Evaluation of an Augmentation of Rocky Mountain Bighorn Sheep at Badlands National Park, South Dakota

<p>Audubon’s (a.k.a. Badlands) bighorn (Ovis canadensis auduboni [Merriam 1901] now O. c. Canadensis [Shaw 1804]), described as a subspecies of bighorn sheep, was extirpated from its range by 1924. In 1964, 22 Rocky Mountain bighorn sheep were translocated from Pikes Peak, Colorado, to Badlands National Park (BNP) in southwestern South Dakota. Based on the estimated effective population size and analysis of molecular data, the bighorn sheep population at BNP underwent a population bottleneck at founding. Recommendations to restore genetic diversity in the BNP population included a mixed-sex augmentation (n > 30) from an outbred, native population of Rocky Mountain bighorn sheep. Shackleton and the International Union for Conservation of Nature and Natural Resources (IUCN)/Species Survival Commission (SCC) Caprinae Specialist Group also had identified the population at BNP as a population of conservation concern and recommended expanding population size and distribution of bighorn sheep throughout their range in the eastern mixed-grass prairie. In September 2004, BNP in conjunction with the South Dakota Department of Game, Fish and Parks and the New Mexico Department of Game and Fish, captured, radio-collared or ear-tagged, and relocated to BNP 23 (10 adult ewes, 2 yearling ewes, 5 ewe lambs, and 6 ram lambs) Rocky Mountain bighorn sheep from Wheeler Peak, New Mexico. Because of the poor colonizing ability of bighorn sheep, previous transplant programs have attempted to reestablish populations in localized areas where they have been extirpated or to expand populations where they have been reduced. All western states in North American have reintroduced populations of bighorn sheep, yet the rate of successful establishment of self-sustaining reintroduced populations has been < 50%. If introduced bighorn sheep were monitored regularly and if each introduction was viewed as an experiment and rigorously evaluated, the rate of successful translocations may increase. The overall objective of this study was to evaluate the success of the augmentation by examining 1) survivorship, 2) lamb production, 3) dispersal, 4) 95% and 50% adaptive kernel, fixed kernel, and minimum convex polygon home-range size, 5) 95% and 50% adaptive kernel planimetric and surface area estimates, 6) interannual variation in home-range size, 7) habitat use, 8) escape terrain and buffer terrain, 9) an animal location based model (ALBM), 10) an escape terrain and buffer model (ETBM), 11) the habitat evaluation procedure (HEP) of Sweanor et al. (1995) and Zimmerman et al. (2006), 12) degree of population subdivision (Fst) between the North and South Units in BNP, 13) observed heterozygosity (Ho), expected heterozygosity (He), number of alleles per locus, average number of alleles per locus (Ne), and the number of effective alleles (Nea) of bighorn sheep at BNP pre- and post-augmentation. Radio-collared individuals were relocated ≥ 3 times weekly from September 2004–2007. Visual daytime locations were recorded and added to a Geographic Information System. Genomic DNA from blood and tissue samples from resident and translocated bighorn sheep and their offspring was extracted, amplified, and typed for 15 microsatellite loci. Eighteen of 23 translocated bighorn sheep survived and remained with the subpopulation. In 2005, 10 lambs were born and 9 (5 females, 4 males) survived to 1 year of age. In 2006, 9 lambs were born and 8 (4 females, 4 males) survived to 1 year of age. In 2007, 8 lambs were born and 7 (5 females, 2 males) survived to 1 year of age. In 2006, 9 yearling first-generation offspring (F1) dispersed from BNP with straight-line dispersal distances ranging from 43 to 524 km. In 2007, 3 yearling male F1 dispersed 25 km from BNP. The 95% adaptive and fixed kernel home-range estimates did not differ (P = 0.096) and the 95% adaptive kernel home-range estimate and the minimum convex polygon estimate did not differ (P = 0.211). The 50% fixed kernel home-range estimate was greater (P = 0.001) than the 50% adaptive kernel home-range estimate. The 95% home-range size increased (P = 0.007) between year 1 of the study and year 2 of the study, but the core estimates did not differ (P = 0.450) between years. The 95% and 50% 3D surface areas of translocated sheep were greater (P = 0.001; P = 0.001, respectively) than the 2D planimetric areas; the 95% and 50% surface area estimates of the resident bighorns were greater (P = 0.027; P = 0.027, respectively) than planimetric areas. The 95% and 50% planimetric adaptive kernel estimates were greater (P = 0.002; P = 0.002, respectively) in resident than translocated sheep.</p>

Name thesis:degree_name

Doctor of Philosophy (PhD)

Level thesis:degree_level

Dissertation - Open Access

Discipline thesis:degree_discipline

Wildlife and Fisheries Science

Year

2008

Author dc:creator

• Zimmerman, Teresa J.

Contributors dc:contributor

• Jonathan A. Jenks

• Natural Resources and Conservation

Statement dc:rights

• Copyright © 2008 Teresa J. Zimmerman. All rights reserved.

Language dc:language

en

Repository record dc:identifier

https://openprairie.sdstate.edu/etd/611

OAI identifier oai:identifier

oai:openprairie.sdstate.edu:etd-1611