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Ungulate species have consistently been a major focus of reintroductions to their native ranges. Bighorn sheep (Ovis canadensis) are an ecologically sensitive species, and have experienced population declines throughout their historic range; bighorn sheep inhabited the Black Hills region of South Dakota but were extirpated from the area due to anthropogenic impacts in the early 1900s. To continue to restore populations to the area, we translocated 26 bighorn sheep from Alberta, Canada to the Deadwood Region of the Black Hills. Bighorn sheep were fitted with VHF or GPS collars and monitored throughout the duration of the study (Feb 2015–Jan 2017). Our objectives were to evaluate movement patterns post-release of bighorn sheep in the translocated Deadwood bighorn sheep herd. We utilized 3 types of home-range analyses based on collar data; kernel density estimation (KDE), minimum convex polygon (MCP), and Brownian Bridge Movement Models (BBMM) were used to estimate home-ranges year 1, year 2, and for the duration of the study. Home-range size utilizing KDE (95%; $$\overline{x}$$ = 41.41 km2, SE = 10.50), minimum convex polygon (95%; $$\overline{x}$$ = 55.73 km2, SE = 15.04), and BBMM (95%; $$\overline{x}$$ = 32.95 km2, SE = 4.67) differed among methods. Year 1 home-range sizes (95% BBMM; $$\overline{x}$$ = 40.01 km2) were larger than year 2 (95% BBMM; $$\overline{x}$$ = 4.08 km2) home-range sizes. Travel distances were also larger in year 1 ( $$\overline{x}$$ = 431.80 km) than year 2 ( $$\overline{x}$$ = 368.77 km). Our results indicate that after an acclimation period, which included individual dispersal, the translocated Deadwood bighorn sheep herd settled into smaller home-ranges near the release site.

Bighorn sheep (Ovis canadensis) were once extirpated from the Black Hills region of South Dakota, U.S.A., mirroring declining populations throughout North America. Since the 1960s, several reintroductions have occurred in the Black Hills to reestablish populations, with varying success. We translocated 26 bighorn sheep from Alberta, Canada, to the Black Hills (February 2015) to restore bighorn sheep to their historic range. Due to prior examinations of cause‐specific survival, subsequent genetic diversity and disease prevalence analyses were required to evaluate success of the restoration effort. We measured a mean allelic diversity of 5.23 (SE = 0.44 [mean number of alleles]) and an observed heterozygosity of 0.71 (SE = 0.06; expected = 0.64 ± 0.05) in the translocated individuals. Translocated bighorn sheep tested negative for Mycoplasma ovipneumoniae at capture. An autogenous vaccine was administered prior to release in an attempt to safeguard the translocated bighorn sheep from infection with a strain known to be resident in adjacent bighorn sheep populations. However, the year following the translocation, a different strain of M. ovipneumoniae was associated with a pneumonia outbreak that resulted in 57.9% mortality. Our results suggest that allelic diversity and heterozygosity were sufficient for long‐term herd establishment, reducing the potential for founder effects. However, the overwhelming mortality associated with pneumonia, via the transfer of M. ovipneumoniae from an unknown source, limited the success or our reintroduction efforts. Successful attempts to restore bighorn sheep to their historic ranges must consider and mitigate potential routes for M. ovipneumoniae transmission pre‐ and post‐reintroduction.

Long-term datasets are becoming increasingly important for assessing population- and species-level responses to a changing environment. Programs that record morphological measurements of horns, antlers, and pronghorns were established in the early- to mid-20th century to collect biological information about animals that possess large horns, antlers, or pronghorns, which could be used to assess the effectiveness of conservation efforts for large mammals in North America. The general relevance of record books has been questioned because of the minimum size requirements for inclusion in a record book, which may mask trends when changes in the population occur. We compared trends in size of antlers, horns, and pronghorns through time using records from three records programs with different minimum size requirements to evaluate the influence of entry requirements on temporal trends. We also investigated whether horn, antler, or pronghorn size affected the probability of specimens being submitted to a records program. Only two of 17 categories exhibited less-pronounced trends in the record book with the highest size requirements for entry, and in two categories trends were more pronounced. Although societal interest in submitting eligible specimens increased slightly over time in one of six categories, the probability of voluntary entry was largely random and not affected by year of harvest or size of specimen. In contrast to previous criticisms, trends in record books should not be expected to represent the size of all males within a population. Instead, our evaluation indicates that the records programs we examined can provide a useful resource for assessing long-term changes in phenotypic characteristics of ungulates, but importantly, they represent the respective range of sizes within which each program collects data.

