San Augustine City Lake - 2010 Survey Report

Prepared by Dan Ashe and Todd Driscoll
Inland Fisheries Division
District 3-D, Jasper, Texas

This is the authors' summary from a 20-page report. For a copy of the complete report, use the download link in the sidebar.

Fish populations in San Augustine City Lake were surveyed in 2010 using electrofishing and trap netting and in 2011 using gill netting. A vegetation and access survey was conducted in 2010. This report summarizes the results of the surveys and contains a management plan for the reservoir based on those findings.

Reservoir Description

San Augustine City Lake is an impoundment of Carrizo and Caney Creeks. The City of San Augustine is the reservoir’s controlling authority. Primary uses are water supply and recreation. This reservoir has a surface area of 200 acres, a shoreline length of 5.5 miles, and a mean depth of 10 feet. Water level fluctuations average 3 feet annually. Boat and bank access is adequate, with one boat ramp present.

Management History

Important sport fish include largemouth bass, white and black crappie, and catfish. The management plan from the 2002 survey report included changing the 18-inch minimum length limit for largemouth bass to a 14- to 18-inch slot-length limit. The slot-length limit was implemented in 2004. Based on 2010 electrofishing results, the slot-length limit has not had any detectable affect on increasing the numbers of 14- to 18-inch largemouth bass. Sportfish body condition was adequate but prey fish abundance was less than desired. Hydrilla has been problematic over the years, covering approximately 75% of the reservoir surface area in 2002. From 2002-2003, triploid grass carp were stocked at a rate of 4/vegetated-acre (600 fish total) in an attempt to reduce hydrilla coverage to 10-15%. Since these stockings, coverage steadily declined, and no hydrilla has been observed since 2007.

Fish Community

• Prey species: Threadfin and gizzard shad were present in the reservoir but abundance was low. Electrofishing catch of sunfish was moderate and comprised mostly of bluegill, redbreast, and redear sunfish with few fish over 6 inches in length.
• Catfishes: Numbers of channel catfish have improved, indicating increased recruitment and/or survival. Channel catfish abundance likely increased due to the elimination of hydrilla. This change likely resulted in nutrient shifts favoring channel catfish prey abundance. Largemouth bass recruitment has also declined since hydrilla disappeared, reducing predation on channel catfish and leading to an increase in abundance.
• Largemouth bass: Largemouth bass were moderately abundant. Size structure has remained consistent from past surveys with most fish <15 inches in length. Largemouth bass were in moderate condition. The current largemouth bass water body record is 13.13 lbs set in March 2006.
• Crappies: Relative abundance and size structure of white crappie was good. Growth rates for white crappie were good with most fish reaching legal size in 2.0 years, but body condition was poor. Only white crappie was observed, but black crappie had been collected in the past.

Management Strategies

• Continue to manage largemouth bass with a 14- to 18-inch slot length limit.
• Continue to monitor for re-occurrence of hydrilla through annual aquatic vegetation surveys.
• Conduct electrofisher, trap net, gill net, and access surveys in 2014 and 2015.
• Conduct annual aquatic vegetation surveys (2011-2014).

Performance Report as required by Federal Aid in Sport Fish Restoration Act Texas Federal Aid Project F-221-M-1 Statewide Freshwater Fisheries Monitoring and Management Program