Pathogen Exposure Patterns among Sympatric Populations of Bighorn Sheep, Mule Deer and Cattle

Spontaneous paratuberculosis was studied in free-ranging and captive bighorn sheep ( Ovis canadensis), and Rocky Mountain goats ( Oreamnos americanus). Lesions of paratuberculosis in these species resembled the disease in domestic sheep and goats. Mycobacterium paratuberculosis cultured from bighorn sheep was used to orally infect bighorn x mouflon ( Ovis musimon) hybrid sheep, elk ( Cervus elaphus nelsoni), mule deer ( Odocoileus hemionus), and white-tailed deer ( Odocoileus virginianus), Clinical paratuberculosis developed only in mule deer and was characterized by poor growth and diarrhea. Gross lesions were mild in all species. Enlargement of mesenteric lymph nodes was mild to moderate; the wall of the distal small intestine was affected minimally. Focal to diffuse infiltrates of epithelioid macrophages and giant cells occurred in the cortex of mesenteric lymph nodes, around mesenteric lymphatics, and in the intestinal mucosa. Extraintestinal lymph nodes, spleen, liver, and lung were involved in some animals; focal necrosis and mineralization was present in all species but was severe and widespread in the ceervids.

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Gastropod intermediate hosts of lungworms (Nematoda: Protostrongylidae) on a bighorn sheep winter range: aspects of transmission

Canadian Journal of Zoology ◽

10.1139/z90-278 ◽

1990 ◽

Vol 68 (9) ◽

pp. 1976-1982 ◽

Cited By ~ 3

Author(s):

L. A. Robb ◽

W. M. Samuel

Keyword(s):

Mule Deer ◽

Bighorn Sheep ◽

Ovis Canadensis ◽

Intermediate Hosts ◽

Gastropod Species ◽

Winter Range ◽

Infective Larvae ◽

Third Stage ◽

Inherent Problem

A study of the gastropod intermediate hosts of the lungworms Protostrongylus stilesi and Protostrongylus rushi was conducted on a bighorn sheep (Ovis canadensis canadensis) winter range in southwestern Alberta, 1984–1985. Over 7000 gastropods were examined. Seven gastropod species were infected with Protostrongylus-type larvae: the predominant intermediate hosts were Euconulus fulvus (6.8% infected), Vertigo gouldi (5.6%), and Vertigo modesta (3.2%). Prevalence of third-stage (infective) larvae was highest in September and April, coinciding with use of the winter range by bighorn sheep. An index of lungworm availability to sheep was highest in autumn in the margins of aspen copses and in spring in the grassy openings. Copses were used extensively by sheep in autumn, and open areas were used in the spring. Presence of a mule deer (Odocoileus h. hemionus) lungworm, Orthostrongylus macrotis, was an inherent problem.

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Niche relationships within a guild of ungulate species in Yellowstone National Park, Wyoming, following release from artificial controls

Canadian Journal of Zoology ◽

10.1139/z94-183 ◽

1994 ◽

Vol 72 (8) ◽

pp. 1383-1394 ◽

Cited By ~ 39

Author(s):

Francis J. Singer ◽

Jack E. Norland

Keyword(s):

