure experienced from native and introduced predators. Specifically we investigated landscape-scale occurrence; body mass, reproduction, and population size; and presence of native and introduced predators. Our results demonstrate that P. australis contracted to discrete areas of the landscape (refuges) during the low phase and that these areas occupied a small proportion (∼17%) of the range occupied during population peaks. Animals in refuge populations had comparable body mass, occurred at similar densities to populations during the boom phase, and continued to reproduce during dry conditions. Such refuges represented a significant concentration of biomass to predators in a resource-poor environment. Native predators were rare during the low phase, suggesting that refuges naturally experienced low predation levels. Two introduced predators, feral house cats and red foxes, persisted during the low phase and exploited refuge populations of P. australis, thus representing a significant threat to population persistence. We advocate a novel approach to management of rodents in arid systems that involves identifying the discrete parts of the landscape that function as drought refuges and then focusing threat management there. The relatively small size of these refuges increases the likelihood of cost-effective management.
Large-scale variation in mammalian body size has often been found to be related to environmental conditions. A general finding among large herbivores is that body size increases with decreasing temperature (Bergmann's rule), because animals with larger body size have better heat conservation or fasting tolerance, or because higher quality forage occurs in colder environments. Using a data set on the skeletal morphology of Norwegian red deer (Artiodactyla, Cervidae: Cervus elaphus) spanning the last approximately 7,100 years, we document an inverse relationship between climatic conditions and body size. The size of Norwegian red deer, as estimated from both teeth and weight-bearing bones, was significantly larger during the warmer and wetter middle Holocene than it is today. However, the reduction in body size does not seem to be related to changing climatic conditions. Rather, this decrease happened during a period of large-scale human-mediated habitat fragmentation, increased populations of domestic herbivores, and heavy hunting pressure that reduced population density. The size of teeth was reduced as much as, or even more than, the size of weight-bearing bones, which indicates an evolutionary response rather than phenotypic plasticity to changing forage and environmental conditions. Decreased body size may be a general response in wild ungulates to a more human-dominated landscape, resulting from reduced access to optimal habitats and high adult hunting mortality.
Extreme high and low altitudes and polar environments constrain the distributional limits of terrestrial mammals. In Central Asia, vegetation on the Tibetan Plateau is limited at elevations above ∼5,500 m. Although aspects of the spatial ecology of ungulates are known across many ecosystems, logistical challenges slow the development of knowledge at the upper edge of life. We studied components of the distributional ecology of wild yaks (Bos mutus) in early winter 2012. Males and females occurred above 5,000 m, but the sexes differed socially and ecologically. On average, female groups were about 15 times larger, about 100 m higher (mean elevation 4,875 m), and in wetter or more rugged topography than males. Although females with and without young did not vary in elevation, groups with calves occurred more often in habitats with steeper slopes. An ecological surrogate and congeneric, the closely related North American bison (Bos bison), also exhibits social and ecological differentiation where males occurred historically at high elevation above tree-line habitats in the Rocky Mountains. What distinguishes the present ecology and conservation of wild yaks from bison is that opportunities persist for wide-ranging yak populations across unfenced landscapes in remote protected regions of the Tibetan Qinghai Plateau.
Investigating sources of infection for new disease cases is critical to effective disease management. Chronic wasting disease (CWD) was first detected among white-tailed deer (Odocoileus virginianus) in Illinois in 2002. Although CWD was focused in northern Illinois, 4 infected deer were sampled in 2011 from locations greater than 100 km south of the disease focus. We used assignment tests (Geneclass2 and Oncor) to determine a likely genetic source location for infected deer. Our baseline data set consisted of 310 deer sampled from 10 locations. From the baseline data set, we determined the most likely genetic source location of 15 CWD-positive and 15 CWD-negative deer. A total of 17–20% back-assigned to their sample location as their most likely genetic source location and the remainder of the animals cross-assigned to another location. The average distance between locations was 41.4 km for Geneclass2 and 43.4 km for Oncor (range 0.0–90.8 km). Distances between source and sampling locations were similar for positive and negative animals. Distances for males were greater than those for females using Oncor, but there was no difference in distance based on age. Because there are few barriers to gene flow for white-tailed deer, managers should reduce movement of deer in CWD-infected areas in an effort to reduce direct and indirect transmission of CWD.
Iriarte, A., and F. Jaksic. 2012. Los Carnivoros de Chile. Ediciones Flora y Fauna Chile y CASEB, Pontificía Universidad Católica de Chile, Santiago, Chile, 260 pp. ISBN 978-956-351-168-0, price (paper), $74.
Xiaoming Wang, Lawrence J. Flynn, and Mikael Fortelius. 2013. Fossil Mammals of Asia: Neogene Biostratigraphy and Chronology. Columbia University Press, New York, New York, 732 pp. ISBN-978-0-231-15012-5, price (hardbound), $99.50; ISBN-978-0-231-52082-9, price (e-book), $79.99.
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