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An understanding of a species’ diet is required to make sound conservation and management decisions. Traditionally, morphological analyses of undigested hard parts from food items remaining in scats have been used to assess diets. More recently, molecular analyses of scats have been used to identify plant and prey species’ DNA, but no studies have compared morphological and molecular diet analyses for large, terrestrial carnivores. We used molecular tools to determine the percentage of black bear and coyote scats that contained 3 common prey species (caribou, moose, and snowshoe hares) in Newfoundland and compared the results to a traditional morphological analysis. We found that a ranking of relative prey frequencies was consistent between the 2 methods, but molecular methods tended to detect prey species in a greater percentage of scats for all prey species. However, there were individual scats in which a prey species was detected by morphological methods only, and we provide evidence that molecular methods could result in false negatives if prey DNA is not uniformly distributed throughout a scat or as a result of PCR inconsistency. We also found that the per sample cost comparison between morphological and molecular analyses was dependent upon whether or not a molecular test was needed to identify scats to the predator species, the cost of developing molecular methods, and the number of samples being processed. We recommend that controlled feeding studies be performed to validate molecular methods and investigate the utility of molecular techniques to estimate the proportions of food items consumed.

Hybridization presents a unique challenge for conservation biologists and managers. While hybridization is an important evolutionary process, hybridization is also a threat formany native species. The endangered species recovery effort for the red wolf Canis rufus is a classic system for understanding and addressing the challenges of hybridization. From 1987?1993, 63 red wolves were released from captivity in eastern North Carolina, USA, to establish a free-ranging, non-essential experimental population. By 1999, managers recognized hybridization with invasive coyotes Canis latrans was the single greatest threat to successful recovery, and an adaptive management plan was adopted with innovative approaches for managing the threat of hybridization. Here we review the application and results of the adaptive management efforts from 1993 to 2013 by comparing: (1) the numbers of wolves, coyotes, and hybrids captured, (2) the numbers of territorial social groups with presumed breeding capabilities, (3) the number of red wolf and hybrid litters documented each year and (4) the degree of coyote introgression into the wild red wolf gene pool. We documented substantial increases in the number of known red wolves and red wolf social groups from 1987–2004 followed by a plateau and slight decline by 2013.The number of red wolf litters exceeded hybrid litters each year and the proportion of hybrid litters per year averaged 21%. The genetic composition of the wild red wolf population is estimated to include < 4% coyote ancestry from recent introgression since reintroduction. We conclude that the adaptive management plan was effective at reducing the introgression of coyote genes into the red wolf population, but population recovery of red wolves will require continuation of the current management plan, or alternative approaches, for the foreseeable future. More broadly, we discuss the lessons learned from red wolf adaptive management that could assist other endangered species recovery efforts facing the challenge of minimizing hybridization.

The recently diminished caribou (Rangifer tarandus) population in insular Newfoundland, Canada, has been severely limited by predation on newborn calves. These neonates are patchily distributed on the landscape; therefore, to adequately understand predator–prey interactions, the temporal and geographic extent of the distribution of caribou calves must be identified so that current areas with calves can be differentiated from areas without calves. We used telemetry locations of 309 caribou calves and 100 adult females from 4 herds, 2008– 2010, to estimate the spatiotemporal distribution of caribou calves during the time when they were most vulnerable to predation, to evaluate the predictability of the calf resource among years, and to assess the degree of aggregation during calving. Patterns of calf distribution were predictable in time and space from year to year, with an average distributional overlap of 68% between years. The dispersion of female caribou during calving varied among herds from highly aggregated (8% and 20% of herd range) to more dispersed (50–70% of herd range). Postcalving (up to 9 weeks) distributions also varied among herds; the 2 more-dispersed herds remained sedentary, whereas both highly aggregated herds migrated away from their calving grounds at the end of June. The most-aggregated herd remained so as it migrated from its calving ground, whereas the less-aggregated herd spread out and moved in a variety of predictable directions. Dispersion and movement patterns varied with forest cover; herds with less forest cover in their range were more aggregated and migratory than herds with more forest cover.

