Buchanan Reservoir - 2011 Survey Report

Prepared by Marcos J. De Jesus and Mukhtar Farooqi
Inland Fisheries Division
District 2-C, San Marcos, Texas

This is the authors' summary from a 58-page report. For a copy of the complete report, use the download link in the sidebar.

Fish populations in Lake Buchanan were surveyed in 2011 using electrofishing and in 2012 using gill nets. This report summarizes the results of the surveys and contains a fisheries management plan for the reservoir based on those findings.

Reservoir Description

Lake Buchanan is a 22,211-acre impoundment of the Colorado River located in Burnet and Llano counties. It was constructed in 1937 by the Lower Colorado River Authority (LCRA) for purposes of hydroelectric power, water supply, flood control, and recreation. The reservoir lies within the Edwards Plateau ecological area. Its drainage area is approximately 31,250 square miles. Shoreline length is approximately 140.6 miles. Only small amounts (<1 acre) of aquatic vegetation have ever been documented in the reservoir.

Management History

Important sport fish include white bass, striped bass, sunshine bass, largemouth bass, and catfish species. The management plans for 2007 were to: continue annual stockings of striped bass; monitor the striped bass population with additional gill netting; and, permit the stocking of sunshine bass by the Lake Buchanan Conservation Corporation (LBCC). Striped bass have been stocked almost annually since 1977, and the reservoir is regarded as one of the best striped bass fisheries in Texas. Sunshine bass were first stocked in 2006 by the LBCC. The Florida subspecies of largemouth bass was stocked in the reservoir in the late 1970s and once again in 2008 to increase Florida largemouth bass genetic influence in the population. Blue catfish were stocked in 1989 and 1990 to help establish a sustainable population. White bass were managed under an experimental 12-inch minimum length limit from 1995 to 2003. The regulation was rescinded after analysis indicated environmental factors, not angler harvest, were probably more influential in determining white bass population density.

Fish Community

• Prey species: Gizzard shad, threadfin shad, redbreast sunfish and bluegill were the predominant sources of forage.
• Catfishes: Blue catfish surpassed channel catfish as the predominant catfish species present in our surveys. Flathead catfish were present in low densities.
• Temperate basses: White bass abundance decreased in 2012, but still remained moderate. Striped bass gill net average catch slightly decreased since 2008, remaining below historical average. Stress due to high water temperature and low dissolved oxygen in the summer months may be causing decreased body condition and growth of striped bass. Sunshine bass showed an increasing trend in abundance, with many legal-size (≥18 inches) individuals present.
• Black basses: Largemouth bass catch decreased noticeably in 2011, most likely a reflection of record-low water levels at the time of survey. Largemouth bass reach 14 inches by age 2.

Management Strategies

The reservoir should continue to be managed with existing fishing regulations. It is still uncertain if sunshine bass are out-performing striped bass, especially during thermally stressful summer months. Further catch evaluations should be conducted before considerations are taken to shift to stocking solely hybrid striped bass into Buchanan Reservoir. Sunshine bass should continue to be allowed for stocking to supplement the Morone fishery, especially since recent state hatchery production has been hindered by natural causes. Gill netting should be conducted annually to monitor Morone spp. abundance.

Performance Report as required by Federal Aid in Sport Fish Restoration Act Texas Federal Aid Project F-221-M-2 Statewide Freshwater Fisheries Monitoring and Management Program