The ecology of a new invasion by Bellamya japonica in the Savannah basin

The first known infestation of Bellamya japonica in the Savannah River Basin was discovered in 2006. Investigations of this population led to questions regarding their distribution and behavior. We have completed experiments on behavior and concluded that there exists a significant negative phototactic but no detectable geotactic response. In addition, a study of their dispersal using mark-recapture methods concluded that, while this technique was useful to follow the life history of individual snails, they did not meet the method assumptions and therefore this method could not produce a reliable population estimate. Studies of fecundity have shown a seasonal trend with an unsurprising correlation to water temperatures and time-of-year. Fecundity rates are still being assessed. Age is difficult to determine and the life history studies using marked snails will assist with this as well. Metabolism is unknown for this species but methods are currently being developed. Anecdotal observations suggested a possible circadian rhythm with regard to fecundity. A systematic study of this phenomenon is also in progress. If successful our studies may help with management of this infestation in the future