Cervus Elaphus ◽

Rank Order ◽

Mule Deer ◽

Bighorn Sheep ◽

Ovis Canadensis ◽

Bison Bison ◽

Exclusion Principle ◽

Antilocapra Americana ◽

Artemisia Frigida ◽

Niche Relationships

Niche relationships and diet overlaps were compared among elk (Cervus elaphus), bison (Bison bison), bighorn sheep (Ovis canadensis), mule deer (Odocoileus hemionus), and pronghorn antelope (Antilocapra americana) between 1967–1970 and 1986–1988, a period when total ungulate numbers nearly tripled on Yellowstone's northern range. Ungulate species ratios on Yellowstone's northern winter range during the latter period were 100 elk : 10 mule deer : 3 bison : 2 pronghorns : 1 bighorns. Elk numbers were positively correlated to bison, mule deer, and pronghorn numbers (r2 = 0.76, 0.97, and 0.48, respectively, P < 0.01). Few other changes in habitat use or habitat overlap occurred, and diets for only 2 of the 10 species pairs, elk-bighorn (Spearman's rank order coefficient (RHO) = 0.55, P < 0.05) and mule deer – pronghorn (RHO = 0.64, P < 0.05), were significantly associated with each other. Bison consumed more grass and fewer sedges, mule deer more fringed sage (Artemisia frigida) and more rabbit-brush (Chrysothamnus spp.), and bighorn sheep more grasses and fewer sedges, while pronghorns ate less saltsage (Atriplex nuttalli) but more big sagebrush (Artemisia tridentata) during 1986–1988 than during 1967–1970. Bison expanded their range and bison and bighorn sheep used a wider variety of habitats. We found little evidence of change in competitive interactions between ungulate species. A few diet and habitat overlaps increased, the opposite of the prediction from the competitive exclusion principle amongst species, suggesting that intraspecific competition was more important. Several explanations are proposed for the lack of changes in niche relationships during a period of near tripling in density of the ungulate guild.

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Comparative health assessment of urban and non-urban free-ranging mule deer (Odocoileus hemionus) in southeastern British Columbia, Canada

PeerJ ◽

10.7717/peerj.4968 ◽

2018 ◽

Vol 6 ◽

pp. e4968 ◽

Cited By ~ 1

Author(s):

Amélie Mathieu ◽

Mark Flint ◽

Patrick M. Stent ◽

Helen M. Schwantje ◽

Thomas E. Wittum

Keyword(s):

British Columbia ◽

Body Condition ◽

Health Risks ◽

Mule Deer ◽

Odocoileus Hemionus ◽

Pregnancy Rates ◽

Hemorrhagic Disease ◽

Free Ranging ◽

Pathogen Exposure ◽

Body Condition Scores

Background The provincial wildlife management agency, British Columbia Ministry of Forests, Lands, Natural Resource Operations and Rural Development, performed a translocation to control the urban mule deer (Odocoileus hemionus; uMD) overpopulation and supplement the declining non-urban mule deer (nuMD) population in the Kootenay region, British Columbia, Canada. The objectives of this cross-sectional study were to evaluate the health of the urban and nuMD populations by comparing pathogen exposure, body condition scores (BCS) and pregnancy rates, to characterize the health risks associated with the translocation and to investigate the role of infectious diseases in the decline of the nuMD deer population. Methods Two hundred free-ranging mule deer were captured in urban and non-urban environments in the Kootenay region from 2014 to 2017. BCS and morphometric examinations were performed for each deer. Blood samples collected from each deer were tested for exposure to selected pathogens and pregnancy status. Results Body condition scores averaged 3.4 on a five-point scale, was greater in nuMD, and significantly differed between years. Antibodies were detected for adenovirus hemorrhagic disease virus (38.4% (uMD 43.7%, nuMD 33.3%)), bluetongue virus (0.6% (uMD 1.2%, nuMD 0%)), bovine respiratory syncytial virus (8.4% (uMD 4.6%, nuMD 12.1%)), bovine viral diarrhea virus (1.1% (uMD 0%, nuMD 2.2%)), bovine parainfluenza-3 virus (27.0% (uMD 27.6%, nuMD 26.4%)), Neospora caninum (22.1% (uMD 24.4%, nuMD 19.7%)) and Toxoplasma gondii (8.2% (uMD 12.3%, nuMD 3.9%)). No antibodies against epizootic hemorrhagic disease virus were detected. Pregnancy rates did not differ between the two deer populations (90.7% (uMD 90.6%, nuMD 90.9%)). Exposure to N. caninum was associated with a reduced probability of being pregnant. uMD were more likely to be exposed to T. gondii than nuMD. Discussion Comparison of BCS, pregnancy rates and pathogen exposure of uMD and nuMD showed that the health of the two populations did not significantly differ, suggesting uMD translocations do not pose a severe risk of pathogen transmission between mule deer populations and that these selected pathogens do not factor in the decline of the nuMD population. However, inclusion of additional health indicators and creation of a robust predictive disease model are warranted to further characterize the health of mule deer and the health risks associated with uMD translocations. These results should be considered as part of a formal risk assessment for future uMD translocations in southeastern British Columbia.

