Choke Canyon Reservoir - 2007 Survey Report
Prepared by John Findeisen and Greg Binion
Inland Fisheries Division
District 1-E, Mathis, Texas
This is the authors' summary from a 32-page report. For a copy of the complete report, use the download link in the sidebar.
Fish populations at Choke Canyon Reservoir were surveyed in fall 2007 using trap nets and electrofishing, and in 2008 using gill nets to assess population trends for important sport fish communities. A creel survey was conducted. This report summarizes the results and contains a management plan for the reservoir based on those findings.
Choke Canyon is a 25,989-acre reservoir (averaged 25,623 acres in 2007-2008) located on the Frio River in the Nueces River Basin, approximately 80 miles south of San Antonio. Its main utilities are water supply and recreational opportunities including angling and pleasure boating. The reservoir has a history of substantial water level fluctuations. Habitat consisted of standing timber and colonies of native and exotic vegetation.
Important sport fish species included blue and channel catfish, largemouth bass, white bass, and white crappie. Since the previous report, northern largemouth bass were stocked as part of a research project. Water hyacinth became an issue on this reservoir in 2006. Herbicide treatments on water hyacinth were conducted in both 2006 (25.5 acres) and 2007 (174.5 acres). The 2004 management plan focused on monitoring hydrilla, publicizing improving fisheries, and removing the annual creel survey. District staff annually monitored access areas where hydrilla could restrict use. District staff publicized the fisheries through written press releases and telephone interviews. The creel survey was moved to Coleto Creek Reservoir from June 2005 through May 2006 but returned to Choke Canyon beginning in September 2006.
- Prey species: Gizzard shad relative abundance steadily decreased and the majority of individuals generally were too large for most predators. Threadfin shad, bluegill, and redear sunfish populations were mostly comprised of sizes available to most predators. Body condition of most predator species indicated no problem with forage availability.
- Catfishes: Blue catfish were the predominant catfish species in the reservoir, and targeted by most catfish anglers. Channel catfish provided a fishery as suggested by the creel survey data despite relatively low catch rates in gill net surveys. Flathead catfish were present in the reservoir but were rarely encountered in gill net and creel surveys.
- White bass: White bass were numerous in the reservoir and sought by many anglers, especially during the spring spawning run. Catches of white bass exceeding 18-inches in length have been documented from this reservoir.
- Largemouth bass: Largemouth bass were the most sought species in this reservoir. Numerous largemouth bass over 8 pounds were caught by anglers and reports of bass over 10 pounds were frequent. The electrofishing catch rate of largemouth bass decreased in 2007; however, this was expected as the reservoir water level increased 6.5 ft from the previous year, likely spreading out the population.
- Crappies: White crappie were the predominant crappie species. Despite decreasing trap net catch rates of crappie, angler catch rates for white crappie increased.
- Continue to manage the sport fisheries under existing harvest regulations.
- Continue to work with the city of Corpus Christi on controlling water hyacinth.
- Continue to monitor access areas where hydrilla could restrict use.
- Implement a trophy largemouth bass reporting program.
Performance Report as required by Federal Aid in Sport Fish Restoration Act Texas Federal Aid Project F-30-R-33 Statewide Freshwater Fisheries Monitoring and Management Program