2-03-03
PENNSYLVANIA SEA GRANT PROVIDES
LEADERSHIP FOR AVIAN BOTULISM TASK FORCE
Over the past three years the Lake Erie watershed has experienced an increasing die-off of thousands of gulls, loons, and other fish-eating birds as a result of type-E avian botulism. Pennsylvania Sea Grant, in partnership with New York and Ohio Sea Grant programs, has taken the lead in developing a task force to address this problem and obtain funding for related research.
"We serve as a clearinghouse for reports on avian botulism in Lake Erie and Lake Ontario," said Eric Obert, associate director of Pennsylvania Sea Grant, an outreach center of Penn State Erie, The Behrend College. "More than 5,000 birds were reported dead by the first two weeks in November 2002, and we continued to receive reports of dead birds through the end of the year. We saw large die-offs during this year's fall migration, mostly loons, mergansers, and long-tailed ducks."
Obert, who also teaches in Behrend's School of Science and serves as chair of the Great Lakes Sea Grant Network for Extension Leaders, maintains and updates a listserve for the Avian Botulism Task Force based on reports sent to him by the U.S. Geological Survey National Wildlife Health Center, the Pennsylvania Department of Conservation and Natural Resources, Pennsylvania Game Commission, Pennsylvania Fish and Boat Commission, Erie County Health Department, New York State Department of Environmental Conservation, Canadian Wildlife Service of Environment Canada, and representatives of New York and Ohio Sea Grant, regional conservation organizations, area colleges and universities, and wildlife biologists throughout the Great Lakes.
"We're in the process of preparing our third workshop to address problems associated with avian botulism in Lakes Erie and Ontario," said Obert, "and we expect to offer it in late March or early April this year. More than seventy researchers from the United States and Canada attended the first workshop in Erie in 2001, and more than 120 researchers and agency representatives attended the second workshop in Buffalo in 2002."
Research on the history and spread of type E botulism indicates that the current outbreak may be related to lower Great Lakes water levels, which raise the water temperature. More sunlight penetrates the water, resulting in more algae which, as it dies, creates the anaerobic environment needed for type E botulism to survive. Scientists also believe that zebra and quagga mussels, which provide food for fish, exude a form of pseudofeces that may play a role in creating small anaerobic niches necessary for the formation of botulism.
"As fish eat the infected mussels and die, the fish are eaten by shore birds, who are then infected," said Obert. "In just one year this outbreak of type E botulism spread from west to east, from one end of Lake Erie to the other. New reports were received this year of botulism outbreaks on Lake Ontario."
Avian botulism has been recognized as a major cause of death in migratory birds since the early 1900s. Botulism is classified into seven types, A through G, with type E restricted mainly to fish-eating birds in and around the Great Lakes. The neurotoxins produced by the botulism bacteria bind to receptors on nerve endings of vertebrates, impacting muscular function and, in the case of birds, resulting in drowning. In the past two years, many fish and mudpuppies have also fallen victim to this bacteria.
Pennsylvania Sea Grant distributes health advisory posters and fact sheets to those who use the Great Lakes shores, including fishermen, hunters, boaters, and swimmers.
"While the chance of getting botulism is slim, people should be aware of the dangers associated with harvesting fish and wildlife from the Great Lakes," said Obert. "Never harvest a fish floating in the water that you did not catch. Since botulism quickly affects the nervous system of vertebrate animals, it is unlikely that a fish that gives you a fight at the end of your line will have botulism."
Procedures for safe handling of dead birds and fish can be found on the Pennsylvania Sea Grant Web site.
"Anglers and hunters need to be updated on safety procedures to use in handling, cooking, and smoking fish and waterfowl," said Obert. "We also encourage individuals to notify us or one of the area environmental agencies of any fish or bird mortalities so we can record the location, type of bird or fish, and the number of carcasses."
Other partners in the study of the current outbreak of avian botulism include the New York State Department of Environmental Conservation, Environment Canada, Canadian Wildlife Service, Canadian Cooperative Wildlife Health Center at the University of Guelph, Mercyhurst College, the U.S. Geological Survey 's National Wildlife Health Center, Cornell University's Aquatic animal Health Program, and the Great Lakes Research Consortium.
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Contact:
Loretta Brandon
(814) 898-6063 (O)
(814) 864-9922 (H)
e-mail: lzb6@psu.edu