Type:Article

Subject:Cervus elaphus nelsoni
Crop damage
Electric fence
Elk
Mule deer
Odocoileus hemionus
Repellent
Sunflowers
Wildlife damage management
Winged fence

Description:Mule deer (Odocoileus hemionus) and Rocky Mountain elk (Cervus elaphus nelsoni) provide important recreational, ecological, and economic benefits, but can also cause substantial damage to agricultural crops. Cervid damage to agriculture creates challenges for wildlife agencies responsible for minimizing crop depredation while maintaining healthy deer and elk populations. Sunflower producers in southwestern Colorado, USA, have experienced high deer and elk damage and were interested in temporary methods to reduce damage that were cost-effective for rotational crops. To address this challenge, we investigated 3 temporary, non-lethal exclusion and repellent techniques for reducing deer and elk damage to sunflowers: 1) a polyrope electric fence, 2) the chemical repellent Plantskydd™, and 3) a winged fence. During July through October 2011 and 2012, we used a randomized block design to test the efficacy of these techniques by quantifying cervid damage to sunflowers and the number of deer and elk tracks traversing treatment and control plot boundaries. Using generalized linear mixed models we found that polyrope electric fences reduced deer and elk damage and presence within plots, while the repellent and winged fences did not reduce ungulate activity. Polyrope electric fences may be a suitable tool in areas where wildlife management agencies want to maintain deer and elk populations but reduce seasonal damage by cervids to high-value crops. In Colorado, use of an effective exclusion technique such as polyrope electric fence could also decrease the need for lethal depredation permits and damage compensation payments, and increase satisfaction among producers and the public. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. [show more]

Type:Article

Subject:Black bear
Cause-specific mortality
Colorado
Conflict
Homing
Survival
Translocation
<em>Ursus americanus</em>

Description:From 1995 to 1997, black bears (Ursus americanus) involved in conflicts with humans in southeastern Colorado, USA, were radiocollared, translocated, and monitored by the Colorado Division of Wildlife to evaluate translocation as a management tool for problem black bears. Specific objectives were to 1) determine postrelease movement patterns of relocated black bears, and 2) estimate cumulative incidence and survival functions. Subadults did not move as far after translocation as adults and less frequently oriented toward the capture site (29% of subad vs. 51% of ad). No subadults returned to the vicinity of capture, whereas 33% of adults did. We used a cause-specific hazards model with a constant age effect across the cause-specific hazards to estimate annual survival rate for translocated adult bears (0.50, 95% credible interval CI = 0.36–0.65) and for subadult bears (0.28, 95% CI = 0.12–0.48). The annual probability of dying due to repeat conflict behavior was slightly lower (0.22 [95% CI = 0.13–0.33] and 0.32 [95% CI = 0.19–0.47]) for adults and subadults, respectively, compared with nonconflict mortalities (0.28 [95% CI = 0.17–0.40] and 0.40 [95% CI = 0.25–0.56]). Based on bears that were not involved in known repeat human–bear conflicts, translocation success was 0.64 (95% CI = 0.49–0.78) and 0.58 (95% CI = 0.42–0.73) for adults and subadults, respectively. Translocation of problem bears had mixed success relative to repeat nuisance activity in Colorado, but should remain a viable management option. Managers should make decisions on the appropriateness of translocation based on the characteristics of the bear, identification of an adequate release site, potential effect of the translocation on the release-site bear population, and other available options. [show more]

Type:Article

Subject:Adaptive management
Cougar
Exploitation
Population trend
<em>Puma concolor</em>
Sex–age composition

Description:Cougar (Puma concolor) management has been hindered by inability to identify population trends. We documented changes in sex and age of harvested cougars during an experimentally induced reduction in population size and subsequent recovery to better understand the relationship between sex-age composition and population trend in exploited populations. The cougar population in the Snowy Range, southeast Wyoming, was reduced by increased harvest (treatment phase) from 58 independent cougars (>1 year old) (90% C***l = 36–81) in the autumn of 1998 to 20 by the spring of 2000 (mean exploitation rate = 43%) and then increased to 46 by spring 2003 following 3 years of reduced harvests (mean exploitation rate = 18%). Pretreatment harvest composition was 63% subadults (1.0–2.5 years old), 23% adult males, and 14% adult females (2 seasons; n = 22). A reduction in subadult harvest, an initial increase followed by a reduction in adult male harvest, and a steady increase in adult female harvest characterized harvest composition trends during the treatment phase. Harvest composition was similar at high and low densities when harvest was light, but proportion of harvested subadult males increased at low density as they replaced adult males removed during the treatment period (high harvest). While sex ratio of harvested cougars alone appears of limited value in identifying population change, when combined with age class the 2 appear to provide an index to population change. Composition of the harvest can be applied to adaptively manage cougar populations where adequate sex and age data are collected from harvested animals. [show more]

