Developing Hydroacoustic Methods for the Study of Sturgeons and Other Large-Bodied Fishes

Hydroacoustic technologies are being used increasingly in fisheries research and management.  Perhaps the fastest growth has been in the use of side-scan sonar.  While often used to survey substrate and bottom characteristics, it is possible to detect fish using this technology.  The goal of our study is to develop methodologies to study sturgeon Acipenser spp. populations using side-scan sonar to replace or supplement traditional sturgeon sampling and surveying methods that require the use of gill nets.  Detrimental effects of netting and associated handling is an issue for species of concern, such as Atlantic sturgeon A. oxyrhinchus and shortnose sturgeon A. brevirostrum.  Results of our preliminary trials demonstrate that we can detect fish and can possibly identify larger individuals to genus.  Future work will consist of developing detection probability estimates for side-scan sonar and creating a standardized survey methodology, likely based on an occupancy framework.