There actually is a large snail dubbed “Chinese Mystery Snail.” They were introduced into inland lakes from home aquariums and bait buckets, and from boats with exposure to larger lakes where ships’ ballast water has been dumped. The UW-Madison Center for Limnology surveyed 45 Wisconsin lakes and found these snails in 40%. They warn that the invaders have strong negative effects on native snails. These snails are about 2-¼” long are relatively immune from rusty crayfish attacks, so the crayfish feed on the native snails.
We reported in our April edition that Mystery Snails had been identified in our Chain’s lakes and rivers. The Trout Lake Limnology Station has a research project underway to study impacts of these kinds of snails on our waters under the direction of Missouri State U. Professor John Havel. It’s already clear that these larger snails compete with native species for food and space which may result in devastation of native species.
If you want to check for the Mystery Snails, look for them along the high water mark of your shoreline, especially if it is on the downwind side of a lake. You can also see them in shallows and out into a lake up to a depth of 15 ft. For identification purposes, go to:
http://www.iisgcp.org/EXOTICSP/Oriental_Mystery_Snail.htm Professor Havel is working out of the Trout Lake Station this summer and would like to hear from you if you spotted the invaders. Email him at JohnHavel@MissouriState.edu.