more on the recent great lakes bird deaths

The likely cause:

How birds become exposed to botulism, Cooley explained, begins with a bacteria called clostridium botulism. This bacteria thrives in water with low oxygen levels producing a toxin that can get into sediments. Invasive species like quagga and zebra mussels filter the sediments and pick up the bacteria which they pass onto other aquatic life like round gobies which eat the mussels. From there, birds eat the fish.

http://www.petoskeynews.com/articles/2007/11/24/news/news04.txt

Another ballast water gift. Will Congress ever slam the door on the sickness introduced by oceangoing vessels whose owners can (and must) shoulder the cost of stopping invasive species?