MOLLUSK DISTRIBUTION WITHIN THE SALINE LAKES ON SAN SALVADOR ISLAND BAHAMAS-ESTABLISHING A BASELINE FOR DETERMINING BIOLOGICAL RESPONSE TO CLIMATE AND ANTHROPOGENIC CHANGE

San Salvador Island, Bahamas has many diverse lakes of various sizes, salinities and other environmental parameters. These lakes have faunas that are dominated by shelly invertebrates such as mollusks and ostracodes. While more is known about the ostracode community and its distribution, fairly little is understood about the mollusk community—particularly whether or not their distribution is controlled by the same variables (i.e. salinity) as ostracodes. This study examined the occurrence and abundance of the mollusks on San Salvador as well as the environmental factors that might be controlling their distribution.

During June 2009, sediment and water samples from 27 lakes on San Salvador Island, and analyzed for species content, abundance, and environmental variables, such as lake area, water depth, dissolved oxygen, conductivity, total dissolved solids and temperature. Statistical analyses completed on the samples indicate that variables such as lake area, latitude, longitude, and salinity control most species’ distributions. However, given the small sample size, it is unclear as to whether or not these factors are the main variables controlling the distribution of the mollusk fauna throughout the entire island.

This study has implications for interpreting climate change as reflected in mollusk community changes in sediment cores through time because mollusks have been shown to be reliable proxy indicators.