Skip to main content

What Do You Get When You Mix an Apple With A Snail?

Apple snails can grow to the size of an apple, hence their name. They can be found in slow-moving fresh water in the tropical and subtropical areas of South America, Central America, the West Indies, Africa, and the southern United States. What’s so special about the apple snail? Allow me to explain…

The apple snail genus, Pomacea consists of at least five different species of snails: Pomacea paludosa (Florida Apple Snail), P. insularum (Island Apple Snail), P. canaliculata (Channeled Apple Snail), P. diffusa (Spike-topped Apple Snail), and P. haustrum (Titan Apple Snail). Of the five, the Florida apple snail is the only species native to Florida! It is also native to Cuba and Hispaniola. Florida apple snails can be found in wetlands throughout the state of Florida and are recorded to be the largest fresh water snail in North America, but the important thing to note is they are the main food source for the endangered Florida snail kite.

The four remaining snail species are of concern to the environment and are regarded as non-native, invasive species. Not all of these species have been recorded as damaging to the Florida ecosystem, but they do pose threats. Of the four, the Island Apple Snail is most likely to be encountered in Pinellas County. Importing or transporting this species across state lines is in violation of U.S. federal law. Serious impacts made by the Island Apple Snail have not yet been recorded, but they are a potential threat to Florida’s environment because they feed on rooted aquatic vegetation, unlike the native Florida Apple Snail that feeds on periphyton (a variety of algae that lives on the surfaces of aquatic plants). So how can you tell the Florida Apple Snail from the Island Apple Snail?

  Size Whorls # of Eggs per clutch Color of eggs Size of Eggs
Florida Apple Snail 40-70mm (1.57 to 2.76 inches) no grooves between the body whorls up to 80 eggs start salmon colored and turn pearly white about a pea size
Island Apple Snail up to a size of 120mm (4.72 inches) grooves between body whorls are deeply grooved 600-1200 start bright pink and turn white much smaller than a pea
Pomacea_paludosa_shell

Photo of shell of the native, Florida Apple Snail (Pomacea paludosa). Scale Bar: 5 cm.

Pomacea_insularum_shell

Photo of shell of the Island Apple Snail (Pomacea insularum). Scale Bar: 5 cm.

256px-Pomacea_paludosa_and_Pomacea_insularum_eggs

Photo of eggs of the native, Florida Apple Snail (Pomacea paludosa) [top] and the Island Apple Snail (Pomacea isularum) [bottom]. Scale Bar: 5 cm.

What can we do to help protect the native apple snail and the endangered snail kite that depends on it?

Managing invasive apple snails is fairly simple. The most effective methods are done by hand or by mechanical removal of the snails and their egg clutches. The natural predators of the apple snail, such as: limpkins, Everglades (snail) kites, raccoons, turtles and alligators, also serve as excellent natural control methods. Chemical tactics have been used, but with little to no success.1 In removing the egg clutches you can collect the eggs and crush them. Another effective method of disposing of the snails is to freeze them for a week and then bury the snails. Only pink egg clutches should be removed because large, white egg clutches belong to the Florida apple snail, which does not pose a threat and serves as a great food source for the Everglades kite.

For more information on the different species of apple snails, management, identification, and/or more please visit http://entnemdept.ufl.edu/creatures/misc/gastro/apple_snails.htm or http://fl.biology.usgs.gov/sofla/apple_snail.pdf.

Reference:

1 http://myfwc.com/media/673720/FWC_applesnails_FLMS_handout.pdf

This article was written by my intern, Jasmine Fisher 🙂 Thank you!