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The white‐tailed deer (Odocoileus virginianus) of Missouri have undergone changes in the past 100 years. From a historical estimate of 700,000 individuals, deer were nearly extirpated from the state following overexploitation in the late 1800s. Despite this, deer have since undergone a rapid expansion to the current population of 1.4 million. Because of this complex recent history, we sought to understand the levels and distribution of genetic diversity in deer across Missouri. We genotyped 751 deer at 10 microsatellite loci and used genetic distance metrics and Bayesian clustering analyses to identify distinct genetic groups. We also sequenced the mitochondrial control region from a subset (n = 248) of deer to identify historical lineages. We found high levels of nuclear marker diversity (HE = 0.818) and low, but statistically significant, levels of differentiation among regions. The high level of mitochondrial diversity (48 haplotypes; haplotype diversity = 0.621–0.964) is reflected in a haplotype network that suggests the persistent signature of translocated lineages. Overall, the white‐tailed deer of Missouri now represent a highly diverse population with no indication that there are barriers to gene flow. This will be an important consideration for the management of disease resistance and spread throughout the state. © 2018 The Wildlife Society. White‐tailed deer were nearly extirpated from Missouri following overexploitation in the late 1800s but have since undergone a rapid expansion to the current population of 1.4 million. We report high levels of genetic diversity and low levels of differentiation across the state, which will be an important consideration for the management of disease resistance and spread. [ABSTRACT FROM AUTHOR]

Across much of North America, river otter (Lontra canadensis) populations were extirpated or greatly reduced by the early 20th century. More recently, reintroductions have resulted in restored populations and the recommencement of managed trapping. Perhaps the best example of these river otter reintroductions occurred in Missouri, regarded as one of the most successful carnivore recovery programs in history. However, abundance estimates for river otter populations are difficult to obtain and often contentious when used to underpin management activities. We assessed the value of latrine site monitoring as a mechanism for quantifying river otter abundance. Analyses of fecal DNA to identify individual animals may result in an improved population estimate and have been used for a variety of mammal species. We optimized laboratory protocols, redesigned existing microsatellite primers, and calculated genotyping error rates to enhance genotyping success for a large quantity of river otter scat samples. We also developed a method for molecular sexing. We then extracted DNA from 1,421 scat samples and anal sac secretions (anal jelly) collected during latrine site counts along 22-34-km stretches representing 8-77% of 8 rivers in southern Missouri in 2009. Error rates were low for the redesigned microsatellites. We obtained genotypes at 7-10 microsatellite loci for 24% of samples, observing highest success for anal jelly samples (71%) and lowest for fresh samples (collected within 1 day of defecation). We identified 63 otters (41 M, 22 F) in the 8 rivers, ranging from 2 to 14 otters per river. Analyses using program CAPWIRE resulted in population estimates similar to the minimum genotyping estimate. Density estimates averaged 0.24?otters/km. We used linear regression to develop and contrast models predicting population size based on latrine site and scat count indices, which are easily collected in the field. Population size was best predicted by a combination of scats per latrine and latrines per kilometer. Our results provide methodological approaches to guide wildlife managers seeking to initiate similar river otter fecal genotyping studies, as well as to estimate and monitor river otter population sizes. [ABSTRACT FROM AUTHOR]

Recently, a number of papers have addressed the use of pedigrees in the study of wild populations, highlighting the value of pedigrees in conservation management. We used pedigrees to study the horses (Equus caballus) of Assateague Island National Seashore, Maryland, USA, one of a small number of free-ranging animal populations that have been the subject of long-term studies. This population grew from 28 in 1968 to 175 in 2001, causing negative impacts on the island ecosystem. To minimize these effects, an immunocontraception program was instituted, and horse numbers are slowly decreasing. However, there is concern that this program may negatively affect the genetic health of the herd. We found that although mitochondrial DNA diversity is low, nuclear diversity is comparable to that of established breeds. Using genetic data, we verified and amended maternal pedigrees that had been primarily based on behavioral data and inferred paternity using genetic data along with National Park Service records of the historic ranges of males. The resulting pedigrees enabled us to examine demography, founder contributions, rates of inbreeding and loss of diversity over recent generations, as well as the level of kinship among horses. We then evaluated the strategy of removing individuals (using nonlethal means) with the highest mean kinship values. Although the removal strategy increased the retained diversity of founders and decreased average kinship between individuals, it disproportionately impacted sizes of the youngest age classes. Our results suggest that a combined strategy of controlled breeding and immunocontraception would be more effective than removing individuals with high mean kinships in preserving the long-term health and viability of the herd. [ABSTRACT FROM AUTHOR]