Scaphirhynchus Conference: Alabama, Pallid, and Shovelnose Sturgeon

St. Louis, Missouri, 11-13 January 2005

31.  ALABAMA STURGEON HABITAT IN THE ALABAMA RIVER:  INTEGRATION OF LABORATORY HABITAT SELECTION STUDIES AND FIELD MEASUREMENTS

Elise R. Irwin, USGS, Alabama Cooperative Fish and Wildlife Research Unit; 119 Swingle Hall, Auburn University, Auburn Alabama, 36849; Phone: 334-844-9190; E-mail: irwiner@auburn.edu

Gareth Turner, Alabama Cooperative Fish and Wildlife Research Unit, Auburn, Alabama.  turnegt@auburn.edu

Paul Hartfield, U. S. Fish and Wildlife Service, Jackson Field Office. 6578 Dogwood View Parkway, Suite A Jackson, Mississippi 39213.  paul_hartsfield@fws.gov

Richard Moreland, USGS, U.S. Geological Survey, 2350 Fairlane Drive, Montgomery, Alabama 36116.  rsmore@usgs.gov

Alabama sturgeon Scaphirhynchus suttkusi is one of the rarest fish in North America.  Despite significant attempts over the past decade to capture individuals for a rearing program, broodstock remain at large.  Because hydraulic units in rivers provide heterogeneity and, quite likely, specific habitats for shovelnose sturgeons, quantification of mesohabitats is a goal for conservation.  In addition, empirical evidence suggested that most historic sturgeon captures occurred in proximity to extensive mussel (Unionidae) beds.  We identified areas of the Alabama River within the known range of Alabama sturgeon and stratified our sampling efforts based on both historic sturgeon captures and location of mussel beds.  We used an Acoustic Doppler Current Profiler (ADCP) to measure depth and velocity at more than 40 sites below Miller’s Ferry and Claiborne dams.  We are in the process of comparing hydraulic units (as defined by ADCP transects and bathymetry) in the river with habitat selection (in terms of velocity) in laboratory studies conducted with shovelnose sturgeon S. platyorynchus.  Initial results indicate that we were able to mimic river velocities in the laboratory.  We are hopeful that these combined data will help in identification of suitable habitats for either target sampling regimes or conservation efforts.