Possum Kingdom Reservoir - 2018 Survey Report

Prepared by Tom Lang and Robert Mauk
Inland Fisheries Division - Wichita Falls District

This is the authors' summary from a 28-page report. For a copy of the complete report, use the download link in the sidebar.

Fish populations in Possum Kingdom Reservoir were surveyed in 2018 using electrofishing and with gill netting in 2019. Historical data are presented with the 2018-2019 data for comparison. This report summarizes the results of the surveys and contains a management plan for the reservoir based on those findings.

Reservoir Description

Possum Kingdom Reservoir is a 15,588-acre impoundment located on the Brazos River approximately 76 miles west of Fort Worth. It has a primarily rocky shoreline with many boat docks. The reservoir was within 2 feet of conservation pool (1,000 ft. above mean sea level) during the survey year. Due to prolonged drought, the reservoir water level had decreased to 15 feet below conservation pool. However, in May 2015 substantial rainfall filled Possum Kingdom to near capacity.

Management History

Important sport fish populations include catfish spp., White Bass, Striped Bass, Largemouth Bass, and crappie spp. Possum Kingdom was managed under statewide regulations until September 1, 2002 when the Largemouth Bass minimum length limit was raised to 16 inches and the Striped Bass bag limit was lowered to two per day in response to a golden alga (Prymnesium parvum) fish kill that occurred in early 2001. The Striped Bass bag limit was returned to the statewide bag limit on September 1, 2012. The Largemouth Bass length limit returned to the statewide 14-inch minimum on September 1, 2018. Major golden alga mortality events have occurred in 2001, 2003, 2007, and 2010.

Fish Community

• Prey species: Threadfin Shad were present in the reservoir. Electrofishing catch rate of Gizzard Shad was near the historical average for the reservoir, but most of the Gizzard Shad were too big for most predators to utilize. Electrofishing catch rate of Bluegill was high, with good size structure providing prey for predators and a fishery for anglers.
• Catfishes: The Channel Catfish relative abundance was above the reservoir historical average with many legal length catfish present for anglers. Blue Catfish catch rate was the second highest we have documented with many fish exceeding 20 inches in length. Flathead Catfish have historically been found in the reservoir, but none were caught in the current survey.
• Temperate basses: White Bass and Striped Bass were present in the reservoir. White Bass catch rate was below the reservoir historical average. Striped Bass relative abundance was well above the reservoir historical average and exhibited very good size distribution. Striped Bass body condition was below optimal.
• Black bass: The 2014 Largemouth Bass electrofishing sample was slightly higher than the previous survey in 2012. No Spotted or Smallmouth Bass have been observed since the 2002 survey. There were good numbers of legal-length bass sampled and many just under legal length, which will recruit to legal length within the year based on past growth rates. Few smaller bass were sampled.
• Largemouth Bass: Largemouth Bass electrofishing catch rate was less than the historical average. The relative abundance of legal-length bass has increased though the last few surveys. Part of this can be attributed to the length regulation changing in 2018 from a 16-inch minimum to a 14-inch minimum. Largemouth Bass age at attaining legal length (14 inches) averaged 2.1 years. Largemouth Bass body condition was below optimal.
• Crappie: White and Black Crappie are found in Possum Kingdom Reservoir. Historically, traditional trap netting for crappie resulted in low catch rates caused by the morphology and depth of the reservoir. Furthermore, past creel surveys found little targeted effort for crappie so trap netting was not conducted during the report years. Both species of crappies were sampled during the gill netting survey indicating they were present, somewhat abundant, and of legal length.

Management Strategies

• Monitor the Striped Bass population and stock when necessary.
• Inform the public about the negative impacts of aquatic invasive species.
• Continue sampling Possum Kingdom for zebra mussels which has had positive zebra mussel DNA hits before but have never been observed in the reservoir.
• Conduct additional electrofishing and gill netting surveys in 2020 and 2021 respectively, and general monitoring surveys with electrofishing and gill net surveys in 2022-2023.
• Access and vegetation surveys will be conducted in 2022.
• Perform 9-month creel survey during 2020-2021.
• Continue artificial habitat work when funding becomes available.

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