2007-08 Winter Count of Northern Yellowstone Elk
Contact: PJ White, NPS, 307-344-2442
Contact: Tom Lemke, MT FW&P, 406-222-0102
Contact: Dan Tyers, USFS, 406-848-7375
February 25, 2008
Montana Department of Fish, Wildlife, & Parks (contact: Tom Lemke, 406/222-0102)
2007-08 WINTER COUNT OF NORTHERN YELLOWSTONE ELK
The Northern Yellowstone Cooperative Wildlife Working Group conducted its annual winter survey of the northern Yellowstone elk population on February 14, 2008. A total of 6,279 elk were counted during good survey conditions. Approximately one-third of the observed elk were located within Yellowstone National Park, and two-thirds were located north of the park boundary. Biologists used four fixed-wing aircraft to count elk through the entire northern range during the one-day survey. The northern Yellowstone elk herd winters between the northeast entrance of Yellowstone National Park and Dome Mountain/Dailey Lake in the Paradise Valley.
This year’s count of 6,279 elk was similar to the counts of 6,588 elk in winter 2006 and 6,738 elk in winter 2007, but substantially lower than the 9,545 elk counted in winter 2005. “This decrease in counted elk likely reflects the continuing effects of predation by wolves and other large carnivores and, possibly, some effects from the severe, long-term drought on maternal condition and recruitment,” according to P.J. White, biologist for Yellowstone National Park.
“It also appears that elk distribution has changed in recent years with elk numbers north of Yellowstone Park leveling off at between 3,200-4,000 elk, while elk numbers wintering inside the park appear to be decreasing,” according to Tom Lemke, biologist for Montana Fish, Wildlife, and Parks. As a result, in recent years over 50% of the counted population has wintered north of Yellowstone National Park. Winter range north of the park occurs at lower elevation and tends to have better forage availability, less snow, and milder environmental conditions. Another possible factor influencing winter elk distribution is wolf distribution. Winter wolf densities are considerably lower on winter ranges north of the park compared to winter ranges inside the park. “Elk may be using several factors, including the presence of wolves, in selecting where they spend the critical winter months. If current trends continue, then the long-term importance of elk habitat north of the park will only increase,” Lemke added.
The State Elk Plan calls for a winter population objective of 3,000-5,000 elk north of Yellowstone with 2,000-3,000 of those animals wintering on or near the state-owned Dome Mountain Wildlife Management Area. In the last six years, an estimated total of 3,200-4,000 elk have wintered north of Yellowstone National Park with 2,100-3,000 elk wintering on or near the Dome Mountain Wildlife Management Area. By the end of this winter, biologists expect elk numbers north of the park to remain within the management objectives. In contrast, during the late 1990s, 5,300-8,600 elk wintered north of the park with 3,500-4,500 elk in the Dome Mountain area. Wintering such large numbers of elk could lead to long-term habitat decline and increase the likelihood of game damage problems on private land.
“From a winter elk management perspective we are currently meeting State Elk Plan population objectives,” Lemke said. “However, elk recruitment remains below desirable levels.” To help address elk recruitment issues, Montana Fish, Wildlife, and Parks dramatically reduced the antlerless elk harvest to an average of less than 75 cows and calves harvested each year during the last three years. “Hunting has basically been removed as a significant factor regulating northern Yellowstone elk numbers,” said Lemke. Late winter recruitment rates have made modest gains in the last two years to 19-24 calves per 100 cows compared to 12-14 calves per 100 cows the previous four years. Elk recruitment objectives for this population are 20-30 calves per 100 cows. This year’s recruitment rate will be determined during aerial surveys conducted in March. “It is unlikely that we will see any significant increase in elk numbers until there is a long-term improvement in recruitment rates,” Lemke added.
The Working Group will continue to monitor trends of the northern Yellowstone elk population and evaluate the relative contribution of various components of mortality, including predation, environmental factors, and hunting. The Working Group was formed in 1974 to cooperatively preserve and protect the long-term integrity of the northern Yellowstone winter range for wildlife species by increasing our scientific knowledge of the species and their habitats, promoting prudent land management activities, and encouraging an interagency approach to answering questions and solving problems. The Working Group is comprised of resource managers and biologists from the Montana Fish, Wildlife, & Parks, National Park Service (Yellowstone National Park), U.S. Forest Service (Gallatin National Forest), and U.S. Geological Survey-Northern Rocky Mountain Science Center, Bozeman.