Park sheep study shows they have a unique social life

Hungry Horse News

A study of Glacier National Park's sheep is slowly revealing the secret side to the majestic animals' lives-a life that includes plenty of movement, especially if one is a ram.

Bighorn rams are known to travel from Many Glacier to Waterton and from the south shore of St. Mary Lake all the way to Marias Pass, researcher Kim Keating said in a recent interview.

The study, which is headed up by Keating and other U.S. Geological Survey staffers, will continue through this summer and next.

Currently there are 28 sheep equipped with special GPS radio collars in the park. The collars record their movements and store the data. The collars are then programmed to fall off. They emit a tracking signal, and then are picked up by researchers.

So far, the data is showing some interesting trends among sheep.

For one, the ewes in particular seem to form socially distinct groups. For example, Keating said, ewes from Mount Altyn in the Many Glacier Valley are socially distinct from ewes from Mount Henkel, even though the mountains are joined together with no large barriers.

Sheep also aren't afraid to travel to get to salt licks. One ewe with a lamb traveled from Altyn to a salt lick near Yellow Mountain to the north and back in about a day. That's 11 to 12 air miles and about twice that by foot. More impressive was the lamb was just a few days old. Sheep, like the park's mountain goats, utilize mineral licks in the spring after coming off winter forage.

"They're hitting salt licks pretty heavily," Keating noted. "It's a pretty powerful attractant."

Sheep also set up socially distinct populations in the summer time as well.

Bighorn rams congregate together in one area, while ewes will congregate in another.

Throughout the summer, there is virtually no intermingling of the two until the fall, when the rut begins.

The study is ultimately designed to look at fire regimes and their impact on sheep habitat in the park. Researchers know, for example, that the lack of fire in some areas has resulted in more trees than what would normally be there.

But this study is still a ways from taking all the data and merging it together, Keating noted. So far, three collared sheep have died apparently of natural causes. It's hard to tell the exact cause of death because, in all three cases, either grizzly bears or other scavengers found the carcass fairly quickly and ate them.