Lake Wood - 2003 Survey Report
Prepared by John Findeisen and Aaron Walters
Inland Fisheries Division
District 1-E, Mathis, Texas
This is the authors' summary from a 21-page report. For a copy of the complete report, use the download link in the sidebar.
Lake Wood (H-5) was surveyed in fall 2003 using trap nets and electrofishing and in spring 2004 using gill nets. This report summarizes the results of these surveys and contains a management plan for the reservoir based on those findings.
Lake Wood (448 acres) is located on the Guadalupe River in Gonzales County, and was constructed in 1931 by the Texas Hydroelectric Commission. Its main utility is for hydro-power production and recreational purposes. Angler and boat access is adequate with two public boat ramps, however there are no handicap-specific facilities at either location. At the time of sampling, habitat was primarily boat docks, rocks, floating-leaved vegetation, limited emergent vegetation, and stumps. Substrate included sand, clays, and deep loam soils. Nuisance aquatic vegetation, hydrilla and water hyacinth, have historically created access problems in the reservoir. A small stand of hydrilla was observed at the Guadalupe-Blanco River Authority (GBRA) park boat ramp in 2001, however, it was not observed in 2003. A small amount of water hyacinth was observed during the 2003 vegetation survey.
- Prey species: The 2003 electrofishing catch rates for gizzard shad was 126.0/h, substantially higher than was observed in 1997 (32.0) and 2001 (56.0). The Index of Vulnerability (IOV) indicated that 53% of the gizzard shad population is <8” and therefore vulnerable to predation. The 2003 electrofishing catch rate for bluegill and redear sunfish was 256.0/h and 30.0/h, respectively. The bluegill PSD (5), indicates the population is dominated by fish between 3 and 6 inches that are available to predation. An RSD-P of 9 for redear sunfish suggests potential for future quality fishery in this reservoir.
- Channel catfish: The 2004 gill net catch rate of channel catfish was 12.8/NN, higher than in previous years. Stock CPUE (8.8/NN) also increased. Growth rates indicated channel catfish reached legal size by age 2. Channel catfish as small as 8” and one year of age were collected, and thus providing evidence of reproduction and recruitment, an issue in the last report.
- Largemouth bass: The 2003 electrofishing catch rate for largemouth bass was 54.0/h, similar to 1997 and within the normal range for the reservoir. The range of relative weights (Wr) for largemouth bass between 8”-18” was approximately 85-110. A large number of substock-sized fish were caught, indicating a strong 2003 year class. Growth rates appeared to be adequate for juvenile fish, but inferences on the growth of legal size fish could not be made due to insufficient sample size. Electrophoresis indicated a 70% frequency of Florida largemouth bass alleles, with 17% of the population having the Florida largemouth bass genotype.
- White crappie: The 2003 trap net catch rate of white crappie was 13.4/NN, substantially higher than in previous years. Growth rates were good as white crappie reached legal size at 2 years of age.
- Based on current information, the reservoir should continue to be managed with existing regulations.
- The Guadalupe river system has produced trophy largemouth bass in the past. In Lake Wood, the Florida largemouth bass genotype was found in less than 20 percent of the largemouth bass sampled. Stock Florida largemouth bass at a rate of 100/acre.
- Hydrilla and water hyacinth have historically created access problems throughout the reservoir. Work with GBRA on controlling all nuisance aquatic vegetation before it becomes a problem.
- The littoral habitat appears to be limited, possibly limiting recruitment of largemouth bass. Work with GBRA and home-owner groups on habitat enhancement projects.
Performance Report as required by Federal Aid in Sport Fish Restoration Act Texas Federal Aid Project F-30-R-29 Statewide Freshwater Fisheries Monitoring and Management Program