A combination of approximately 600-800 canvasback and redhead ducks have turned up dead along the St. Clair River and Lake St. Clair shorelines, according to the Department of Natural Resources. The die-off likely has been caused by malnutrition, as toxicology tests on the ducks have ruled out other causes, DNR wildlife biologists said.

"We are receiving reports from several spots along the St. Clair River and Lake St. Clair shoreline of lethargic acting and dead ducks, and expect more reports as the weather warms up and more carcasses are recovered," said Tom Cooley, wildlife biologist at the DNR's Wildlife Disease Lab. "The Lake St. Clair area is a wintering area for large numbers of these duck species, and every year we see more and more ducks in the area, which is making for greater competition for available natural food."

Wildlife biologists along Lake St. Clair have collected samples of the dead ducks for disease and toxicology testing. The biologists have noted there are more canvasback ducks being affected than redheads. Cooley said that last winter, various waterfowl species were found dead in the same areas, and those deaths were attributed to malnutrition as well.

Lake St. Clair is a primary wintering spot for both canvasback and redhead ducks due to its large expanse of water and availability of food, such as wild celery. Some waterfowl do leave the lake and migrate either to the East Coast or to the Gulf of Mexico; however, DNR biologists have observed that there were a larger number of waterfowl staying the entire winter this year.

"Normally, we see 20,000 to 30,000 ducks spending the winter on the lake," said DNR Wildlife Biologist Ernie Kafcas, stationed at the Lake St. Clair Fish Research Station. "However, this winter, we are seeing 30,000 to 40,000 ducks staying because the waters stayed open later this winter and did not experience a hard freeze until after mid-January. Ducks that go into the winter with low fat reserves and have to compete for food in extreme late winter conditions are more prone to deaths due to malnutrition."

Residents concerned with the die-off should contact the nearest DNR office to report any ducks or other species of shore birds that they find dead in the area. Reports can be made online at www.michigandnr.com/diseasedwildlifereporting/disease_obsreport.asp.