Inks Reservoir - 2013 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 37-page report. For a copy of the complete report, use the download link in the sidebar.
Fish populations in Inks Reservoir were surveyed in 2013 using electrofishing and in 2014 using gill netting. Historical data are presented with the 2013-2014 data for comparison. This report summarizes the results of the surveys and contains a fisheries management plan for the reservoir based on those findings.
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.
Important sport fish include Largemouth Bass, White 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.
- Prey species: Gizzard Shad, Threadfin Shad, Bluegill, and Redbreast Sunfish were the predominant sources of forage. Threadfin Shad abundance increased significantly to compensate for low Gizzard Shad vulnerability.
- Catfishes: Channel and Blue Catfish were present in low-to-moderate density. Flathead Catfish were present in low abundance.
- Temperate basses: White Bass abundance declined significantly since the last survey, when record highs were documented. Poor tributary flows, caused by drought conditions might be the main cause for this decline. Striped Bass and Sunshine Bass were present in 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 to high numbers. Total catch rates and catch rates for fish 14 inches and greater increased, respectively, from the previous survey. Largemouth Bass growth rate remained similar since the last survey. Presence of trophy-size individuals adds a quality component to the fishery. Inks Reservoir also contained Guadalupe Bass.
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 Texas Parks and Wildlife Department (TPWD) Free Fishing in 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 2017/2018 sampling season. An additional gill netting survey should be conducted in spring 2016 to monitor White Bass abundance, if no significant flows are reestablished by then.
Performance Report as required by Federal Aid in Sport Fish Restoration Act Texas Federal Aid Project F-221-M-4 Inland Fisheries Division Monitoring and Management Program