Atlantic sturgeon marine distribution and habitat use along the northeastern coast of the United States

Though the distribution of Atlantic sturgeon Acipenser oxyrinchus is relatively well known in freshwater and estuarine habitats in the northern portion of their range, their distribution in marine habitats is poorly understood. Sturgeon migrate into marine waters to forage between spawning events and probably maintain gene flow between river populations by entering nonnatal river systems to spawn. While at sea, they are captured in commercial fishing gears. We investigated data collected by onboard fishery observers to determine the occurrence and habitat preference of Atlantic Sturgeon off the northeastern coast of the United States. Sturgeon distributions were based on monitored fishing trips over the period 1989-2000 and referenced to local bathymetry and sediment data. The results show that peak sturgeon Captures along the coast were approximately bracketed by isobaths ranging from 10 to 50 m. Sturgeon were present more frequently on gravel and sand sediment types and were associated with specific coastal features. The factors that may concentrate Atlantic sturgeon in particular coastal areas are discussed.