Influence of Anchored Gillnets on Atlantic Sturgeon Bycatch and Behavior in Marine Waters

The sink-gillnets employed in the Goosefish (Lophius americanus) fishery are identified as a significant source of mortality for the federally endangered Atlantic Sturgeon (Acipenser oxyrinchus oxyrinchus). There is much concern within the fishing industry, that conservation measures to reduce both incidental take and mortality rates of sturgeon may be required.  During the spring of 2015, we deployed a VEMCO Positioning System (VPS) in Delaware’s coastal waters to assess behavior and interactions of telemetered Atlantic Sturgeon in the vicinity of three sink-gillnet treatments.  We fished two strings of gillnets 86 times for 2-4 hour intervals.  Each net was comprised of nine 91.4m panels tied to form a continuous string that were fished within the VPS boundaries and affixed with transmitters at the junction of individual panels to provide position estimates for individual treatments.  Atlantic Sturgeon landings were much greater in industry standard nets compared to lower profile and larger mesh experimental nets, providing evidence changes in net configuration may influence sturgeon behavior.  Over our approximately two month study we detected a large number of telemetered Atlantic Sturgeon (n=458) within our study boundaries.  Fine-scale position estimates will be examined to determine if interactions of Atlantic sturgeon occurred with each net treatment.