Inks Reservoir - 2009 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 23-page report. For a copy of the complete report, use the download link in the sidebar.

Fish populations in Inks Reservoir were surveyed in 2009 using electrofishing and in 2010 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

Inks Reservoir is a 768-acre impoundment of the Colorado River. It was constructed in 1938 by the Lower Colorado River Authority (LCRA) for purposes of hydroelectric power, recreation and water supply. The reservoir lies within the Edwards Plateau eco-region, and its shoreline length is 20.5 miles. Inks Lake State Park borders the reservoir and provides access to approximately 30 percent of the shoreline. The remaining shoreline has either been developed by private property owners or is under control by the LCRA.

Management History

Important sport fish include white bass, largemouth bass, and catfish species. Recent management plans have recommended continuing monitoring populations under existing regulations. The Florida subspecies of largemouth bass was stocked in the reservoir in the late 80s and early 90s to increase Florida largemouth bass genetic influence in the population. Channel catfish have been stocked by the Inks Dam National Fish Hatchery through an agreement with the LCRA or when surplus fish become available.

Fish Community

• Prey species: Gizzard shad, threadfin shad, bluegill, and redbreast sunfish were the predominant sources of forage. Threadfin shad abundance declined from high’s recorded in the previous survey.
• Catfishes: Channel and blue catfish were present in low-to-moderate density. Flathead catfish were present in low abundance.
• Temperate basses: White bass were present in moderate numbers. Striped bass and sunshine bass were present in very low densities. Emigration from Lake Buchanan during flood releases is responsible for maintaining the striped and sunshine bass population in Inks Reservoir.
• Black basses: Largemouth bass were available in moderate numbers. Total catch rates and catch rates for fish 14 inches and greater doubled and tripled, respectively from the previous survey. Largemouth bass growth rate remained similar since the last survey. Inks Reservoir also contained Guadalupe bass.

Management Strategies

The reservoir should continue to be managed with existing fishing regulations. The largemouth bass, catfish and sunfish fisheries provide good opportunity for state park visitors. The TPWD free family fishing at state parks program is a great incentive to introduce new anglers to fishing. Efforts should be made to further promote fishing opportunities in this reservoir. General fish population monitoring with gill nets and electrofishing should be conducted in the 2013 sampling season. An aquatic vegetation survey should be conducted in summer 2010 to monitor the establishment of Eurasian watermilfoil, which was observed in the 2009 fall electrofishing survey.

Performance Report as required by Federal Aid in Sport Fish Restoration Act Texas Federal Aid Project F-30-R-35 Statewide Freshwater Fisheries Monitoring and Management Program