Researchers examine wolf effect on bighorns
by Cat Urbigkit, Pinedale Online!
June 11, 2008
A group of researchers is studying the effect of wolf reintroduction on bighorn sheep in Yellowstone National Park.
According to an abstract of a research paper recently published in the journal Wildlife Biology, "the presence of wolves did not prevent the bighorn sheep population from increasing slowly during the decade following reintroduction."
"However, sheep counts remain low compared to the 487 sheep observed before an outbreak of keratoconjunctivitis caused 60% mortality during 1982, suggesting that other factors limited the recovery of this relatively isolated, high-elevation, native sheep population. Increases in abundance and recruitment of bighorn sheep during 1998-2005 were concurrent with a 50% decrease in the numbers of northern Yellowstone elk after wolf reintroduction.
"Thus, the potential effects of decreased competition for resources between elk and bighorn sheep on lamb recruitment and sheep population growth merit further investigation."
The paper is called "Initial effects of reintroduced wolves Canis lupus on bighorn sheep Ovis canadensis dynamics in Yellowstone National Park," and was authored by P. White, T. Lemke, D. Tyers, and J. Fuller.