Bighorn Sheep (Ovis canadensis) historically inhabited the Black Hills region of South Dakota, but the species was extirpated from the area in the early 1900s concurrent with declines in population throughout their entire North American range. Translocation is a common management tool allowing for accelerated colonization of historic Bighorn Sheep habitat, but many attempts are unsuccessful. Mountain Lions (Puma concolor) and pneumonia are generally considered the most common limiting factors to Bighorn Sheep populations. Twenty-six Bighorn Sheep were translocated from Alberta, Canada to the Deadwood region of the northern Black Hills, an area with both a resident Mountain Lion population and potential for contact with Domestic Sheep (Ovis aries) and Goats (Capra hircus), known carriers of pathogens that are lethal to Bighorn Sheep. Adult survival and natality increased the population substantially in year 1, however, the only breeding-age male was euthanized owing to concerns about potential for pathogen transmission from Domestic Sheep and Goats. In year 2, the population experienced a pneumonia outbreak, resulting in 57.9% of all mortalities during the study period. Mountain Lion predation was not detected, nor was direct contact with Domestic Sheep or Goats observed. Intensive monitoring was critical in determining the outcome of the translocation.

We investigated survival, reproduction, and population growth (λ) for a declining elk (Cervus canadensis nelsoni) population in South Dakota, USA, 2011–2015. We obtained survival data from 125 calves and 34 yearlings. We determined survival and pregnancy rates for 42 adults (2–8 years old) and 39 old adults (≥8 years old). We combined population vital rates into a matrix model, which indicated a slightly growing population but with considerable uncertainty (λ¯ = 1.03, 95% CI = 0.93–1.13). Our elasticity analysis suggested asymptotic growth rates were most sensitive to proportional changes in old adult and adult female survival, followed by proportional changes in calf and yearling survival. Our life-stage simulation analysis further supported asymptotic growth rates being most sensitive to variation in survival, and most of the variation in λ we observed was a consequence of variation in annual calf survival (R2 = 0.58). Annual calf survival was low (0.26, 95% CI = 0.05–0.52), and puma (Puma concolor) predation was the primary cause-specific mortality factor of calves (0.63, 95% CI = 0.51–0.76). Adult female survival was near its biological maximum (0.95, 95% CI = 0.87–0.99); therefore, managing for increased calf survival may be the most practical strategy for promoting elk population growth in this system. Managing this puma population at the lower end of the population objective and reducing white-tailed deer (Odocoileous virginianus) numbers (primary prey source) may allow for elk population growth in this system. © 2017 The Wildlife Society.

Following recent elk (Cervus canadensis nelsoni) population declines in South Dakota, we evaluated space use of elk in response to biotic and abiotic covariates at a regional scale. We built Brownian bridge movement models to examine summer (parturition date to 31 October) and winter (1 November to following year's parturition date) seasonal movements of radio-collared female elk from 2011 to 2013 at 99% home range and 50% core area contour levels. Our primary objective was to evaluate seasonal movements of female elk in response to drought, vegetation resources, and road density. Higher road densities and increased amounts of open-canopied vegetation were correlated with an increase in core area size. Elk inhabiting open-canopied areas may increase their movements in an attempt to find cover and avoid disturbance factors associated with roads. The high levels of human visitor activity in the Black Hills and accompanying disturbance of wildlife highlight the importance of management strategies that consider elk security cover, or lack of cover in open-canopied areas, when devising road management strategies.

Percent of body fat and physiological stress are important correlates to wildlife demographics. We studied winter percent of body fat and physiological stress levels for a declining elk (Cervus canadensis nelsoni) population in South Dakota, 2011–2013. We obtained percent of winter body fat, pregnancy status, lactation status, and physiological stress data from 58 adult females (2+ years old). We compared physiological stress level data from 2011 with data collected from this same herd when elk densities were much higher (1995–1997). Our objectives were to determine percent of body fat during winter, examine if winter body fat was correlated with pregnancy and lactation status, and quantify and compare physiological stress hormone values from elk in the mid-1990s. Probability of being pregnant increased with higher winter nutritional condition, or percent of body fat; whereas females with a higher probability of previously lactating were lower in winter body fat. Mean fecal glucocorticoid metabolite (FGM) levels in 2011 (mean = 47.78 ng/g, SE = 2.37) were higher during summer compared to data collected in 1995–1997 (mean = 34.21 ng/g, SE = 3.71); however, mean FGM levels during winter did not differ between the two time periods. Although summer levels of FGM have significantly increased since the mid-1990s, we caution against any interpretation of increased FGM levels on elk fitness, as it may not infer biological significance. Mean winter percent of body fat of elk was lower when compared to other populations in the west but this difference does not appear to be limiting vital rates and population growth for this elk herd. We recommend future research focus on summer/autumn data collection to provide a more comprehensive understanding of percent of body fat for elk in our region.

