Movement of Maculata Applesnails in Southern Louisiana Swamps

Science Center Objects

Maculata applesnails (Pomacea maculata) are exotic freshwater snails that have been widely introduced along the Gulf of Mexico coast. They can significantly impact freshwater macrophytes and reduce water quality.

Maculata applesnail (Pomacea maculata)
Maculata applesnail (Pomacea maculata)

The Science Issue and Relevance: Maculata applesnails (Pomacea maculata) are exotic freshwater snails that have been widely introduced along the Gulf of Mexico coast. They can significantly impact freshwater macrophytes and reduce water quality. Their presence is easy to detect by the presence of their distinctive egg masses. Anecdotal observations indicate that P. maculata applesnails may face an array of predation pressures. Little is known about their movement, impacts of predators, or abundance. Concurrent research regarding abundance and predation has been designed to address questions about the fate of snails not recaptured (in the case of abundance) or lost from their tethers (in the case of predation). Furthermore, it is not known how far snails move over a given period of time or if they have home ranges. The ability to track mobility of individual snails will allow us to better understand (1) the fate of snails over time; (2) movement behavior and the impact on patterns of invasion or susceptibility to control measures.

Methodologies for Addressing the Issue: Radio telemetry devices are being attached to snails larger than 30grams at different monitoring sites along the Levee and within Bayou aux Carpes at Jean Lafitte National Park. Tracked snails are used to (1) determine how far living snails move over time and if they exhibit any home range behavior, and (2) more accurately determine the fate of snails not recaptured in the abundance study or that disappeared from their tethers in the predation study. The release location of the snails is marked and recorded, and on subsequent site visits radio tagged snails are relocated, fate established (dead or alive), weighed and measured if alive, sex determined if possible, and the distance and direction from the last known location recorded. Live snails are released where found and a marker put in place so the release site can be relocated.

Future Steps: This study will be conducted for 3 years, replacing radio telemetry devices as needed. Results of this study will be used by companion research on abundance and predation of applesnails.

Related Projects:

  • Identifying Applesnail Predators and Predation Rates
  • Movement Patterns of Applesnails in Louisiana Swamp Forests
  • Will Maculata Applesnail Eat Native Amphibian Eggs?
  • Modeling the Population Dynamics of Maculata Applesnails
  • Estimating Applesnail Populations at Jean Lafitte National Park