Friday, October 28, 2011

Botulism confirmed in Ontario bird die-off (Reasonable explanation for event killing thousands of birds?)

Preliminary testing confirms that the thousands of dead birds that washed ashore along a stretch of Ontario’s Georgian Bay appear to have died of botulism.

The first bird to be tested, at the University of Guelph, came back positive for Type E botulism, a spokesperson for the provincial Natural Resources Ministry said Thursday.

The birds would have eaten fish laced with botulism toxin, the ministry said.

Thousands of dead loons, ducks and gulls washed ashore along a three-kilometre stretch around Wasaga Beach, on the southeast part of Georgian Bay.

Ministry spokeswoman Jolanta Kowalski said other samples of the thousands of dead birds have been sent for testing, with more results expected next week.

Such die-offs are common in the fall and residents shouldn't be concerned if dead birds wash ashore, she said. "It could continue for a few more weeks depending on water temperature, waves," Kowalski added.

Type E botulism toxin is produced by a bacterium that lives in lake bottom sediment, and under certain conditions it begins producing the toxin, which then enters the aquatic food chain, according to the ministry. Birds who eat affected fish can die.

Botulism toxins are easily destroyed by heat, meaning fish and birds that people catch pose no risk provided they're properly cooked. However, residents in the area are being warned to keep a tight rein on their pets and prevent them from getting near the dead birds and fish on the beaches. more