Casa Blanca Reservoir - 2014 Survey Report

Prepared by John Dennis and Randy Myers
Inland Fisheries Division - San Antonio District

This is the authors' summary from a 26-page report. For a copy of the complete report, use the download link in the sidebar.

Fish populations in Casa Blanca Reservoir were surveyed in 2014 using electrofishing and in 2015 using gill nets. Sampling strategy changed from standardized sampling to objective based sampling in the 2014-2015 sampling year. Historical data are presented with the 2014-2015 data for comparison. This report summarizes survey results and contains a management plan for the reservoir based on those findings.

Reservoir Description

Casa Blanca is a 1,055 acre reservoir located near Laredo, Texas, in the Rio Grande River watershed. In 1990, the county park located on the lower end of the reservoir was acquired by Texas Parks and Wildlife (TPW) and opened in March of 1991 as Lake Casa Blanca International State Park. Major uses include recreation and irrigation for a golf course. The reservoir has a history of substantial water level fluctuation. Angler and boat access is very good. A little less than half of the shoreline was rocky or gravelly, and aquatic plants and flooded terrestrial vegetation occupied about 50% of the reservoir in 2013 and 2014. Considerable shoreline access, including a fishing pier, exists for bank angling.

Management History

Important sport fishes include Largemouth Bass, catfishes, and hybrid striped bass. Harvest of all sport fish species except Largemouth Bass has been regulated according to statewide size and daily bag limits. Largemouth Bass harvest is currently regulated with an 18-inch minimum size limit (implemented in 1994). Palmetto bass have been stocked regularly with stockings occurring in seven years since 2004. In 2014, sunshine bass were stocked instead of palmetto bass. Florida Largemouth Bass fingerlings were last stocked in 2011. ShareLunker fingerlings were stocked in 2006, 2008, and 2010.

Fish Community

• Prey species: Gizzard Shad and Bluegill were the primary forage species. Gizzard Shad abundance was high and most were suitably sized for forage. Bluegill were present in sufficient quantity and size to support predator species. Other prey species were also present in adequate numbers.
• Catfishes: Abundance of Blue and Channel catfishes was good; however, the populations were dominated by small fish. Flathead Catfish continue to exist in the reservoir.
• Hybrid striped basses: Hybrid striped bass abundance was good. Fish up to 23 inches were collected and fish grew rapidly.
• Largemouth Bass: Largemouth Bass abundance was good, including numerous fish above the 18-inch minimum length limit. They grew to 14 inches in less than two years.
• Crappies: White and Black crappies continued to exist in the reservoir.

Management Strategies

Continue to manage fisheries with current regulations. Stock hybrid striped bass annually at the rate of 15 fingerlings per acre. Collect angler utilization data. Fishes will be sampled every four years according to the objective based sampling plan.

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