Choke Canyon Reservoir - 2013 Survey Report
Prepared by Greg Binion and John Findeisen
Inland Fisheries Division
District 1-E, Mathis, Texas
This is the authors' summary from a 40-page report. For a copy of the complete report, use the download link in the sidebar.
Fish populations were surveyed in 2013 using electrofishing and trap netting and in 2014 using gill netting to assess population trends for important sport fishes. Anglers were surveyed from 1 June 2013 to 31 May 2014. Historical data are presented with the 2013-2014 data for comparison. This report summarizes the survey results and contains a management plan for the reservoir based on those findings.
Choke Canyon is a 25,989-acre reservoir (averaged 14,393 acres in 2013-2014) located on the Frio River in the Nueces River Basin, approximately 80 miles south of San Antonio. Its main purposes are water supply and recreation (angling and pleasure boating). The reservoir has a history of substantial water level fluctuations. The substrate is composed primarily of silt, sand, clay, and some gravel/rock. Littoral habitat consisted of native aquatic vegetation, periodically flooded terrestrial vegetation, standing timber, and seasonally abundant water hyacinth and hydrilla.
Important sport fish species include Largemouth Bass, Blue and Channel Catfishes, White Bass, and White Crappie. Recent management efforts have focused on control of nuisance aquatic vegetation, compiling catch and harvest statistics on important sport fish species, documenting catch of trophy Largemouth Bass, and supplementing the naturally occurring Largemouth Bass population through stockings in 2009-2011 and 2013. The district has worked with the City of Corpus Christi to develop and implement a water hyacinth control program. District staff conducted herbicide treatments on water hyacinth in 2008 (195 acres), 2009 (80 acres), 2010 (525 acres) and 2011 (45 acres). Staff annually monitored access areas where hydrilla could restrict use. No vegetation control activities were needed in 2012 or 2013. Angler harvest of all sport fishes has been regulated according to statewide size and bag limits.
- Prey species: Gizzard and Threadfin shad and Bluegill formed the reservoirs forage base. Population size structure of prey species was suitable to support sport fish populations.
- Alligator Gar: Abundance and size structure of Alligator Gar was excellent. The population provided anglers the opportunity for trophy-sized catches.
- Catfishes: Blue Catfish abundance remained high. Channel and Flathead catfish were also present, but in low numbers. Blue Catfish size structure comprised a wide size-range of fish.
- White bass: Abundance and size structure of White Bass was poor in 2014; however, all fish collected were > 10 inches and thus available for angler harvest.
- Largemouth bass: Largemouth Bass relative abundance declined over the survey period. Mean age at legal length was 2.8 years. Largemouth Bass continued to be the most sought species in the reservoir. Numerous trophy-sized Largemouth Bass were caught and documented in creel surveys.
- Crappie: White Crappie was the predominant crappie species. Relative abundance, while low, was consistent with previous surveys.
- Continue to manage sport fish populations under existing harvest regulations.
- Conduct creel a survey to collect quantitative data on angler use.
- Continue to assist the City of Corpus Christi with the water hyacinth control program.
- Monitor access areas where hydrilla could restrict use.
- Discuss boat ramp improvements with controlling authorities.
- Stock Florida Largemouth Bass when water level increases.
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