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(Page 2 of 2)
North of Rising Wolf Mountain is one of the park's historic tourist hubs, called Many Glacier. Four valleys laced with glaciers and alpine lakes come together here. Bighorns are common in this part of the park, and wildlife biologists have studied them here since the 1920s. Nobody had ever reported sheep wintering on Mount Allen, a large buttress on the main valley's south side. Yet that's where collars tracked wintering bighorns. GPS points also debunked a long-held belief that bighorn on adjacent slopes constituted a single herd; instead, sheep stay in separate herds throughout the year. Keating laughs: more than eight decades of bighorn research in Many Glacier has been overturned by fist-size GPS units.
He and geneticist Gordon Luikart of the University of Montana are getting even more bighorn insights from DNA samples. For instance, a preliminary study suggests that two populations living only 25 miles apart—one in Many Glacier and the other in Two Medicine—have surprisingly different genes. The contrast is "approximately the difference you would observe between Asians and Europeans. So it's a very large difference for such a small distance." Keating says it's possible the herds haven't mingled much since the last ice age ended more than 10,000 years ago.
Such isolation might protect the animals. In the 1980s, an outbreak of pneumonia wiped out 65 percent of southern Alberta's bighorn sheep and infected Many Glacier's population. But the Two Medicine herd was spared.
Six months after i watched Keating and his crew collar sheep, we met again below Rising Wolf Mountain on a gusty day in May. We hiked up the purple pasqueflower-lined trail, listening to beeping radio signals picked up by three telemetry antennas. "Glacier is one of the worst places for radio tracking," Keating said, turning in a slow circle with an antenna overhead. "The mountainous terrain ricochets signals off cliffs, sending a strong beep from both the collar's location and its opposite direction." Our primary goal was to find six collars, most of which had been programmed to fall off two days earlier.
Our other task was to collect feces from ewe 118, the one we had collared in the fall. Hormone levels in fecal samples, which Keating sends to the National Zoo for analysis, indicate whether a ewe is pregnant. By combining this information with field observations of birth rate and survival rate, Keating can predict the herd's population growth. Ewe 118 was browsing on a steep hillside amid 40 sheep still in their white winter coats. Schmitz and another researcher pursued her across snow, ridges and cliffs. We wouldn't see them again for eight hours.
The rest of us followed well-worn sheep paths uphill—scrambling over rocks, slipping on pebbly scree. We were in prime bighorn territory, and collar 568 lay in plain sight on the rocks. Another collar was buried beneath early winter snows. Keating donned crampons and grabbed an ice ax to ascend a small, steep couloir, and dug it out.
As we trekked out along the muddy trail, sun glinted off Rising Wolf's snow-packed gullies. After 11 hours of hiking in Glacier's moody weather, we'd collected one ewe's scat, counted 84 bighorns and found four of six collars. Keating's pack cradled thousands more bighorn location points full of surprises.
Becky Lomax is the author of Moon Handbooks: Glacier National Park and was a hiking guide in the park for 10 years.
Comments
Kudos to these folks who are so dedicated! I lived in SD for many years and traveled on several occasions to Glacier Park and surrounding areas. We had a few Bighorn Sheep in the Black Hills (South Dakota) also. They are just fascinating to watch, especially if you can observe them for more than a few minutes. Watching the little ones climb is wonderous. They bounce up the rocks like they had springs attached to their hooves. Keep up the great work and thank you!
Posted by C. M. Meyer on March 3,2008 | 05:34AM