Wednesday, December 5, 2007

Botulism E update - Lake Michigan

Below is an update from Common Coast Research & Conservation about bolulism E deaths along the south shore of Lake Michagen. Check back for more updates as they become available!

Dear Birders,
In response to the recent appearance of many dead birds along the Lake Michigan shoreline, for the past three weeks our research group has been surveying beaches in both the Upper and northern Lower Peninsulas. As of November 18 we have recorded just over 2000 dead birds on 93 miles of shoreline stretching between Peninsula Point in Delta County and Cathead Point in Leelanau County, an average of 21.6 dead birds per mile. As a conservative estimate of the total shoreline distance between these endpoints is roughly 350 miles, 7500 birds have potentially perished within this region alone. It is worth noting that the die-off has been reported further to the west in the Upper Peninsula (Menominee), to the south in the Lower Peninsula (Frankfort), and on islands such as Beaver and the Manitous. The top five species that we have documented are Common Loon [n=508], Long-tailed Duck [n=505], White-winged Scoter [n=207], Red-necked Grebe [n=166] and merganser sp. (primarily Red-breasted) [n=127]. Other recorded species include Red-throated Loon, Double-crested Cormorant, Ring-billed and Herring Gulls, Horned Grebe, and Bald Eagle. The most notable Common Loon among our recoveries was a banded adult from Seney NWR who had been monitored on the refuge for 14 years and during this time had produced 17 chicks - including one this season. His discovery stands as the first evidence that a portion of the very high Common Loon numbers represent birds breeding in Michigan, where the species remains a Threatened Species.
Carcasses from a wide variety of bird species collected along the lake have tested positive for botulism E at the Michigan DNR's Wildlife Disease Lab. This current outbreak on Lake Michigan follows a trend of increasing botulism-related mortality on the Great Lakes; only Lake Superior has thus far remained exempt from the problem. To learn more about botulism E consult the Michigan Sea Grant website at We would be interested in any update on the location and/or density of bird carcasses along the Great Lakes shoreline, and would greatly appreciate being contacted if a banded loon is discovered by any birder. Additionally, birders can submit unusual numbers of dead birds to the DNR's Wildlife Disease Lab a using the following web site:,1607,7-186-25805-75891--,00.html

Joe Kaplan
Common Coast Research & Conservation

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