Impacts on Trout Populations Topic Of Discussion

June 30, 2003 -- Conditions that may be harmful to Rocky Mountain trout populations will be discussed during a free public presentation Thursday, July 3, at the University of Wyoming-National Park Service (UW-NPS) Research Center, located at the AMK Ranch in Grand Teton National Park.

The presentation begins at 7 p.m. at the AMK Ranch, north of Leeks Marina. A barbecue will be held at 5:30 with a $5 per person contribution suggested. To make reservations for the barbecue, call the UW-NPS Center at (307) 543-2463.

Wayne Hubert, director of fisheries research with the Wyoming Cooperative Fish and Wildlife Research Unit in the UW Department of Zoology and Physiology, will be the speaker. He says winter is a dominant season in the northern Rockies and is believed to be a time of stress for trout in rivers and streams.

"Trout have evolved behaviors to survive well in rivers and streams that are not highly modified by humans. However, in regulated streams downstream from large reservoirs, the situation differs markedly," Hubert says. "Here, a lack of surface ice, lack of available food, frazil-ice and anchor-ice formation during cold weather, and variation in discharge from upstream reservoirs can combine to affect trout, with the smallest fish the most severely affected."

The UW-NPS Research Center provides a base for university faculty members and governmental scientists from throughout North America to conduct research in the diverse aquatic and terrestrial environments of Grand Teton National Park and the Greater Yellowstone Ecosystem.

Posted on Monday, June 30, 2003