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This article is to make you aware of a new threat to your expensive canoes and kayaks. Be sure to read all the way through and click on all the photos so that you understand the situation. Reports are starting to come in from paddlers in southern states of damage to their boats from snails. Yes, that's right, snails. They seem cute and harmless enough. But some of them can be quite ferocious, on the snail scale of things. There are certain types of snails called molluscivores, which prey upon mollusks (mussels, clams, etc.), by using sharp little teeth called radula, to drill a hole through the shell of their victim. They then inject a venom to kill the organism inside, along with some digestive enzymes to turn them into clam chowder. The predator snail then sucks out the soup through the hole he drilled, to enjoy an appetizing and fulfilling meal. You may even have noticed that some shells contain holes and wondered how that happened. Now you know. Snail mouth Snail teeth in action Microscope image of radula Mollusk victims This process has been going on for eons and is part of nature. So, what's the problem, you ask? Well, with the explosion of popularity for canoes and kayaks, with more paddlers than ever before on the water, it seems that some of these snails have taken to attacking the hulls of boats. Perhaps they mistake a canoe for a giant clam, and see it as a prime target of opportunity. This is happening most often with white or tan boats, which mimic the natural colors of shellfish. They attack the thin plastic, fiberglass or kevlar hulls with vigor, rasping their way through with their sharp little teeth. The snails are then mightily disappointed after all that work to find that there is no meat inside that giant clam. However, the damage is done, and the boat owner now has a small hole in his hull. If the kayaker is really unlucky, he might have multiple snails attack simultaneously, leaving multiple holes in the boat. And gosh forbid you should leave the boat floating in the water on an overnight camping trip, only to get ready to pack in the morning and find your boat looking like Swiss cheese. If you have an aluminum boat, you're safe - they can't chew their way through that! Biologists are stumped as to why this has started happening. But they speculate that it may have to do with declining numbers of shellfish prey, and increasing numbers of kayaks. To a hungry snail, a kayak can look just like a large shellfish. So this may just be an adaptation in response to scarce food resources. There is, as yet, no known solution to this problem. These snails inhabit both fresh and salt waters, and could be in any waterway. The best you can do is preventative action - don't leave your boat in the water stationary and unattended. And when you pull it out of the water, check it for attached snails and knock them off, before they have time to finish their work. For an expedition trip, make sure you have some temporary repair material to cover any holes, or some high density foam rubber to stuff into the holes to plug them. Here are several photos of examples of boat hulls which have been attacked by snails. Check them out! Hole in kevlar Swiss cheese! (Click to enlarge) Good luck!