Meeting Abstract

P3.39  Sunday, Jan. 6  Effects of pesticide and salinity on sperm activity in the green tree frog (Hyla cinerea) WILDER, A.E.*; WELCH, A.M.; College of Charleston, SC; College of Charleston, SC aewilder@g.cofc.edu

Increased salinity in freshwater habitats can result from anthropogenic factors such as climate change and sea level rise, use of road salts, over-irrigation and groundwater depletion. This emerging threat can affect freshwater species in both coastal and inland environments. Pesticides have also been found in freshwater environments around the globe, and can be harmful to many different aquatic organisms. Amphibians are highly sensitive to changes in their surroundings, making them good indicators of environmental quality, especially in freshwater habitats. This study examined the effects of increased salinity and a common insecticide, carbaryl, on sperm activity in the green tree frog (Hyla cinerea). Because amphibians have external fertilization, sperm must be able to move effectively in the water source in which breeding occurs to ensure successful fertilization. To test effects of salinity on sperm activity, we subjected H. cinerea sperm to levels of salinity ranging from freshwater to moderately brackish and analyzed activity using computer assisted sperm analysis (CASA). Effects of carbaryl on sperm activity were measured in a similar fashion, using concentrations ranging from zero to a dose that is beyond the expected field concentration. Mean sperm motility and velocity were both found to decrease as salinity increased. The effect of carbaryl on sperm activity appears to be less deleterious than that of salinity. These findings suggest that increased salinity in freshwater habitats could negatively affect reproductive success of H. cinerea. This disruption of the life cycle could lead to population declines, unless individuals are able to find more suitable breeding sites.