Type:Article

Subject:Constraints
Motivations
Nontraditional path hunter
Recruitment
Socialization

Description:Anecdotal evidence suggests that adults lacking previous hunting experience and family support for hunting comprise a growing proportion of new hunters. Empirical evidence of such a trend is lacking. Furthermore, hunting motivations and constraints for these “nontraditional path hunters” (NTPHs) have not been well documented. We articulate a strategy for identifying potential NTPHs in New York, describe socialization mechanisms initiating NTPHs into hunting, and explore motivations and constraints of these hunters. Data were collected using a Web-based survey of 3,605 NTPHs identified among 2014 Sportsman Education course graduates in New York. We found that many NTPHs were initiated by friends and co-workers, and their motivations and constraints were similar to traditional hunters. These findings suggest that NTPHs are not a panacea to the trend of declining numbers of hunters in New York. [show more]

Type:Article

Subject:Feline foamy virus
Epidemiology
Retrovirus
<em>Spumaretrovirus</em>
Mountain lion
<em>Puma concolor</em>
ELISA

Description:Feline foamy virus (FFV) is a retrovirus that has been detected in multiple feline species, including domestic cats (Felis catus) and pumas (Puma concolor). FFV results in persistent infection but is generally thought to be apathogenic. Sero-prevalence in domestic cat populations has been documented in several countries, but the extent of viral infections in nondomestic felids has not been reported. In this study, we screened sera from 348 individual pumas from Colorado, Southern California and Florida for FFV exposure by assessing sero-reactivity using an FFV anti-Gag ELISA. We documented a sero-prevalence of 78.6% across all sampled subpopulations, representing 69.1% in Southern California, 77.3% in Colorado, and 83.5% in Florida. Age was a significant risk factor for FFV infection when analyzing the combined populations. This high prevalence in geographically distinct populations reveals widespread exposure of puma to FFV and suggests efficient shedding and transmission in wild populations. [show more]

Type:Article

Subject:Genetic differentiation
Heterozygosity fitness correlation
Migration
Mule deer
Multilocus heterozygosity
<em>Odocoileus hemionus</em>
Single-locus heterozygosity
Wildlife

Description:The relationship between genetic variation and phenotypic traits is fundamental to the study and management of natural populations. Such relationships often are investigated by assessing correlations between phenotypic traits and heterozygosity or genetic differentiation. Using an extensive data set compiled from free-ranging mule deer (Odocoileus hemionus), we combined genetic and ecological data to (i) examine correlations between genetic differentiation and migration timing, (ii) screen for mitochondrial haplotypes associated with migration timing, and (iii) test whether nuclear heterozygosity was associated with condition. Migration was related to genetic differentiation (more closely related individuals migrated closer in time) and mitochondrial haplogroup. Body fat was related to heterozygosity at two nuclear loci (with antagonistic patterns), one of which is situated near a known fat metabolism gene in mammals. Despite being focused on a widespread panmictic species, these findings revealed a link between genetic variation and important phenotypes at a fine scale. We hypothesize that these correlations are either the result of mixing refugial lineages or differential mitochondrial haplotypes influencing energetics. The maintenance of phenotypic diversity will be critical to enable the potential tracking of changing climatic conditions, and these correlates highlight the need to consider evolutionary mechanisms in management, even in widely distributed panmictic species. [show more]

Type:Article

Subject:Feline foamy virus
Retrovirus
Cross-species transmission
Puma
Domestic cat
Recombination

Description:Emerging viral outbreaks resulting from host switching is an area of continued scientific interest. Such events can result in disease epidemics or in some cases, clinically silent outcomes. These occurrences are likely relatively common and can serve as tools to better understand disease dynamics, and may result in changes in behavior, fecundity, and, ultimately survival of the host. Feline foamy virus (FFV) is a common retrovirus infecting domestic cats globally, which has also been documented in the North American puma (Puma concolor). The prevalent nature of FFV in domestic cats and its ability to infect wild felids, including puma, provides an ideal system to study cross-species transmission across trophic levels (positions in the food chain), and evolution of pathogens transmitted between individuals following direct contact. Here we present findings from an extensive molecular analysis of FFV in pumas, focused on two locations in Colorado, and in relation to FFV recovered from domestic cats in this and previous studies. Prevalence of FFV in puma was high across the two regions, ∼77 per cent (urban interface site) and ∼48 per cent (rural site). Comparison of FFV from pumas living across three states; Colorado, Florida, and California, indicates FFV is widely distributed across North America. FFV isolated from domestic cats and pumas was not distinguishable at the host level, with FFV sequences sharing >93 per cent nucleotide similarity. Phylogenetic, Bayesian, and recombination analyses of FFV across the two species supports frequent cross-species spillover from domestic cat to puma during the last century, as well as frequent puma-to-puma intraspecific transmission in Colorado, USA. Two FFV variants, distinguished by significant difference in the surface unit of the envelope protein, were commonly found in both hosts. This trait is also shared by simian foamy virus and may represent variation in cell tropism or a unique immune evasion mechanism. This study elucidates evolutionary and cross-species transmission dynamics of a highly prevalent multi-host adapted virus, a system which can further be applied to model spillover and transmission of pathogenic viruses resulting in widespread infection in the new host. [show more]

