<table border=0 width=550 cellpadding=6><tr bgcolor="#CCCCCC"><td> <font face="arial,helvetica" size=2> This article from <a href="http://www.startribune.com";>StarTribune.com</a> has been sent to you by Kathy Confer.<br> <b>*Please note, the sender's identity has not been verified.</b><br><br> The full article, with any associated images and links can be viewed <a href="http://www.startribune.com/531/story/764349.html"; target="_new">here</a>.<br>Kathy Confer wrote these comments: ...an interesting and sobering article from today's StarTribune Web site...Kathy Confer, U of MN<br><br></td></tr><tr><td><font face="arial,helvetica" size=2><b>Botulism is killing migratory birds in Lake Michigan</b><br><a href='mailto:meers...@startribune.com'>Tom Meersman</a>, Star Tribune<br/><br/>Hundreds of loons, grebes, mergansers, cormorants and other migrating birds have been killed in Lake Michigan recently, most likely from bacteria linked to non-native fish and mussels.<br/><br/>Biologists at Sleeping Bear Dunes National Lakeshore estimated this week that 2,600 dead birds have washed up on beaches during the past two months. It is the first large-scale bird die-off in Lake Michigan in decades.<br/><br/>"I've worked here for almost 30 years and I've never seen anything like it," said Steve Yancho, chief of natural resources at the park's office! in Empire, Mich. He said the cause of the deaths seems to be Type E botulism, which occurs naturally in the sediment of the lake, but rarely enters the food chain.<br/><br/>Many wildlife biologists around the Great Lakes have noted similar mass bird deaths since 1999 in Lakes Erie, Ontario and Huron. Lake Superior seems to be the only Great Lake that has not been affected so far, said Doug Jensen, aquatic invasive species coordinator for the Minnesota Sea Grant at the University of Minnesota Duluth.<br/><br/>He said he doesn't know whether similar problems will occur in Lake Superior, because scientists are still trying to understand how water temperature and other factors may play a role in transforming the botulism bacterium into a potent neurotoxin.<br/><br/>What's clear from the evidence, said Jensen, is that the die-offs involve the interaction of two invasive species -- quagga mussels and a type of fish called round gobies -- which came originally from the Black and ! Caspian seas. They were carried into the Great Lakes in the ba! llast wa ter of oceangoing ships and have been spreading since their arrival in the late 1980s.<br/><br/>Biologists believe that the birds die as the neurotoxin makes its way through the aquatic food chain.<br/><br/>First, invasive quagga mussels move into a lake-bottom area, filter the sediment and accumulate the botulism's bacteria, which produce the toxin. Then, the round gobies eat the mussels and become contaminated. Finally, migrating birds spot the dead or dying gobies, eat them and in turn get poisoned.<br/><br/>The toxin attacks the birds' nervous system and paralyzes their muscles, causing large numbers to drown when they can no longer flap their wings or hold up their necks.<br/><br/>Large bird die-offs have occurred in late summer when gulls eat poisoned fish, but especially in the late fall when migrating birds are searching for food.<br/><br/>New York biologists picked up more than 17,000 dead birds along the southern shore of Lake Erie in 2002. The toxin has also kille! d tens of thousands of other fish that consume gobies, and the gulls that feed on them.<br/><br/>Yancho said the botulism outbreak at Sleeping Bear Dunes occurred just after the piping plover, an endangered bird species, left the area. <br/><br/>"Had they been here when this was going full speed, it could have been disastrous," he said, adding that there are only 50 pairs of piping plovers left in the Great Lakes.<br/><br/>Helen Domske, senior extension specialist at the New York Sea Grant, is especially concerned about loons.<br/><br/>"They're wonderful birds that are such a critical part of the ecosystem," she said. "You start to wonder what kind of impact so many deaths is having on the entire [loon] population."<br/><br/><p class="contact">Tom Meersman 612 673-7388 <a href='mailto:meers...@startribune.com'>meers...@startribune.com</a></td></tr></table>
