Migratory Birds and Botulism
More than 100 dead loons and other migratory birds have washed up on Great Lakes shores this month. The number one suspect for the birds’ deaths is botulism poisoning linked to the spread of invasive species.
Preliminary evidence closely matches die-offs related to Type E botulism that have occurred every year on Lake Erie since 2000 and Lake Ontario since 2002, during fall migration. Those incidents are tied to two invasive species consumed by birds during migration stopovers: the quagga mussel and the Round Goby. Loons especially feed on the Round Goby. Other birds impacted include the Red-breasted Merganser, Ring-billed Gull, Herring Gull, Great Black-backed Gull, Horned Grebe, Long-tailed Duck, Greater Scaup, Double-crested Cormorant and the White-winged Scoter.
Type E botulism is a specific strain of botulism most commonly affecting fish-eating birds. It causes paralysis in the affected birds and is often fatal. The disease results from the ingestion of a toxin produced by the botulism bacterium and can be harmful to humans who eat birds or fish that have been poisoned by this toxin. Hunters and anglers are advised not to harvest waterfowl or fish that are appear to be sick.
November 15, 2007 8:57 AM | Category: Invasive Species