Thursday, November 15, 2007

Migratory Bird Deaths Linked to new Invasive Species

More than 100 dead loons and other migratory birds have washed up on New York's Great Lakes shores in the past week, prompting the New York State Department of Environmental Conservation (DEC) to suspect another botulism-poisoning episode linked to the spread of invasive species.

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 a fish called the Round Goby. Loons especially feed on the Round Goby. As the Round Gobies have proliferated in in Eastern Lake Ontario, cases of botulism poisoning have increased. This is now an annual event.

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. The single species with the greatest mortality has differed each year.

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