Scientists are trying to figure out why dozens of dead birds have been washing up on the Georgian Bay shoreline again in recent days. Local residents are concerned over what it might say about the health of the lake.

The waterfront there is a popular place to walk but residents are finding numerous dead birds on the beach. It’s something that has happened before.

Faye Ego takes daily walks along the Georgian Bay shoreline at Allenwood Beach. Ego enjoys watching the wildlife, but sometimes she sees more dead birds than live ones. She’s concerned about the bay’s health.

“To us and to our neighbours and friends it’s about what's going on,” she says. “Like why are they dying? There has to be a reason for wash ups. And some years you see hundreds and hundreds. But every year you do see some. You look at them they are young you wonder why did it die?”

Over the long weekend dozens of dead ducks and loons washed in along Wasaga Beach. Wardens with the provincial park collected them. The Ministry of Natural Resources has sent some birds away for testing, but botulism poisoning is suspected because of another massive die off of ducks here in the fall two years ago. It was confirmed then that botulism was the culprit.

Botulism grows in low-oxygen environments at the bottom of the lake where zebra mussels grow in large numbers.

Dr. George Peck is an ornithologist and assistant researcher with the Royal Ontario Museum.

He says the birds being affected – long tail ducks, scoters, loons, and grebes – are all diving birds that are eating the contaminated zebra mussels or small fish during their migration.

“All I can think of is that this is going to lead to the decline of some of these birds, certainly as they migrate through the lakes, the long tail ducks and scoters do not breed in this area but they are migrating through this area,” Peck says.

Shoreline residents wanting to dispose of dead birds can bury them or double bag them and put them in with their regular garbage pick-up for landfill.

Fay Ego says it’s always disturbing to see wildlife dying and is concerned that this die off isn't over yet.

“The next big wind, storm it will be telling what happens then,” she says.

Residents around Georgian Bay have been asked to contact the Ministry of Natural Resources if they see signs of large wildlife die-off in their area.