Every year in late summer and early fall, dead bodies of water birds are found along the shores of the Great Lakes and, to a lesser extent, on inland lakes. Common loons, ducks, geese and sometimes gulls are affected. Some years are worse than others and during the summer of 2002, a record high of 14,000 birds washed to the shore of Lake Erie and, before that, more than 10,000 dead loons on the Great Lakes in one year.
These deaths are attributed to avian botulism, also called western duck sickness, which acts like food poisoning and can reoccur. The bird ingests a toxin produced by the bacteria Clostridium botulinum and become paralyzed and unable to hold their heads up (called limpneck). Their heads fall into the water and the bird drowns.
Birds that are able to struggle ashore are unable to move and die from the cold, respiratory failure, or a predator. Birds can recover if kept warm and safe in a sheltered location. This bacterium is widespread in soil, living for a long time and requires warm temperatures, a protein source, and an anaerobic (no oxygen) environment in order to become active and produce the toxin.
These conditions are more prevalent in our lakes now with warmer temperatures and higher nutrient loading causing more plant growth resulting in more decomposing vegetation which causes lower oxygen levels. A wide variety of birds and some mammal species are susceptible to the disease and databases have been compiled in recent years to monitor these deaths and th.