Meeuwig said he doesn't have all the answers about potential competition between lake trout and native bull trout, but both are top-level predators and grow to similar sizes. Bull trout are getting "pinched" by downstream threats like lake trout and upstream threats such as reduced runoff from glaciers.
To study Glacier's fish, Meeuwig spent the summers of 2004 through 2006 in the park. He camped in the back country and floated across mountain lakes in innertubes and kayaks. Together with one or two technicians per year, he hiked to 17 lakes on the west side of the park. In addition to the previously-mentioned lakes, they counted fish and collected samples in Akokala Lake, Arrow Lake, Cerulean Lake, Lake Isabel, Lincoln Lake, Middle Quartz Lake, Trout Lake, Upper Kintla Lake and Upper Lake Isabel.
To get to those lakes, Meeuwig and his team stumbled through streams, bushwhacked their way through the back country, carried loads of equipment, and endured snow and cold. Some of the lakes were so remote that they had never been sampled before and had no trails to them.
"It's a tremendous amount of work," Guy said. "The reason we didn't have a data set like this before is because of all that hard work.
The Glacier National Park study had two purposes, Guy said. One was to develop management recommendations for the park, which Guy and Meeuwig presented to park managers in January. Besides maintaining natural barriers, they suggested establishing a sampling program that would allow scientists to document changes in the bull trout populations.
The second goal of the Glacier study was to advance the scientific knowledge regarding the interaction between the park's landscape and bull trout population genetics. This will be covered in Meeuwig's doctoral dissertation.
|Contact: Evelyn Boswell|
Montana State University