Nasworthy Reservoir - 2014 Survey Report
Prepared by Mandy K. Scott
Inland Fisheries Division - San Angelo District
This is the autho'rs summary from a 33-page report. For a copy of the complete report, use the download link in the sidebar.
Fish populations in Nasworthy Reservoir were surveyed in 2013 using gill netting, and in 2014 using electrofishing and trap netting. Historical data are presented with the 2014 data for comparison. This report summarizes the results of the surveys and contains a management plan for the reservoir based on those findings.
Nasworthy Reservoir is a 1,598-acre impoundment located on the southwestern edge of San Angelo, Texas in Tom Green County. It is a shallow, turbid reservoir with stable water levels and extensive emergent vegetation. Access is good with numerous public boat ramps and parks.
Important sport fish include Largemouth Bass, White Crappie, and Channel Catfish. Palmetto Bass (Striped Bass x White Bass hybrid) were stocked from the 1970s through 2007. Red Drum were once an important game species, but the discontinued operation of the power plant on Nasworthy Reservoir in 2003 eliminated this fishery that was dependent on the plant’s heated water effluent.
- Prey species: Gizzard Shad and Bluegill abundance increased in the most recent survey, and availability of shad to predators also increased. The prey base at Nasworthy Reservoir was in better shape than it had been in several years.
- Catfishes: Blue Catfish and Flathead Catfish were present in low abundance. Channel Catfish abundance was good, with many fish between 12 and 15 inches. Individuals up to 25 inches were sampled.
- Temperate basses: White bass were present in low abundance. Palmetto bass (hybrid striped bass) abundance declined and size structure increased since stockings were discontinued in 2007.
- Largemouth Bass: Largemouth Bass abundance was good. Size structure and body condition were not adequate, and growth to 14 inches was slow. An estimated 5,150 Largemouth Bass (> 6 inches) were in the reservoir, including approximately 800 bass > 14 inches.
- White Crappie: White Crappie catch rate was good, and consistent with previous years; however, more individuals > 10 inches were present in the latest survey. Growth to 10 inches was improved, with average 10-inch crappie being 2.5-years old.
Communicate with anglers, community groups, and city officials about the new Largemouth Bass regulation and how it will work to improve bass fishing. Communicate with the public about preventing spread of invasive species.
Performance Report as required by Federal Aid in Sport Fish Restoration Act Texas Federal Aid Project F-221-M-5 Inland Fisheries Division Monitoring and Management Program