Gulf Sturgeon Movements in the Pearl River Drainage and the Mississippi Sound

A study of the seasonal movements of Gulf sturgeon Acipenser oxyrinchus desotoi was conducted in the Pearl River system and the Mississippi Sound from 2000 through 2003. We captured or recaptured, marked, and released 503 Gulf sturgeon, 98 adults being tagged with internal or external telemetry tags. Movement chronologies were generally similar to those reported in other studies. Summer habitats were found in the Pearl and Bogue Chitto rivers (Louisiana–Mississippi), and these habitats were occupied from April through November. Adults and subadults were spatially separated, the adults being concentrated in the Bogue Chitto River and the subadults in the Pearl River. Tagged adults began to leave the summer habitat during September and to arrive at the mouth of the Pearl River and the Rigolets Pass. The last departure from this location was in late November. Wintering habitat between Cat, Ship, Horn, and Petit Bois islands in the Mississippi Sound was used between November and early March. Gulf sturgeon returned to the Rigolets Pass from March through June. Despite extensive sampling and the use of multiple collection gears, no eggs, larvae, or age‐0 fish were captured and Gulf sturgeon spawning sites within this system remain unknown. The identification of summer and wintering habitats is essential for critical habitat designation for this species, which is federally listed as threatened.