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Spiny Water Flea

Scientific Name

Bythotrephes longimanus (Leydig, 1860) (ITIS)

Common Name

Spiny water flea


Bythotrephes cederstroemi (Yan et al. 2011)

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)

Spiny water flea

Spiny waterflea, adults


Photo by Gary Montz

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Distribution / Maps / Survey Status


Selected Resources

The section below contains highly relevant resources for this species, organized by source.

Council or Task Force
Federal Government
State and Local Government