Red Mysid
In Lake Michigan, a newly discovered, invasive species of shrimp could compete with fish for zooplankton as a source of food. Scientists last month found thousands of red mysid, with the scientific name Hemimysis anomala, in the channel of Muskegon Lake, which empties into Lake Michigan Researchers at the National Oceanic and Atmospheric Administration’s Lake Michigan Field Station said the 1.3-centimetre-long shrimp were likely introduced to the Great Lakes through the ballast water of an oceangoing freighter. “It came from the Ponto-Caspian region, the same area that gave us zebra mussels, quagga mussels and the goby,” Steve Pothoven, a fisheries biologist with the NOAA, told The Muskegon Chronicle for a Friday story. It’s the first time the bloody red mysid has been spotted in North American waters, said Pothoven, who documented the crustacean’s presence here. The finding will be announced in the March 2007 issue of the Journal of Great Lakes Research. The shrimp has already been documented in parts of Europe. Exotic species documented in the Great Lakes now number more than 180, with new invaders discovered at a rate of one every eight months. Pothoven said the mysid, which prefers warm, shallow waters with rocky bottoms, is unlikely to compete with a native shrimp species that prefers cold, deep waters and is an important food source for fish. But he said it could create a “bottleneck” at the base of the food chain by eating microscopic zooplankton favoured by tiny fish.