Chronic pathogen carriage is one mechanism that allows diseases to persist in populations. We hypothesized that persistent or recurrent pneumonia in bighorn sheep (Ovis canadensis) populations may be caused by chronic carriers of Mycoplasma ovipneumoniae (Mo). Our experimental approach allowed us to address a conservation need while investigating the role of chronic carriage in disease persistence.We tested our hypothesis in two bighorn sheep populations in South Dakota, USA. We identified and removed Mo chronic carriers from the Custer State Park (treatment) population. Simultaneously, we identified carriers but did not remove them from the Rapid City population (control). We predicted removal would result in decreased pneumonia, mortality, and Mo prevalence. Both population ranges had similar habitat and predator communities but were sufficiently isolated to preclude intermixing.We classified chronic carriers as adults that consistently tested positive for Mo carriage over a 20‐month sampling period (n = 2 in the treatment population; n = 2 in control population).We failed to detect Mo or pneumonia in the treatment population after chronic carrier removal, while both remained in the control. Mortality hazard for lambs was reduced by 72% in the treatment population relative to the control (CI = 36%, 91%). There was also a 41% reduction in adult mortality hazard attributable to the treatment, although this was not statistically significant (CI = 82% reduction, 34% increase). Synthesis and Applications: These results support the hypothesis that Mo is a primary causative agent of persistent or recurrent respiratory disease in bighorn sheep populations and can be maintained by a few chronic carriers. Our findings provide direction for future research and management actions aimed at controlling pneumonia in wild sheep and may apply to other diseases., In this experimental study, we removed chronic shedders of Mycoplasma ovipneumoniae from a pneumonic bighorn sheep population and followed adult and juvenile survival in both the population and a nearby control population. The treatment population had significantly higher survival across age classes and no pneumonia or M. ovipneumoniae, whereas the control population suffered high mortality rates due to pneumonia. Pneumonia mortality is a widespread and persistent threat to bighorn sheep populations, and this is the first management action that has successfully removed pneumonia from a herd.

Elk Cervus canadensis nelsoni in the Black Hills, South Dakota, have been declining since 2006 and there is concern by resource managers and hunters that puma Puma concolor predation may be contributing to declining herds. We evaluated characteristics at sites where puma successfully killed elk in the Black Hills of South Dakota. We evaluated characteristics at coarse (79-ha plots) and fine (0.2-ha plot) scales across the landscape. Our primary objective was to obtain a better understanding of vegetation and terrain characteristics that may have facilitated greater susceptibility of elk to predation by puma. We evaluated effects of road density, terrain heterogeneity, probability of elk use, and vegetation variables at 62 puma kill sites of elk and 186 random sites to identify key landscape attributes where elk were killed by puma. Elk were killed by puma in high use areas. Elk were also killed in areas that had greater amounts of edge and intermediate ruggedness at the coarse scale. Further, elk were kil...

In light of local population declines and poor calf survival, we investigated visual obstruction as potential elk (Cervus elaphus) calf hiding cover at birth sites. We hypothesized that female elk would use hiding cover (i.e., visual obstruction) in order to conceal their calves at the birth site and reduce vulnerability to predation. Selection of hiding cover has been well documented at calf bedding sites subsequent to parturition; however, because of variably reported results from prior studies, it is unclear whether hiding cover is selected at the immediate birth site. We estimated visual obstruction of hiding cover, measured understory vegetation height, and categorized the dominant form of hiding cover at 65 birth sites and 116 random sites within the Black Hills, South Dakota. We found no significant differences in visual obstruction, vegetation height, or selection of dominant hiding cover categories between birth and random sites within forest and grassland systems. We surmise that selec...

