Austin Reservoir - 2008 Survey Report

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

This is the authors' summary from a 26-page report. For a copy of the complete report, use the download link in the sidebar.

Fish populations in Austin Reservoir were surveyed using electrofishing in 2008 and gill nets in 2009. This report summarizes the results of the surveys and contains a fisheries management plan for the reservoir based on those findings.

Reservoir Description

Austin Reservoir is a stable level 1,599 acre riverine type impoundment of the Colorado River located in the heart of the City of Austin (COA). It was constructed in 1893 for purposes of hydro-electric power, municipal water supply, water conservation and recreation. The reservoir is used to pass water from Travis Reservoir downstream. The reservoir is operated by the Lower Colorado River Authority (LCRA) and COA. The reservoir lies within the Edwards Plateau vegetational area and has a drainage area of approximately 38,240 square miles. Land surrounding the reservoir is highly developed with commercial and residential property bordering most of the shoreline.

Management History

Important sport fishes include largemouth bass and catfishes. Fingerling Florida sub-species of largemouth bass were last stocked in Austin Reservoir in 2007. ShareLunker offspring (advanced size fingerlings) were stocked in 2008. These are offspring of largemouth bass donated to the TPWD ShareLunker program. In order to qualify for the ShareLunker Program largemouth bass must weigh at least 13 pounds. Triploid grass carp (12,800) were stocked by the City of Austin from 2003 to 2007 in an attempt to control the aquatic plant hydrilla.

Fish Community

• Prey species: Bluegill, redbreast sunfish, gizzard shad and threadfin shad were the dominant prey species available.
• Catfishes: Channel, blue and flathead catfish were present in low density.
• Largemouth bass: Largemouth bass were abundant. Almost all angling effort (91%) on the reservoir was directed towards largemouth bass (Smith et al. 2002). Lake Austin is considered one of Texas’ best trophy largemouth bass fisheries. Since 1994 seven largemouth bass weighing 13 pounds or greater caught by anglers were documented by TPWD. The most recent documented catch of a largemouth bass exceeding 13 pounds was in 2007.

Management Strategies

Based on current information, the reservoir should continue to be managed with existing harvest regulations. Aquatic vegetation coverage, including hydrilla, typically varies each year and should be monitored annually. Aquatic plant coverage may help explain trends in largemouth bass abundance. Electrofishing surveys should be conducted annually to measure largemouth bass abundance.

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