James P. Kirk

We explored the feasibility of sampling young-of-year (yoy) Gulf sturgeon (Acipenser oxyrinchus desotoi) in the Apalachicola River, Florida, using modified balloon trawls during January and June 2009. Three yoy sturgeon (57 - 120 mm TL) were captured during June 2009 in the lower reaches of the river system. Initially, this method of assessment is labor intensive and may require more than 25 river kilometers (rkm) of trawling per capture. While this gear type has been remarkably efficient for sampling yoy Scaphirhynchus (i.e., pallid and shovelnose sturgeon) in the Mississippi River...

Upstream migration of the Cooper River, South Carolina, population of shortnose sturgeon (Acipenser brevirostrum) is severely limited at Pinopolis Dam (river km 77). Shortnose sturgeon congregating and spawning in the tailrace of the dam has been documented but data is lacking on the group's population dynamics. From 1995 through 1999, the population was sampled in the tailrace with 91.4 m long bottom-set gillnets during the spawning season when fish were concentrated in the area. Fish captured during 1996-1998 were tagged for a multiple census mark-recapture population estimate using the...

Shortnose sturgeon (Acipenser brevirostrum) were monitored as part of continuing studies in the Ogeechee and Canoochee rivers adjacent to Fort Stewart, Georgia, during 1999 and 2000. Over 13,000 net-meter h soak time and 1,700 person h of effort were expended; short (27.5-m) experimental gill nets were a satisfactory sampling gear. Retention of externally mounted telemetry tags was poor (mean = 80 d), and spawning habitats were not located. The population, ranging from ages 3 to 14, was estimated at 147 individuals. Growth equation parameters and rates of mortality were similar to those...

Studies in large and small ponds conducted on the Auburn University Fisheries Research Station from 1981 through 1983 suggest that gizzard shad (Dorosoma cepedianum) severely competed with largemouth bass (Micropterus salmoides) and bluegill (Lepomis macrochirus) populations. Gizzard shad introductions lowered bluegill reproductive success and caused an imbalance the first year of introduction. Gizzard shad grew rapidly through the size range where they were vulnerable to largemouth bass predation; in this 3-year study, largemouth bass were unable to control gizzard shad numbers. Within 2...