O.H. Ivie Reservoir - 2009 Survey Report

Prepared by Mukhtar Farooqi, Mandy K. Scott, and *Craig Bonds
Inland Fisheries Division
District 1-C, San Angelo, Texas
* Region 3 Office, Tyler, Texas

This is the authors' summary from a 37-page report. For a copy of the complete report, use the download link in the sidebar.

Fish populations in O. H. Ivie Reservoir were surveyed annually from 2006 to 2009 using electrofishing, in 2009 using trap nets, and in 2010 using gill nets. A creel survey was conducted from June 2009 to May 2010. This report summarizes the results of the surveys and contains a management plan for the reservoir based on those findings.

Reservoir Description

O. H. Ivie Reservoir is a 19,200-acre impoundment, when full, and is located on the Colorado and Concho rivers in Concho, Runnels, and Coleman counties, Texas, approximately 55 miles east of San Angelo. Water level declined 26 feet from May 1998 to November 2004. Subsequent rainfall led to increases in water level in 2005 and 2007; the reservoir was approximately 21 feet below conservation pool at the time of fall sampling. In May 2010, reservoir surface area totaled 10,675 acres. Habitat features consisted of standing timber, rocks, flooded saltcedar, native submerged aquatic plants, and hydrilla.

Management History

Important sport fish included largemouth bass, white bass, white crappie, and catfishes. The management plan from the 2005 survey report included annual electrofishing and creel surveys to evaluate the effectiveness of the 2001 largemouth bass length limit change (from 18-inch minimum length and 5-fish bag to a 5-fish bag, 2 of which may be <18 inches) and annual aquatic vegetation surveys primarily to monitor changes in hydrilla coverage. The purpose of the largemouth bass regulation change was to increase growth rates of 14- to 18-inch fish by reducing stockpiling through increased angler harvest. A variety of fish species have been stocked in the reservoir including threadfin shad, bluegill, channel, blue and flathead catfishes, Florida largemouth bass, smallmouth bass, white crappie, and walleye. Walleye stockings were discontinued after failing to produce a fishery.

Fish Community

• Prey species: Threadfin shad are present in the reservoir. Electrofishing catch of gizzard shad was higher than in previous years, and approximately one third were available as prey to most sport fish. Electrofishing catch of bluegill was low, but overall size structure was similar to previous years. Bluegill up to 10 inches were caught by anglers.
• Catfishes: Blue catfish continue to offer a very low-density rod-and-line fishery. The channel catfish population offered a broad size range and greater abundance than blue catfish, attracting greater angling pressure and harvest. Flathead catfish were present in low numbers.
• White bass: White bass were moderately abundant and the second most targeted fish by anglers; although they only accounted for <5% of directed angler effort. Angling catch rate was lower than in previous years, but harvest was substantially higher.
• Largemouth bass: Largemouth bass were less abundant than in previous years; although there were some larger fish present. Most largemouth bass were in fair condition. The majority of anglers targeted largemouth bass, and the percentage of legal-size fish released was high. Tournament anglers accounted for 24.5% to 61.3% of directed effort from June 2006 to May 2010.
• Smallmouth bass: Very few smallmouth bass have been collected in recent surveys and few anglers targeted them. However, anglers have reported catching low numbers when interviewed in recent creel surveys.
• White crappie: Abundance of harvestable-size white crappie remained low; however, angler catch rates have increased over the past four years. Crappie were the third most targeted species, but directed angler effort was <4%.

Management Strategies

• Conduct annual creel, electrofishing, and aquatic vegetation surveys 2010-2014.
• Conduct trap net surveys in 2011 and 2013.
• Conduct gill net survey in 2014.

Performance Report as required by Federal Aid in Sport Fish Restoration Act Texas Federal Aid Project F-30-R-35 Statewide Freshwater Fisheries Monitoring and Management Program