Timpson Reservoir - 2007 Survey Report

Prepared by Dan Ashe and Todd Driscoll
Inland Fisheries Division
District 3-D, Jasper, Texas

This is the authors' summary from a 19-page report. For a copy of the complete report, use the download link in the sidebar.

Fish populations in Lake Timpson were surveyed in 2007 using fall electrofishing and trap nets and in 2008 using gill nets and spring electrofishing. A vegetation and access survey was conducted in 2007. This report summarizes the results of the surveys and contains a management plan for the reservoir based on those findings.

Reservoir Description

Lake Timpson is located in Shelby County. The Shelby County Freshwater Supply District is the controlling authority. Primary uses are water supply and recreation. This reservoir has a surface area of 223 acres, a shoreline length of 8 miles, and an average depth of 8 feet. Water level fluctuations average 1-3 feet annually. Boat and bank access is adequate, with one boat ramp present.

Management History

Important sport fish included largemouth bass, crappie, and catfish. Prior to 1994, largemouth bass were managed under statewide regulations. In 1994 largemouth bass regulations were changed to a 14- to 21-inch slot length limit. Electrofishing data indicated the slot length limit had the desired effect of producing increased numbers of largemouth bass within the protective slot-length limit. Growth rates of largemouth bass were good with fish growing into the protective slot-length limit between age 2 and age 3. Hydrilla was first documented in Lake Timpson in 2003, and has the potential to become highly problematic given the average depth of the lake. Triploid grass carp were stocked in 2004 at a rate of 5 fish/vegetated acre (448 fish total) in an attempt to reduce hydrilla coverage to 10-15%. Since these stockings, hydrilla coverage has steadily declined with virtually no hydrilla coverage observed during the summer of 2007.

Fish Community

• Prey species: Threadfin shad were present in the reservoir. Electrofishing catch rates of bluegill and redear sunfish were high. Good numbers of 6- to 8-inch redear sunfish were also present. Other prey species included redbreast sunfish, warmouth, and spotted sunfish.
• Catfishes: Blue catfish and channel catfish were present in the reservoir. Blue catfish were stocked in 1998, but no fish less than 30 inches were caught during 2008 gill netting, indicating no natural reproduction. Channel catfish catch was also low indicating poor reproduction.
• Largemouth bass: Largemouth bass were relatively abundant. Population size structure from recent surveys indicated the protective slot-length limit had the desired effect, with an abundance of largemouth bass within the protective slot-length limit available for angler catch. Largemouth bass exhibited good growth rates and were in average condition.
• Crappies: The abundance of crappies during the 2007 trap netting survey was high, with good numbers of legal-length (> 10 inches) fish observed. Both white and black crappies were present with black crappie being the dominant species.

Management Strategies

• Continue to manage largemouth bass with a 14- to 21-inch slot length limit.
• Continue to monitor trends of hydrilla coverage through annual aquatic vegetation surveys.
• Conduct electrofishing (spring and fall), trap netting, and gill netting surveys in 2011 and 2012, respectively.
• Conduct access and structural habitat surveys in 2011.

Performance Report as required by Federal Aid in Sport Fish Restoration Act Texas Federal Aid Project F-30-R-33 Statewide Freshwater Fisheries Monitoring and Management Program