Watershed Council Advises: Do Not Handle Dead Fish or Birds, or Allow Contact With Pets

Loons, mergansers, grebes, and piping plovers are among thousands of birds found dead on the Lake Michigan shoreline this year. Type E botulism has been confirmed by the Michigan Department of Natural Resources (MDNR) in specimens collected from Sleeping Bear Dunes National Lakeshore in the south to Wilderness State Park in the north. Tip of the Mitt Watershed Council in Petoskey has received numerous phone calls reporting dead birds from Grand Traverse Bay to Sturgeon Bay and is working with Michigan Sea Grant and the MDNR to report affected areas.

Dead birds have been reported washed ashore along Lake Michigan in Mackinac County, as The St. Ignace News reported November 8. Fish are consuming Type E botulism, and birds are consuming the fish.

Type E botulism is brought on by the consumption of a natural toxin and is found in low-oxygen environments, such as lake sediments, where it is taken in by fish, according to the MDNR. Affected fish experience a loss of equilibrium and exhibit unusual behavior, such as swimming erratically or floating near the surface. These fish become easy targets, and birds feeding on dead or dying fish are in turn affected. Great Lakes fish that have been affected by botulism include freshwater drum, smallmouth bass, rock bass, stonecats, round gobies, channel catfish, alewives, and sturgeon.

Avian botulism was first documented in the Great Lakes in the 1960s, but there were no confirmed cases in Lake Michigan between 1983 and 2006. Last year, the bird kill was limited to a small geographic area in Benzie and Leelanau counties, Ken Hyde from the National Park Service reported.

"Sleeping Bear Dunes lost approximately 2,900 birds in 2006," he said.

This year, Mr. Hyde reports lower numbers with more than 1,000 dead birds documented in the same area, however, the geographic range of the epidemic has grown considerably, with dead birds being reported up and down the shore, from Sleeping Bear Dunes to the Straits of Mackinac.

Although uncertain, recent outbreaks may be linked to lake ecosystem disruptions caused by low lake levels and aquatic invasive species, such as the zebra mussel and round goby. The bird kills also occur in waves, depending upon environmental conditions. Recent die offs on the Lake Michigan shoreline are believed to be the result of autumnal changes in the lake ecosystem, combined with the fact that a great number of birds are migrating through the region.

The current outbreak poses little danger to people, the Tip of the Mitt Watershed Council reports, since most bird species affected are not typically eaten by people and thorough cooking destroys the toxin. Kevin Cronk, monitoring and research coordinator at the council, advises that "everyone take precautions if handling dead birds, by using disposable gloves and washing thoroughly afterward. Anglers and hunters should avoid fish and waterfowl that are easy pickings due to strange behavior, such as lethargy and erratic swimming. All fish and game should be cooked thoroughly so as not to take any chances."

What You Can Do:

Remove dead birds and fish immediately, to prevent the spread of botulism, as the bacteria in the carcasses can serve as the source of outbreaks for months.The following guidelines are advised for handling carcasses and monitoring the beach area:

• Do not handle dead fish or birds with bare hands.

• Properly dispose of carcasses by double bagging and placing them in the trash.

• Beware of fish that are floating. If they are not fighting, they are likely not healthy, and should not be consumed.

• Do not eat undercooked or improperly prepared fish or waterfowl.

• Hunters should never harvest birds that appear to be sick or are dying.

• Do not let pets eat dead fish or birds.

• Look for carcasses at two peak times: in mid-late summer and in the fall, and follow proper disposal methods.

Botulism has been identified as a problem for fish and birds in Lakes Ontario, Erie, and Michigan.