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Spiny Water Flea

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Spiny water flea
Spiny waterflea, adults - Photo by Gary Montz
Scientific Name: 

Bythotrephes longimanus (Leydig, 1860) (ITIS)


Bythotrephes cederstroemi (Yan et al. 2011)

Common Name: 

Spiny water flea

Native To: 

Eurasia (Yan et al. 2011)

Date of U.S. Introduction: 

First discovered in Lake Huron in 1984; established in all of the Great Lakes by 1987 (Cullis 1988)

Means of Introduction: 

Most likely introduced through ballast water (Yan et al. 2011)


Has caused a decline in the population of zooplankton as a result of predation (Vanderploeg et al. 2002); may also compete with some native species, such as perch and small crustaceans (Branstrator and Lehman 1996)

Distribution / Maps / Survey Status

DOI. USGS. Wetland and Aquatic Research Center.
Provides detailed collection information as well as animated map.



Google. YouTube; North American Fishing Club. 

University of Minnesota. Minnesota Aquatic Invasive Species Research Center.

Selected Resources

The section below contains highly relevant resources for this species, organized by source. Or, to display all related content view all resources for Spiny Water Flea.

Council or Task Force

Alberta Invasive Species Council (Canada).

See also: Fact Sheets for more information about individual invasive species, including those listed as "Prohibited Noxious" and "Noxious" under the Alberta Weed Control Act

Aquatic Nuisance Species Task Force. Stop Aquatic Hitchhikers.

IUCN. Species Survival Commission. Invasive Species Specialist Group.

Ontario's Invading Species Awareness Program (Canada).

Northeast Aquatic Nuisance Species Panel.

New York Invasive Species Clearinghouse.

St. Lawrence - Eastern Lake Ontario Partnership For Regional Invasive Species Management (New York).

Texas State University System. Texas Invasive Species Institute.
Federal Government
DOI. USGS. Wetland and Aquatic Research Center.
Provides distribution maps and collection information (State and County).
State and Local Government

New York Department of Environmental Conservation.

Minnesota Department of Natural Resources.

Wisconsin Department of Natural Resources.

Massachusetts Department of Conservation and Recreation.
See also: Invasive Species Information for more resources

University of Minnesota. Minnesota Aquatic Invasive Species Research Center.

Pennsylvania State University. Pennsylvania Sea Grant.
See also: Aquatic Invasive Species: Resources for additional species information
University of Wisconsin Sea Grant.
Paul Smith's College (New York). Adirondack Watershed Institute.
Lake George Association (New York).

Invasive Species Centre (Ontario).