Lake trout are on the move

Ann Arbor, MI — Lake trout are on the move, but determining where the fish are going, and when, poses a challenge to fisheries managers who are restoring lake trout populations in the Great Lakes.

"Gauging fish movements out of areas where they are released helps managers determine the success of restoration programs and set regulations for recreational fisheries," says Sara Adlerstein, an assistant research scientist at the University of Michigan's School of Natural Resources and Environment.

To find answers, Adlerstein's scientific team investigated movements of tagged lake trout in the U.S. waters of Lake Huron by analyzing when and where the marked fish were recovered, and by whom. They obtained recovery reports from recreational fisheries, including charter-boat captains and collection specialists who keep track of fish catches, and used statistical models to standardize recoveries by these sources.

The researchers found that higher proportions of tagged lake trout moved out of release areas than was previously thought. They also reported that, contrary to current assumptions, the fish underwent movements among management areas during May through September. "These findings need to be considered for improving the current models used for lake trout management," Adlerstein concludes.

Original Publication Information

Results of this study "Lake Trout Movements in U.S. Waters of Lake Huron Interpreted from Coded Wire Tag Recoveries in Recreational Fisheries," are reported by Sara A. Adlerstein, Edward S. Rutherford, John A. Clevenger, James E. Johnson, David F. Clapp and Aaron P. Woldt in the latest issue (Volume 33, No. 1, pp. 186-201) of the Journal of Great Lakes Research, published by the International Association for Great Lakes Research, 2007.

Contacts

For more information about the study, contact Sara Adlerstein, School of Natural Resources and Environment, University of Michigan, Ann Arbor, MI 48109; adlerste@umich.edu; (734) 764-4491.

For information about the Journal of Great Lakes Research, contact Marlene Evans, Editor, National Water Research Institute, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, Canada; editor@iaglr.org; (608) 692-1076.

Links

Since 1967, IAGLR has served as the focal point for compiling and disseminating multidisciplinary knowledge on North America's Laurentian Great Lakes and other large lakes of the world and their watersheds. In part, IAGLR communicates this knowledge through publication of the Journal of Great Lakes Research, available to members in print and electronic form. A searchable archive of the journal is available online and includes the abstracts of articles from the journal's inception in 1975 through the most recent issue. In addition, complete articles are available to members who have signed up for an electronic subscription.