Austin Reservoir - 2020 Survey Report

Prepared by Marcos J. De Jesus and Muhktar Farooqi
Inland Fisheries Division
San Marcos/Austin District

This is the authors' summary from a 35-page report. For a copy of the complete report, use the download link in the sidebar.

Fish populations in Austin Reservoir were surveyed in 2020 by using electrofishing. This report summarizes the results of the survey and contains a fisheries management plan for the reservoir based on those findings. Historical data are presented with the 2017-2020 data for comparison. This report summarizes the results of the surveys and contains a management plan for the reservoir based on those findings.

Reservoir Description

Austin Reservoir is a stable-level 1,589-acre riverine-type impoundment of the Colorado River located in the heart of the City of Austin (COA). It was constructed in 1893 for hydro-electric power, municipal water supply, water conservation and recreation. The reservoir is used to pass water downstream from Travis Reservoir. The reservoir is operated by COA and the Lower Colorado River Authority (LCRA). The reservoir lies within the Edwards Plateau and has a catchment area of approximately 38,240 square miles. Land surrounding the reservoir is highly developed with commercial and residential property bordering most of the shoreline. Natural habitat features consisted of boulders and emergent aquatic plants.

Management History

Important sport fish include Largemouth Bass. The 2016 management plan included stocking Florida Largemouth Bass to maintain high genetic influence and managing invasive levels of hydrilla. Largemouth Bass have been managed under statewide regulations. Other species of interest are Common Carp and Smallmouth Buffalo; the reservoir has been promoted as a prime destination for bank anglers pursuing these species. The triploid Grass Carp permit was lifted in 2016 to allow harvest and help restore aquatic vegetation in the reservoir.

Fish Community

• Prey species: Gizzard Shad, Threadfin Shad, Redbreast Sunfish, and Bluegill were the predominant sources of forage.
• Catfishes: Blue Catfish, Channel Catfish, and Flathead Catfish have historically been present in low densities.
• Temperate basses: White Bass have historically been present in low densities. Striped Bass have been present in very low densities due to emigration from Travis Reservoir during flood events.
• Largemouth Bass: Largemouth Bass were moderately abundant. Previous creel surveys showed almost all angling effort is directed towards Largemouth Bass. Austin Reservoir was considered one of Texas’ best trophy Largemouth Bass fisheries. Since 1994, anglers have submitted 21 Largemouth Bass weighing 13 pounds or greater to the Texas Parks and Wildlife Department (TPWD) ShareLunker Program. The most recent entry was in January 2021; almost 6 years after the previous entry in 2014. Since 2014, the depletion of aquatic vegetation habitat has impacted catch of trophy-size bass.
• Guadalupe Bass: Guadalupe Bass have been present in low densities. Seven Guadalupe Bass ranging from 3-12 inches were collected in 2020.
• Crappie: Black Crappie and White Crappie have been historically present in low densities.
• Rough fishes: Common Carp, Smallmouth Buffalo, and Freshwater Drum are present in moderate densities and provide recreational angling opportunities for bank anglers. Austin Reservoir is known to consistently produce trophy-size specimens of these species, which attracts bank anglers who direct their efforts towards a catch-and-release experience.

Management Strategies

• The reservoir should continue to be managed with existing harvest regulations.
• Efforts to restore quality bass fishing by restoring aquatic habitat should be pursued.
• Encourage the removal of triploid Grass Carp. Continue to conduct annual electrofishing surveys to measure Largemouth Bass abundance as it relates to aquatic vegetation coverage.
• When habitat is restored, continue Florida Largemouth Bass stockings to maintain optimal genetic influence and trophy potential for this population.
• Educate angler groups about lake vegetation management and encourage them to support a “balanced” management approach. Continue efforts to create awareness and educate people about invasive species.

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