Conservation concern for fishers (Pekania [Martes] pennanti) in the Pacific states has highlighted a need to develop cost-effective methods of monitoring reproduction in extant and reintroduced fisher populations. We evaluated the efficacy of nipple size as a predictive index of weaning success for females with known reproductive histories from 3 study areas in California. We captured and radiocollared 91 female fishers on 146 occasions between 2004 and 2011 and measured the width and height of all 4 nipples and quantified reproductive status via radiotelemetry. We classified each radiomarked female into 1 of 3 reproductive classes (nonbreeders, attempted breeders, and current breeders) based on our telemetry observations during the den season prior to capture. We used a modified random forests (RF) procedure to account for repeated measures of individual females sampled in multiple years. Our modified RF procedure correctly classified reproductive class for 130 (89%) and 131 (90%) of our 146 observations using raw and weighted vote totals, respectively. We calculated Cohen's kappa of 0.80 and 0.81 using raw and weighted vote totals, respectively, indicating strong model performance. We conclude that nipple sizes of female fishers measured during a livetrapping effort can be used as a cost-effective index of the weaning rates of adult female fishers.

Factors affecting juvenile survival are poorly known in the world’s most northern antelope, the endangered saiga (Saiga tatarica), yet these factors are fundamental for understanding what drives population change. We monitored Mongolia saiga (S. tatarica mongolica) calves in Sharga Nature Reserve, western Mongolia, during 2008–2010. Our results showed that male and single calves were heavier than females and twins, respectively. However, we identified no significant differences in seasonal or annual survival rates between sexes or between singletons and twins. Litter size and birth mass varied among years, and there was a negative relationship between these variables. Survival of calves during the 1st year was best explained by the covariates of year and litter size (confounded with body mass), suggesting that interannual variation in environmental conditions influenced twinning rates and body mass, and might play a key role in 1st-year survival. We identified 3 sources of mortality—predation by raptors, foxes (red fox [Vulpes vulpes] and corsac fox [V. corsac]), and lynx (Lynx lynx). Most predation was attributed to raptors, such as golden eagles (Aquila chrysaetos) and cinereous vultures (Aegypius monachus). Our results point to both environmental and biotic factors affecting survival of juvenile saiga.

K. B. Aubry, W. J. Zielinski, M. G. Raphael, G. Proulx, S. W. Buskirk. 2012. Biology and Conservation of Martens, Sables, and Fishers: A New Synthesis. Cornell University Press, New York, New York. 580 pp. ISBN-978-0-8014-5088-4 (hardbound), $75.00. In recent decades, Martes species (martens, fishers, and sables) have garnered the attention of conservation biologists and policy makers over concerns regarding population declines and their important ecological and economic roles. These concerns prompted the establishment of the Martes Working Group and publication of a synthesis on Martes species (Buskirk et al. 1994). Since the 1994 synthesis, field and laboratory studies have filled key information gaps, new avenues of research have evolved (i.e., genetic analyses, pathogen-host ecology, multiscale habitat analyses), and potential impacts of global climate change have been raised. Accordingly, this new volume incorporates research developments of the last 2 decades into our understanding of Martes species. Providing a synthesis of the peer-reviewed literature into a single book, particularly involving multiple taxa, is a daunting task. We commend the editors for their efforts to produce a volume that goes beyond mere proceedings and that focuses on conservation of Martes species through hypothesis-driven research from across broad disciplines and emerging technologies. The book is divided into 5 topic areas that provide the foundation for the included chapters. The editors made a concerted effort to incorporate important advances in the 8 formally recognized species of the genus Martes , inviting 62 scientists from 12 countries to produce the 20 syntheses presented. The editors acknowledge that the treatment of individual species is uneven, with little known about the yellow-throated marten ( Martes flavigula ), the Japanese marten ( M. melampus ), and the Nilgiri marten ( M. gwatkinsii ). The opening section of the book, Evolution and biogeography of the genus Martes , addresses processes that affect Martes species at large spatial or temporal scales. The 1st chapter, Synthesis of Martes evolutionary history , presents the geographic and evolutionary history of the genus with a review of the fossil record and integrates this information with recent genetic …

