Scaphirhynchus Conference: Alabama, Pallid, and Shovelnose Sturgeon

St. Louis, Missouri, 11-13 January 2005

8.  PROPAGATION OF PALLID STURGEON FROM THE OLD RIVER CONTROL COMPLEX, LOUISIANA

Jan C. Dean, Natchitoches National Fish Hatchery, 615 South Drive, Natchitoches, LA 71457: Phone 318-352-5324; FAX 318-352-8082; jan_dean@fws.gov

Bobby C. Reed, Louisiana Department of Wildlife and Fisheries, 1213 North Lakeshore Drive, Lake Charles, LA 70601; Phone 337-491-2577; FAX 337-491-2009; breed@wlf.louisiana.gov

Efforts to study and recover the Old River Control Complex (ORCC) pallid sturgeon population began in the mid 1990s.  Over 300 pallid sturgeon Scaphirhynchus albus, and almost 2000 overall river sturgeon of genus Scaphirhynchus, have been collected from the ORCC from fall 1997 through spring 2004 by coordinated efforts of the Louisiana Department of Wildlife and Fisheries (LDWF) and the Natchitoches National Fish Hatchery (NNFH).  Other river sturgeon in collections there include the shovelnose sturgeon S. platyrynchus and the putative hybrid between pallid and shovelnose sturgeon.  The ORCC includes two U.S. Army Corps of Engineer water control structures which can be opened to release water from the Mississippi River through an outflow channel to the Atchafalaya River and eventually to the Gulf of Mexico.  The Atchafalaya River is the primary distributary for the Mississippi River, and the ORCC is the main control point for these water releases.  The greater ORCC area also includes a hydroelectric plant and a lock for barge traffic between the Mississippi, Red and Atchafalaya rivers.  Thus, the ORCC pallid sturgeon population is an open population.

One female and one male pallid sturgeon collected from the ORCC in late 1997 were spawned successfully at the NNFH in March 1998, and the resultant young were stocked back at the ORCC site in October 1998.  That successful first year resulted in the need to modify two existing buildings at NNFH to hold adult and to rear young pallid sturgeon.  There was only sporadic and limited spawning success during the spring seasons from 1999 through 2003 due largely to the inability to capture suitable brood fish. However, information was gained during that time regarding the size, genetics, morphometrics, anomalies, vocalizations, erythrocyte genome size, blood cell counts, blood chemistry profiles, presence of iridovirus, food habits, biochemistry of yolk development, and the evaluation of cryopreserved sperm for the ORCC sturgeon.

The most successful spawning of the ORCC pallid sturgeon occurred in May 2004.  Water flows and temperatures were optimum, and several suitable brood fish were collected.  The resultant young were reared initially at Natchitoches National Fish Hatchery, though they quickly exceeded the available tank space.  Most of the fingerlings were reared at the Booker-Fowler State Fish Hatchery near Woodworth, Louisiana.  Stocking sites include the ORCC area and four areas adjacent to the Mississippi River.   Growth rates for young pallid sturgeon were excellent.