Lyndon B. Johnson Reservoir - 2008 Survey Report

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

This is the authors' summary from a 31-page report. For a copy of the complete report, use the download link in the sidebar.

Fish populations in Lake Lyndon B. Johnson (LBJ) were surveyed in 2008 using electrofishing and trap nets, and in 2009 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 LBJ is a 6,502-acre impoundment of the Colorado and Llano Rivers in Burnet and Llano counties. It was constructed in 1951 by the Lower Colorado River Authority (LCRA) for purposes of hydro-electric and steam-electric power, flood control, and water conservation. Lake LBJ has a drainage area of approximately 36,290 square miles and a shoreline length of about 154 miles. Residential and commercial properties border most of the shoreline area.

Management History

Important sport fish include white bass, largemouth bass, and catfish species. Fisheries management plans for 2005 were to: monitor largemouth bass and prey populations in regard to their response to vegetation expansion within the reservoir; monitor aquatic vegetation due to potential expansion of exotic invasive species; and to evaluate the progress of planted beneficial aquatic vegetation. Prior management activities included fingerling Florida largemouth bass stockings in 2001 and 2002 to improve the potential for trophy largemouth bass. The lake has always been managed under statewide regulations.

Fish Community

• Prey species: Gizzard shad, bluegill, and redbreast sunfish were the predominant sources of forage. Threadfin shad were also available in low density.
• Catfishes: Channel catfish was the predominant catfish species, but present in low densities. Flathead and blue catfish were also present in low densities.
• Temperate basses: White bass were present in low density.
• Black basses: Largemouth bass were relatively abundant. Size structure was good, with 52% of the adult bass exceeding 14 inches in 2008. Largemouth bass growth was moderate. On average individuals exhibited sub-optimal body condition. Guadalupe bass were also present.

Shoreline Habitat

The majority (88%) of the shoreline was comprised of bulkhead (51%) and vegetated bank (37%). Bulkheading has decreased the quality of shoreline fish habitat.

Management Strategies

The reservoir should continue to be managed with existing fishing regulations. Shoreline habitat continues to be negatively affected by bulkheading, and the controlling authority and homeowners should be made aware of the importance of shoreline habitat to the largemouth bass fishery. A vegetation and shoreline habitat survey should be conducted in 2011. Routine gill netting, trap netting and electrofishing surveys should be conducted in 2012–2013.

Performance Report as required by Federal Aid in Sport Fish Restoration Act Texas Federal Aid Project F-30-R-34 Statewide Freshwater Fisheries Monitoring and Management Program