# New Crustacean Invader Found In The Great Lakes



## Hamilton Reef (Jan 20, 2000)

New Crustacean Invader Found In The Great Lakes
http://www.iaglr.org/jglr/release/31/31_3_333-342.php

FOR IMMEDIATE RELEASE
September 2, 2005

New Crustacean Invader Found In The Great Lakes

Ann Arbor, Mich.  The Great Lakes are home to yet another invasive organism - the sideswimmer Gammarus tigrinus. The eventual arrival of this species was predicted by Igor A. Grigorovich and fellow researchers a few years ago. The shrimp-like crustacean, native to the Atlantic coast of North America, is a notorious invader in European waters where it has been aggressively eliminating native crustacean species. H.B. Noel Hynes of the University of Liverpool believes that Gammarus tigrinus was first " introduced into Northern Ireland from North America during WWI by American troops, whence it crossed the Irish Sea as ballast, to the Liverpool/Chester area."

First identified in samples collected from Saginaw Bay, Lake Huron in 2003, Gammarus tigrinus was subsequently identified in samples collected from other shallow, coastline habitats in all five of the Great Lakes dating back to 2001. Grigorovich and fellow researchers of the University of Windsor discovered that the new invader was the second most abundant sideswimmer in cattail (Typha) beds of lower Great Lakes coastal wetlands. As with the European introduction, Gammarus tigrinus likely entered the Great Lakes with the help of humans. 

Previous studies implied that Gammarus tigrinus can't reproduce in freshwater. However, Dr. Grigorovich and his colleagues observed reproducing individuals and egg-carrying females, indicating that the species has become established and will likely remain a permanent member of the Great Lakes benthic community. 

Original Publication Information
Results of this study "Colonization of the Laurentian Great Lakes by the Amphipod Gammarus tigrinus, a Native of the North American Atlantic Coast," are reported by Igor A. Grigorovich, Misun Kang and Jan J.H. Ciborowski in the latest issue (Volume 31, No. 3, pp. 333-342) of the Journal of Great Lakes Research, published by the International Association for Great Lakes Research, 2005.

Contacts
For more information about the study, contact A. Grigorovich, 320 Dixon Road, Suite 1016, Toronto, ON, M9R 1S8, Canada; [email protected]; (416) 241-6624.

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; [email protected]; (608) 692-1076.

Links
The Article (abstract) 
Vol. 31(3) Table of Contents 
Searchable JGLR Archive 
IAGLR Web Site


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