An Assessment of Submersion as a Mechanical Control Technique of Pomacea maculata eggs in Southern Florida, USA

Abstract

Pomacea insularum is a freshwater snail native to various regions of South America. In the 1990’s invasive populations of P. insularum began to establish in Texas, Florida, and Georgia. These snails have a high fecundity rate and feed on macrophytes. Water bodies in southern Florida undergo frequent fluctuations in water levels; most are controlled by pumps, culverts, gates and levees. A proposed control method for these snails is the inundation of the egg clutches. This study compared the hatching success of unsubmerged egg clutches with the hatching success of partially submerged egg clutches, the growth rates of snails hatched in the treatments, and determined if snails hatched in submerged conditions are viable to a shell length that exceeds 25 mm, a size typically capable of reproduction. Hatchling success was not significantly different amongst treatments; likewise, growth rates were similar despite inundation. Pomacea insularum egg clutches submerged at various times during their incubation can become detached from the vegetation and sink or float. Floating egg clutches can be transported through water control structures and canals, thus facilitating the spread to non-impacted areas. Manual methods for removal of egg clutches and adults may prove more effective in control efforts.