Use of Side-Scan Sonar to Locate Tulotoma magnifica (Conrad, 1834) (Gastropoda: Viviparidae) in the Alabama River

Tulotoma magnifica is a federally threatened freshwater gastropod endemic to the Mobile Basin in Alabama. It was considered extirpated from the Alabama River until its rediscovery there in 2006. Tulotoma occurs primarily in colonies in large interstitial spaces beneath boulders and in bedrock crevices. We used side-scan sonar to identify boulder habitat in the Alabama River and to focus dive surveys at those sites. Eighty-five sites with potential Tulotoma habitat were identified with sonar and assessed by a diver. Colonies were found at five locations, three of which were previously unknown. Side-scan sonar greatly increased efficiency during this survey and was a useful tool.