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In mid-August, ducks suspected of dying from avian botulism were collected from the pond at Loring Park and at Lake Nokomis, both in Minneapolis.

"It's almost certainly botulism but without lab testing we do not know, said Tami Vogel, communications director at the Wildlife Rehabilitation Center of Minnesota in Roseville.

"We see botulism cases flare in years of hot, drought conditions when shallow ponds/lakes become too low and an anaerobic condition occurs," she told us.

Researchers were to examine the birds to confirm cause of death.