We studied the home-range and core-area size and overlap of Tehuantepec jackrabbits (Lepus flavigularis) by radiotracking 32 individuals between May 2001 and April 2003 in savanna habitat in the Isthmus of Tehuantepec, Oaxaca, Mexico. Annual home-range and core-area sizes averaged 55 ha 6 8 SE and 8 6 1 ha for 10 adults of both sexes using the 95% and 50% fixed-kernel isopleths, respectively. Seasonal home ranges varied widely for adults, from 15 to 111 ha for females and from 24 to 166 ha for males. Juvenile males had larger seasonal home ranges than did juvenile females (X ¼ 80 and 24 ha). For adult jackrabbits, seasonal home ranges were larger during the 1st year compared to those of the 2nd year of study (X ¼ 87 and 49 ha), particularly for females. Home ranges and core areas of Tehuantepec jackrabbits were comparable in size and overlapped between active periods (nocturnal and crepuscular hours) and inactive periods (diurnal hours). Adults overlapped their home ranges with 1–10 individuals. Home-range overlap among females was greater than among males. Females shared portions of their ranges with other females more frequently than did males with other males. Home-range and overlap analysis suggests that Tehuantepec jackrabbits have polygamous mating behavior and nonterritorial social organization.

We investigated the role of changing abundance of spring foods on female American black bear (Ursus americanus) diet, milk composition, and cub survival in western Massachusetts. We hypothesized that diets would change, percentage milk fat would be higher, and cub survival would be higher in a year when overwintered hard mast was more abundant. We obtained paired samples of milk from 7 adult female bears across consecutive reproductive cycles during which spring diets differed; 1 year followed a bumper acorn (Quercus rubra) crop and estimated spring diets were >25% acorns; the other year followed an extremely poor acorn crop and spring diets were estimated to be 99% skunk cabbage (Symplocarpus foetidus). Postdenning milk was higher in fat (26.7% versus 18.2%; P = 0.0557) during the spring when acorns were abundant, but we did not identify any carryover affect to cub survival. We suggest that adult female black bears compensate for changes in food availability by eating greater volumes of alternative foods, and perhaps allocate resources primarily to milk production; the bears appear to be able to produce milk of adequate quality to sustain cubs, regardless of spring diet.

A pack of 19–29 African wild dogs ( Lycaon pictus ) in the Masai Mara area of Kenya was monitored during July–August 1989 to document their success in capturing various ungulate species. The pack was most successful killing smaller, abundant ungulate prey, and was not less successful when pack size abruptly was reduced; overall hunting success (all species) was 51%. Abundant prey, low competition with other large carnivores, and large size of pack confound conjecture concerning the evolution of pack size.

Numerous studies have suggested that the extent of character divergence observed between two sympatric species reflects the intensity of competition for resources or space. However, the influence of time on divergence is often overlooked. We examined the relationship between time and character divergence in two groups of congeneric, sympatric canids on two continents: South American foxes and African jackals. Character divergence was assessed from measurements of body mass and dental and cranial shape. Divergence time was estimated from data on mitochondrial DNA restriction site polymorphisms. Our findings indicate that African jackals are morphologically similar despite having diverged more than 2 million years ago. By contrast, South American foxes differ substantially in both size and morphology after only 250,000 years of evolution. Thus, the lack of character divergence among the African jackals cannot be explained as a result of very recent common ancestry.

Etude des differences de poids, de mensurations corporelle et crânienne, de pelage en fonction de: sexe, âge, saison pour des Mephitis mephitis du nord-est du Comte d'Itasca