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Year-round water management for desert bighorn sheep corresponds with visits by predators not bighorn sheep

PLoS ONE ◽

10.1371/journal.pone.0241131 ◽

2020 ◽

Vol 15 (11) ◽

pp. e0241131

Author(s):

Grant M. Harris ◽

David R. Stewart ◽

David Brown ◽

Lacrecia Johnson ◽

Jim Sanderson ◽

...

Keyword(s):

Water Management ◽

United States ◽

Arid Regions ◽

Puma Concolor ◽

Mule Deer ◽

Bighorn Sheep ◽

Maximum Temperature ◽

Desert Bighorn Sheep ◽

Mountain Lions ◽

Southwest United States

Managing water (e.g., catchments) to increase the abundance and distribution of game is popular in arid regions, especially throughout the southwest United States, where biologists often manage water year-round for desert bighorn sheep (Ovis canadensis nelsoni). Bighorn may visit water when predators (e.g., mountain lions [Puma concolor], coyotes [Canis latrans]) do not, suggesting that differences in species ecology or their surface water requirements influence visit timing. Alternatively, visits by desert bighorn sheep and predators may align. The former outcome identifies opportunities to improve water management by providing water when desert bighorn sheep visit most, which hypothetically may reduce predator presence, range expansion and predation, thereby supporting objectives to increase sheep abundances. Since advancing water management hinges on understanding the patterns of species visits, we identified when these three species and mule deer (Odocoileus hemionus) visited managed waters in three North American deserts (Chihuahuan, Sonoran, Mojave). We unraveled the ecological basis describing why visits occurred by associating species visits with four weather variables using multi-site, multi-species models within a Bayesian hierarchical framework (3.4 million images; 105 locations; 7/2009-12/2016). Desert bighorn sheep concentrated visits to water within 4–5 contiguous months. Mountain lions visited water essentially year-round within all deserts. Higher maximum temperature influenced visits to water, especially for desert bighorn sheep. Less long-term precipitation (prior 6-week total) raised visits for all species, and influenced mountain lion visits 3–20 times more than mule deer and 3–37 times more than sheep visits. Visits to water by prey were inconsistent predictors of visits to water by mountain lions. Our results suggest improvements to water management by aligning water provision with the patterns and ecological explanations of desert bighorn sheep visits. We exemplify a scientific approach to water management for enhancing stewardship of desert mammals, be it the southwest United States or arid regions elsewhere.

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Depredación del borrego Ovis canadensis (Artiodactila: Bovidae) y el venado bura Odocoileus hemionus (Artiodactila: Cervidae) por Puma concolor (Carnivora: Felidae) en Coahuila, México

Revista de Biología Tropical ◽

10.15517/rbt.v66i4.32247 ◽

2018 ◽

Vol 66 (4) ◽

pp. 1496

Author(s):

Hugo Sotelo-Gallardo ◽

Juan Antonio García-Salas ◽

Armando Jesús Contreras-Balderas

Keyword(s):

Survival Rate ◽

Puma Concolor ◽

Mule Deer ◽

Bighorn Sheep ◽

Conservation Strategies ◽

Isolated Populations ◽

Mountain Lion ◽

Significant Difference ◽

The Impact ◽

Predation Rates

Small and isolated populations of bighorn sheep (subject to special protection according to NOM-059-SEMARNAT-2010) are vulnerable to predation by mountain lion in habitat sympatric with mule deer. Understanding the specific causes of death and survival is important for the development of conservation strategies for bighorn sheep and other ungulates that share the same habitat, such as mule deer.We evaluated and compared the rate of predation by puma in 12 bighorn sheep (10 females, two males) and 10 adult females of mule deer with radio collars through measure risk program (micromorts). The impact of predation in both populations of herbivores is evaluated through the estimation of densities of sheep and mule deer. 88 % (8/9) deaths by puma in bighorn sheep with an average monthly survival rate of 0.79 and predation rates due to puma range from 0.17 to 0.30. In mule deer predation due to puma was 83 % (5/6) with an average monthly survival rate of 0.86 and predation rates due to puma range from 0.10 to 0.25, however when comparing the mountain lion depredation rate we found a significant difference between species (Z = 1.826, df = 6, P = 0.05). The density in mule deer was 9x more that bighorn. The bighorn sheep being the prey most selected and the one most affected as the population with the lowest density.

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