We studied elk (Cervus canadensis nelsoni) parturition sites at coarse (314-km2 and 7-km2) and fine (0.2-ha) scales in the Black Hills, South Dakota, 2011–2013, following a period of population decline and poor calf recruitment. Our objective was to test whether female elk selected parturition sites across spatial scales in association with forage, terrain ruggedness, road density, or hiding and security cover. At coarse scales in forests and grasslands, female elk selected sites in areas with greater proportions of vegetation communities that provided forage (56–74% of area) and more rugged topography (194–248 m) than found at random. At coarse scales in grasslands, elk selected sites in areas with lower road densities (≤1.24 km/plot). At the fine scale in forests and grasslands, female elk selected sites in areas with intermediate slope (19%), closer to water (355–610 m), and far from roads (541–791 m). Further, elk in forests and grasslands selected sites with intermediate security cover (50–88 m). We hypothesize elk selected for intermediate rugged terrain at larger scales for security from high road densities and human disturbance, but these areas may have placed elk in riskier environments for puma (Puma concolor) predation. Forest management that maintains open-canopied vegetation communities in less rugged areas and prevents ponderosa pine (Pinus ponderosa) encroachment of meadows to provide forage may be beneficial for elk. Further, elk parturition sites occurred close to roads, particularly on public lands, and agencies should consider road-use restrictions and vegetation buffers beside roads in areas with less rugged terrain, which may provide favorable calving habitat. © 2015 The Wildlife Society.

Since 1993, elk (Cervus canadensis nelsoni) abundance in the Black Hills of South Dakota has been estimated using a detection probability model previously developed in Idaho, though it is likely biased because of a failure to account for visibility biases under local conditions. To correct for this bias, we evaluated the current detection probability across the Black Hills during January and February 2009–2011 using radio-collared elk. We used logistic regression to evaluate topographic features, habitat characteristics, and group characteristics relative to their influence on detection probability of elk. Elk detection probability increased with less vegetation cover (%), increased group size, and more snow cover (%); overall detection probability was 0.60 (95% CI 0.52–0.68), with 91 of 152 elk groups detected. Predictive capability of the selected model was excellent (ROC = 0.807), and prediction accuracy ranged from 70.2% to 73.7%. Cross-validation of the selected model with other population estimation methods resulted in comparable estimates. Future applications of our model should be applied cautiously if characteristics of the area (e.g., vegetation cover >50%, snow cover >90%, group sizes >16 elk) differ notably from the range of variability in these factors under which the model was developed.

Black-backed Woodpeckers (Picoides arcticus) are a disturbance-dependent species that occupy recently burned forest and mountain pine beetle (MPB) infestations. Forest management practices that reduce the amount of disturbed forest may lead to habitat loss for Black-backed Woodpeckers, which have recently been petitioned for listing under the Endangered Species Act. We studied home range size and resource selection of Black-backed Woodpeckers occupying habitat created by summer wildfire, fall prescribed fire, and MPB infestations in the Black Hills, South Dakota. We studied home range size and resource selection by attaching radio-transmitters to adult Black-backed Woodpeckers. We estimated home range size using fixed kernel density techniques (n = 28 in habitat created by summer wildfire, n = 19 in habitat created by fall prescribed fire, and n = 27 in MPB infestations). We evaluated resource selection with a random-effects discrete choice model in a Bayesian framework (n = 5 in habitat created by summer wildfire, n = 16 in habitat created by fall prescribed fire, and n = 8 in habitat created by MPB infestations). Home range size was smallest in 1–2 year post summer wildfire habitat (mean home range size = 79 ha) and 2-year post fall prescribed fire habitat (mean home range size = 143 ha). Home range size was intermediate in MPB infestations (mean home range size = 307 ha) and was greatest in 3–4 year post fire habitat (mean summer wildfire home range size = 430 hectares, mean fall prescribed fire home range size = 460 ha). The relative probability that a Black-backed Woodpecker used a tree increased with increasing diameter at breast height (DBH) and basal area and was greatest on disturbance-killed trees. These results suggest 1–2 year post summer wildfire habitat may have the greatest relative value to Black-backed Woodpeckers and that MPB infestations may be more important as post-fire habitats age. We recommend retaining patches of 1–2 year post summer wildfire habitat that are at least 200 ha by exempting portions of recently burned forest from salvage logging. This recommendation can be accomplished by exempting salvage logging in summer wildfires 400 ha. Ideally, recently burned forest patches should be composed of P27 m 2 basal area/ha of trees that burned at moderate or high severity, with at least 40% of the basal area composed of trees P27 cm DBH.