Palearctic predator invades North American Great Lakes

摘要: Bythotrephes cederstroemii Schoedler, a predatory freshwater zooplankter (Crustacea: Cladocera), was first found in the Laurentian Great Lakes December 1984. The individuals were from Lake Huron, followed 1985 with records Erie and Ontario. By late August, 1986 species had spread to southern Michigan (43°N). has not previously been reported North America, but restricted northern central Palearctic distribution. Its dramatic widespread rise abundance greatest offshore regions. appears be invading aggressively, avoiding habitats presently occupied by glacio-marine relict that became established deep oligotrophic American lakes after Wisconsin glaciation. Because it is voracious predator its invasion may lead alterations native zooplankton fauna of Lakes. It offers chance study how plankton join an existing community. Judging persistence success European lakes, now become permanent member communities Nearctic.