Smelt are the Preferred Diet of Lake Trout
Ann Arbor, MI — Lake trout in Lake Superior appear to prefer to eat rainbow smelt more than other fish.
There are two primary types of lake trout, the fat or siscowet lake trout and the lean lake trout. Both of these types have been increasing in number over the last 20 years and could be competing, which may slow the increase of the commercial and recreational important lean lake trout.Researchers from around Lake Superior collaborated to analyze 16 years of data to examine the food habits of the two types of lake trout, in order to observe if competition was occurring and if there had been any changes in the preference of food items. Rainbow smelt were preferentially eaten by lean lake trout, despite recent declines in smelt abundance. Further, although siscowet lake trout also appeared to prefer rainbow smelt, there is not strong evidence for competition among the two lake trout types.
"This work helps bring up-to-date information to management agencies around Lake Superior," said Bradley Ray, a former graduate student at the University of Minnesota-Duluth. "Showing the food habits of lean and siscowet lake trout can further the efforts to restore lake trout throughout the Great Lakes."
Original Publication Information
Results of this study "Diet and Prey Selection by Lake Superior Lake Trout during Spring, 1986–2001," are reported by Bradley A. Ray, Thomas R. Hrabik, Mark P. Ebener, Owen T. Gorman, Donald R. Schreiner, Stephen T. Schram, Shawn P. Sitar, William P. Mattes and Charles R. Bronte in the latest issue (Volume 33, No. 1, pp. 104-113) 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 Bradley Ray, College of Natural Resources, Virginia Tech University, Blacksburg, VA 24061, baray@vt.edu, (540) 231-5320.
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.