Bighorn sheep population stays steady
Most everyone who hunts in North Dakota, whether they actually hunt deer or not, knows the opening day for deer gun season is Friday, Nov. 8.
I'd also venture to guess that unless you were one of the four hunters who have a North Dakota bighorn sheep license for this fall, or if you are a friend or family member of one of those hunters, you probably didn't know for sure that the state's bighorn sheep gun season opens Friday.
Three of those hunters were lucky enough to draw a once-in-a-lifetime tag in the lottery, while the fourth was the successful bidder for North Dakota's Wild Sheep Foundation auction license.
Heading into the 2013 season, the state's sheep population is holding steady. Results from this summer's survey indicated a minimum of 299 bighorn sheep, which is the same as last year and only 17 percent below a record summer count observed in 2008.
Brett Weidmann, a North Dakota Game and Fish Department big game biologist, said the female segment of the population remained stable, but the agency is concerned about a decline in the number of rams, which was 11 percent below last year and 21 percent below the record observed in 2009.
"Annual survival of adult rams is typically very high," Weidmann said, "so we need to figure out why our ram population is continuing to decline despite reductions in hunting licenses."
Survey results revealed 79 total rams, 155 ewes and 65 lambs. A record 258 of those sheep, seven more than last year, were counted in the northern Badlands. The count was 41 in the southern Badlands, seven fewer than last year.
"Bighorn sheep numbers increased again in the northern Badlands but continue to struggle south of the Interstate," Weidmann said, noting that a record 64 lambs were observed in the north, but only one in the south. "However, despite poor results in the southern Badlands, the total number of lambs observed this summer surpassed the previous record of 60 in 2008."
Annual bighorn sheep survey statistics are not recorded using a calendar year, but instead are done over a 12-month period beginning each April and ending the following March. Each summer, Game and Fish Department biologists count and classify all bighorn sheep, a process that takes nearly six weeks to complete as biologists locate each bighorn herd in the badlands by tracking radio-marked animals from an airplane, and then hike into each group to record demographic data using a spotting scope and binoculars.
Biologists then complete the annual survey by recounting lambs in March to determine lamb recruitment, or lambs that survive the first winter.
While the bighorn population is not large, and may never grow to more than a few hundred animals, they attract considerable interest. In 2013, 9,587 people applied for the three licenses available by lottery.
Though most people in the state have never seen one of these remarkable animals in the wild, they are a key part of what makes North Dakota's outdoors so unique and special.