The Shield Limpet is a common animal you can easily find around Puget Sound at low tide. Like snails, Limpets are gastropods though they look very different. Next time you visit the beach, look for tiny volcano-shapes attached to big rocks or among mussel beds. Viewed from above Shield Limpets are oval with a slightly off-center peak. Their color varies from white or gray to tan or brown. It's often good camouflage.

At a bit over 2 inches wide at most, Shield Limpets are small. They clamp tight to rock with a foot-like a suction cup. This seals in moisture when the tide uncovers them. As the tide returns, the Limpet begins to wander across the rock, scraping and eating algae. An important part of the Limpet's anatomy is key to this grazing — the radula ("rád-ū-lă"), a little strap with file-like teeth that rasps tiny plants and seaweeds. Eating its way across the rock, the Limpet leaves a curving trail and goes back to start before the tide recedes again. Look for these trails and see what this creature's been up to.

By returning to the same place again and again and rasping a bit each time, the Shield Limpet wears a depression. That slight indentation in the stone helps the Limpet get an even better seal and resist attacks by the many limpet-eaters: crabs, fish, sea stars, predatory snails, birds called "oystercatchers," and more. Youíll notice faded oval spots on rocks where Limpets used to be.

These creatures are important food for many other animals, so people shouldn't pry them off the rocks and injure them. Please just watch the Limpets and wonder at their unusual lives.