Thousands of loons dying in Great Lakes area; Birds succumb to bacteria from infected fish
December 30, 07 by TheFleetIf you're new here, you may want to subscribe to our RSS feed. Thanks for visiting!
Note: The round goby is an invasive species that was brought to the Great Lakes by trans-oceanic ship ballast. Information here.
By TOM MEERSMAN | Source: Milwaukee Journal-Sentinel
Minneapolis - The loon, an icon of the North Woods, is dying by the thousands across a growing swath of the Great Lakes, victims of a bacterial disease that works its way up from the lake floor.
First noticed in the eastern portion of the Great Lakes chain eight years ago, deaths have spread west to Lake Michigan. So far, loons have not suffered die-offs in Lake Superior, but officials are concerned about the potential in Duluth-Superior harbor.
Scientists think the birds are killed by Type E botulism that works its way up the food chain from the bottom of the lake. There, naturally occurring botulism spores germinate and grow into toxin-producing bacterial cells. Those bacteria move into quagga mussels as they filter the water.
Then a small fish called a round goby picks up the bacteria by eating the mussels.
When loons, long-tailed ducks, gulls, grebes and other birds eat the infected fish, the toxin enters their systems, paralyzing the birds. Within hours, they can no longer fly or hold their necks up, and they drown.
