Living Sanibel: Common land snail thrives under Florida sun
Well adapted to tropical regions, the land snail is a common sighting on both Sanibel and Captiva. Two specific adaptations allow this small mollusk to thrive under the hot Florida sun in times of both drought and deluge. The first is that unlike many land snails, the land snail has a shell “door,” or operculum, which it closes during the dry season to preserve its internal moisture. The second amazing adaptation is the envy of every scuba diver: it has both gills and lungs to take in the oxygen every animal needs to survive.
The right side of this snail’s body contains a system comparable to the gills of a fish, allowing it to survive and breathe underwater, while the left side has a primitive but effective lung allowing the snail to breathe air. When the food supply runs low in a nearby pond, the land snail crawls out of the water and starts to forage on land. It eats algae, plants, brine shrimp, carrion and even small insects. The land snail is a freshwater gastropod and a true omnivore.
The name land snail description applies to a wide array of species. Some aquarium varieties can be six inches in diameter. This snail is heavily preyed upon by birds such as the red-winged blackbird, as well as lizards, juvenile alligators, bass, rodents and larger mammals such as raccoons and otters.
This is an excerpt from Living Sanibel – A Nature Guide to Sanibel & Captiva Islands by Charles Sobczak. The book is available at all the Island bookstores, Baileys, Jerry’s and your favorite online sites.