From the North Dakota Game and Fish Department
-- Based on observations during the annual bighorn sheep survey, biologists believe North Dakota’s tough winter didn’t significantly harm the state’s bighorn sheep population. In fact, statistics show the population likely increased from last year.
Brett Wiedmann, big game biologist, Dickinson, said lamb recruitment was at 35 percent, about average in North Dakota, but lamb survival was exceptional as 80 percent of lambs counted during summer survived the winter.
“Based upon the high number of recruited lambs observed in the population, we are optimistic that the adult segment of the state’s bighorn sheep population came through the winter in good shape as well,” Wiedmann said.
Each summer, typically in August, Game and Fish Department biologists count and classify all sheep. Biologists then recount lambs in March to determine lamb recruitment.
In all, biologists counted 313 bighorn sheep, 11 percent above 2007 and 35 percent higher than the five-year average. The northern badlands’ population was up 14 percent from last year, while the southern badlands’ population saw a 4 percent increase.
All total, 96 rams, 167 ewes and 50 lambs were counted – record highs for each.
A big impact on the health of the population can be attributed to the bighorn sheep that were transplanted from Montana in January 2006. “These robust sheep are doing amazingly well, in fact you can say they are thriving,” Wiedmann said. “All their lambs made it through this year’s tough winter unscathed.”
The only negative, according to Wiedmann, was the ram-to-ewe ratio was on the lower end, at about 57 rams per 100 ewes. “We would like to have that number between 60-70 rams per 100 ewes,” he said.
Wiedmann knows there was some winter mortality, especially in the northern badlands, but the extent won’t be known until the 2009 survey next summer. “The 2008 adult numbers do not reflect winter mortality,” Wiedmann added. “Consequently, just to be cautious, we reduced the number of hunting licenses available in 2009 from six to five.”