By Mark Watson Black Hills Pioneer Jul 11, 2015
DEADWOOD — High on the steep slopes above Deadwood, two men working for the South Dakota Game, Fish and Parks are gathering information on the habitat and vegetation in the area the state’s newest bighorn sheep herd calls home.
On Feb. 12, 26 bighorn sheep from Canada were released in the hills above Deadwood in the Grizzly Gulch Fire burn area picked for its habitat.
“The habitat that is best for bighorn sheep is rugged terrain with a lot of slope,” said John Kanta, regional wildlife manager with the GF&P during the release. “Basically, cut down all the trees and light it on fire. So with the Grizzly Gulch Fire of 2002, that essentially took care of the job for us and made really nice bighorn sheep habitat.”
Now, after four months of tracking the sheep via their radio collars, a new phase of monitoring the sheep is beginning.
Ty Werdel, a South Dakota State University graduate student who will follow the animals for the next year and a half; and Jason Clark, a technician with the GF&P, are collecting data on survival, the specific causes of mortality, habitat selection and habitat quality.
On Wednesday, the two were hiking in thigh-burning terrain to a point where the bighorns were spotted the week before.
Data collected included: degree of slope, 30 degrees on this particular hillside that could serve as a breathtaking sled hill in the winter; distance from escape terrain, about 60 yards; and level of woody substance, almost none.
“This is very typical terrain for bighorn sheep,” Werdel said. “Good escape routes, steep slope, good forage, and no trees.”
The two also measured the height and the density of the vegetation to include percentage of grasses and shrubs. They then clipped the vegetation from a 2-foot diameter area and placed the greenery in a bag. Those clippings will be dried and weighed to help determine a total biomass.
“We note the species (of vegetation), but we are mostly interested in weight. Bighorns will eat mostly anything,” Clark said.
The herd has grown since the February release. At least 13 ewes have lambs, and there is a possibility of eight others. Werdel said he has not gotten close enough to the other ewes yet to see if they too had lambs. He noted that the bighorn sheep have only a single lamb at a time, and that it is very rare for them to have twins.
Two ewes have died. One died shortly after the release due to injuries or the stress from the Canadian capture operation or the long drive south. The other ewe died for unknown reasons in a creek bottom not far from the slope the two were sampling.
“We don’t really know what happened to her,” Werdel said. “We found her and took a bunch of samples and sent them to a lab. All those came back negative.”
The older of the two rams brought from Canada also died. He was euthanized on July 6.
The 3-year-old ram came into contact with domestic sheep near St. Onge, and department policy is to euthanize wild sheep that do so to prevent the spread of a pasteurella bacteria that cause pneumonia and decimates the wild herds. It is also a common policy among other states’ wildlife agencies as the bacteria-induced pneumonia die-offs have been noted in multiple Western states.
Werdel said older rams are known to leave the ewes after lambing season, but wildlife officials had hoped that he was young enough to stay with the herd. On July 2, Werdel said he located a signal from the ram’s radio collar in the Deadwood area. That night, someone in the St. Onge area notified the GF&P that the ram was in thevicinity. The male headed back toward Deadwood and traveled through Spearfish in the Exit 14 area. It was spotted in the Culvers’ parking lot, and in the Green Acres subdivision before returning to Deadwood.
It wasn’t the first time the sheep have left the area.
Shortly after they were released, they wandered from the Hannah Campground area up Spearfish Canyon, to Custer Peak, and on Lookout Mountain. One even ventured down Main Street Deadwood.
Other than the loss of three animals, Werdel said, the herd is looking well and have become a popular attraction to area residents.