This year’s die-off of eider ducks on Cape Cod appears to be higher than in past years.

WELLFLEET, Mass. (AP) – Hundreds of sick and dying sea ducks have been washing up on Cape Cod over the past week, raising worries from wildlife experts about the unusually high die-off of the birds.

Bob Prescott, director of the Massachusetts Audubon Society Wellfleet Bay Wildlife Sanctuary, said the die-off of common eiders happens annually, but said this year’s death toll appears higher than usual.

He said biologists don’t yet know the cause of the deaths each year.

Eiders are not an endangered species, but Prescott said they are not doing well in Maine, where biologists have not seen large numbers of young in springtime.

“It’s not good news for them to be having this mortality (on the Cape),” Prescott told the Cape Cod Times.

Cape Cod National Seashore wildlife biologist Bob Cook said a few dozen dead eiders typically wash up each spring. This year, field reports from his researchers indicate this year’s numbers appear higher than any previous year.

Two dead eiders were sent last Monday to the National Wildlife Health Laboratory in Madison, Wis., for tests. Results are not expected for a couple of months, but tests from previous years have not indicated any conclusive cause of death.

Eiders are the Northeast’s largest duck, measuring about two feet and weighing about 6 pounds. Male eiders have bright white plumage on their upper bodies and dark plumage below. Eider down, the bird’s breast feathers, are coveted for their softness.

Eiders are sea ducks that make their nests along coastal areas. They’re commonly found in the northern coastal areas of North America, Europe and Siberia.

AP-ES-05-16-04 0955EDT

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