FOR IMMEDIATE RELEASE

January 3, 2008

Contacts

First exotic zooplankton species invaded Lake of the Woods in 1990s!

Ann Arbor, MI — Cores of lake bottom sediments can give us clues about what happened in a lake decades ago even when no one was collecting water samples or suspected that any new species were invading our lakes.

Many aquatic organisms leave fossil remains in the bottom sediment that can tell researchers who lived in lakes years ago. In Lake of the Woods (LOW), a large inland lake spanning the Canada-U.S. border between Ontario and Minnesota, non-native species of aquatic organisms are beginning to establish themselves, spreading from the Laurentian Great Lakes. Eubosmina coregoni is the first species we have been able to detect in the lake sediments that date back to the 1990s.

"Eubosmina coregoni is only the first of many non-native species that will likely invade LOW in the next few years,", says Brenda Hann, a Professor at the University of Manitoba. "By studying the bottom sediments and their microfossils, we can learn when new species invaded a lake and determine if they caused changes in the rest of the aquatic food web."

Only the timing of appearance of this non-native species in LOW can be discovered from lake sediments, not the pathway of invasion. We looked at many cores from many areas of this complex lake to find where it was most common in hopes this would tell us more about where and how the species invaded. Because of the heavy use of this lake for recreation and commercial fishing, it is likely that humans assisted in its invasion and spread in the lake.

Original Publication Information

Results of this study, "Using Microfossil Remains in Lake Sediments to Examine the Invasion of Eubosmina coregoni (Cladocera, Bosminidae) in Lake of the Woods, Ontario, Canada," are reported by Karyn D. Suchy and Brenda J. Hann in the latest issue (Volume 33, No. 4, pp. 867-874) 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 Brenda Hann, Department of Biological Sciences, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2, hann@cc.umanitoba.ca, (204) 474-7450.

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.