Type:Article

Subject:Gold mining
Upper Arkansas River
Habitat restoration

Description:Over a century of metals pollution and channel disturbance associated with historical mining, land use, and water development contributed to degradation of aquatic and riparian habitat within the upper Arkansas River watershed near Leadville, Colorado. Following water quality remediation, habitat restoration was conducted for a 17.7-km reach characterized as an overwide channel that lacked velocity refuge and overwinter habitat for salmonids. The primary goals of restoration were to improve populations of Brown Trout Salmo trutta and individual fish health, with a target to increase fish metrics by 10% within 5 years after restoration. Fish metrics included Brown Trout density, biomass, quality, and relative weight, where quality was defined as the density of Brown Trout over 356 mm in length. Changes in all fish metrics were evaluated with a before-after–control-impact study design that utilized five control sites and five impact sites. Biomass was the only metric that exhibited a significant interaction between site type and period (before and after), with increases of 12% and 21% at control and impact sites, respectively. Increased density (10%) and relative weight (2.4%) were observed across all sites regardless of type. Changes at individual sites were less evident, with only one impact site showing significant increases in biomass (99%) and quality Brown Trout (306%). These results suggest that Brown Trout populations within the upper Arkansas River have continued to improve following large-scale water quality remediation and stream restoration efforts. Additional monitoring is recommended to evaluate long-term trends and inform adaptive management. [show more]

Type:Article

Subject:Central Rocky Mountains
Cougar
Gene flow
Genetic structure
Metapopulation
Microsatellite DNA
Panmixia

<em>Puma concolor</em>

Description:We examined the genetic structure of 5 Wyoming cougar (Puma concolor) populations surrounding the Wyoming Basin, as well as a population from southwestern Colorado. When using 9 microsatellite DNA loci, observed heterozygosity was similar among populations (H_o = 0.49–0.59) and intermediate to that of other large carnivores. Estimates of genetic structure (F_St = 0.028, R_St = 0.029) and number of migrants per generation (Nm) suggested high gene flow. Nm was lowest between distant populations and highest among adjacent populations. Examination of these data, plus Mantel test results of genetic versus geographic distance (P ≤ 0.01), suggested both isolation by distance and an effect of habitat matrix. Bayesian assignment to population based on individual genotypes showed that cougars in this region were best described as a single panmictic population. Total effective population size for cougars in this region ranged from 1,797 to 4,532 depending on mutation model and analytical method used. Based on measures of gene flow, extinction risk in the near future appears low. We found no support for the existence of metapopulation structure among cougars in this region. [show more]

Type:Article

Subject:Bridger-Teton National Forest
Depredation
Domestic cattle
Grand Teton National Park
Grizzly bear
Nuisance bear management
<em>Ursus arctos</em>

Description:We determined cause of death for 182 cattle found dead on 2 adjacent public land grazing allotments in northwest Wyoming during 1994-96. Grizzly bears (Ursus arctos) killed fifty-one calves and 6 adults, representing 1.1% (mean) of the annual calf herd and 0.1% of the annual adult herd. An additional 0.9-1.8% of remaining calves were missing each year. Black bears (U. americanus), although present, were not implicated in cattle depredation. We believe that missing calves experienced depredation similar to discovered calves because the proportion killed by bears was similar for those equipped with mortality-sensing transmitters and unmarked calves (P = 0.73). Thus, estimated depredation equaled 78 calves or 1.3-2.2% of the annual calf herd. All observed depredation occurred at night (n = 9). Kills were separated by a mean of 3 days (n = 50) and occurred between 16 June and 13 September (median = 9 August). Radiotagged grizzly bears (n = 17) spent a greater proportion of time in the study area while depredations were occurring, and 10 were located near cattle more frequently than expected (P < 0.05), but most did not kill cattle. Although individuals from all sex and age (subadult, adult) groups except subadult males killed cattle, 3 adult males were responsible for 90% of confirmed losses. We employed management actions including euthanasia, translocation, and aversive conditioning to remove chronic depredators. No depredations were discovered following absence of the 3 depredating males in 1996, unlike the previous 2 years when losses continued for an additional 4 to 6 weeks. This suggests that removal of chronic depredators can reduce losses. Other bears did not become more depredatory, although many were known to utilize cattle carcasses. Removal of cattle carcasses during 1996 appeared to reduce bear densities but did not deter depredatory bear behavior. Identification and removal of depredatory individuals appears key in addressing conflicts with grizzly bears on rangelands. [show more]