Abstract
The Island Apple Snail, Pomacea maculata (Perry, 1810) (Caenogastropoda: Ampullariidae), is a large, aquatic gastropod native to warm-temperate and tropical South America (Conner, Pomory & Darby, 2008). The snail was introduced into Florida and Texas during the early 1990s and quickly spread throughout the southeastern USA (Byers et al., 2013). In contrast with its Florida-native congener P. paludosa, which feeds largely on periphyton and detritus, P. maculata feeds predominately on macrophytes (Sharfstein & Steinman, 2001; Horgan, Stuart & Kudavidanage, 2014). The diet of P. maculata, in conjunction with its high growth and reproductive rates, can lead to rapid changes in the structure and function of invaded ecosystems (Burks, Kyle & Trawick, 2010; Martin & Valentine, 2011; Horgan et al., 2014). Overgrazing by invasive Pomacea spp. on a variety of emergent and submerged aquatic vegetation (SAV) species has been documented in natural lakes and wetlands (Carlsson, Bronmark & Hanson, 2004; Martin, Bayha & Valentine, 2012; Horgan et al., 2014), in engineered wetlands and waterways (Teem et al., 2013; Horgan et al., 2014; Hayes et al., 2015) and in agricultural ecosystems (Cowie, 2002; Joshi & Sebastian, 2006). This study addressed impacts of herbivory by P. maculata on the highly valued SAV Vallisneria americana.
