Apple Snails

Pomacea maculata

Lake Seminole is now home to two primary species of Apple Snail. The native Florida Apple Snail (Pomacea paludosa) and the non-native Island Apple Snail (Pomacea maculata). The Island Apple Snail was introduced to Lake Seminole in 2003. Because of its need for calcium to support rapid shell growth, the Island Apple Snail is believed to be a voracious eater of hydrilla, which is the highest source of calcium among aquatic plants. It was believed that the Island Apple Snail could help manage hydrilla which is also a non-native invasive. Non-native Pomacea maculata is larger than native Pomacea paludosa, generates more eggs, grows bigger faster and lives longer. Early studies have shown P. maculata primarily in the eastern parts of the Flint River where it was first introduced. Whereas P. paludosa was dominant in the Chattahoochee and western Flint River and Spring Creek. P. maculata has gradually moved into these areas inhabited by P. paludosa. The eggs of the Florida Apple Snail are larger, chalky white/peach and are the size of a pea. The eggs of the Island Apple Snails are the size of a tomato seed and are bright pink.

Although apple snails will deposit their eggs on aquatic vegetation, because of their size and weight they prefer fixed structures. They can lay up to 2000 eggs that will hatch within 7-14 days. The hatchlings are about 2mm in size and make perfect food for Lake Seminole’s shellcrackers. At 1.5cm in size their diet shifts from decayed organic material to aquatic plants. The Island Apple Snails are hermaphroditic and can reproduce 2-3 months after hatching. An adult apple snail can lay a cluster of eggs every 14 days. You can do the math to understand the explosive population growth rate and the potential disruption to the ecological processes in a balanced ecosystem. (Perhaps this is why our shellcrackers seem to be getting larger?)

The eggs of an apple snail are toxic and indigestible to protect them from predators. Fire ants are the only known predator. The eggs in some species contain powerful neurotoxins. DO NOT HANDLE THE EGGS WITH BARE HANDS! Recent research suggests Pomacea maculata can transfer neurotoxins to its avian predators. The snail kite, one of the avian predators of the apple snail, has seemingly experienced decreased foraging success and juvenile survival following the invasion of Pomacea maculata.

The Island Apple Snail is the largest non-marine snail in the Southeastern United States. It is now the most common apple snail found in Lake Seminole. The apple snail is raised for food in some areas. It is known to carry rat lung disease and must be thoroughly cooked for human consumption to prevent sickness. Natural predators are the Limpkin, Snail Kite, Racoons, Otters, turtles and alligators.

The Island Apple Snail is just one of many invasive species impacting Lake Seminole. If you take a close look at your boat dock or sea wall, you may notice the pink eggs that belong to this species. Whether they are friend are foe is still to be determined. For more information see the links below.

The Apple Snail (Ampullariidae) Website

Island Apple Snail (UGA)

Of Limpkins and Apple Snails: Invasive Species, Novel Ecosystems, and an Uncertain Future