Medina Reservoir - 2012 Survey Report

Prepared by Randy Myers and John Dennis
Inland Fisheries Division
District 1-D, San Antonio, Texas

This is the authors' summary from a 22-page report. For a copy of the complete report, use the download link in the sidebar.

Fish populations in Medina Reservoir were surveyed using electrofishing in 2012 and gill netting in 2013. Historical data are presented with the 2012-2013 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

Medina Reservoir (5,410 acres) was constructed in 1913 and is located on the Medina River in Medina and Bandera counties, Texas. It was built for irrigation water supply. Boat angler access is adequate when water level is within 40 feet of conservation pool elevation (CP) with one public boat ramp and two private ramps available. Currently, the reservoir is over 80 feet below CP and about 950 acres in size. Boat access is limited to one private boat ramp and a four-wheel drive vehicle is recommended. Most of the shoreline (75%) is characterized as rock bluff or rocks and gravel. The reservoir contained no aquatic vegetation in 2012.

Management History

Important sport fish include Largemouth Bass, Palmetto Bass, White Bass, and Channel Catfish. All species have been managed under statewide regulations and Florida Largemouth Bass fingerlings were last stocked in 2005. Palmetto Bass were stocked on an irregular basis due to variable availability.

Fish Community

• Prey species: Gizzard Shad and sunfish spp. were the primary prey species. Relative abundance of both has decreased since 2010 which was coincident with the water level decrease.
• Catfishes: Blue Catfish relative abundance and population size structure remained consistent. Channel and Flathead Catfishes were present, but in lower abundance.
• White bass: White Bass relative abundance was low in 2013 and down compared to relative abundance in 2011, likely a result of declining water levels negatively impacting reproduction and recruitment.
• Palmetto bass: Palmetto Bass relative abundance has declined considerably which was most likely caused by lack of stocking and declining water level.
• Largemouth bass: Largemouth Bass relative abundance was substantially decreased in 2012 compared to previous sampling years due to reduced littoral habitat caused by the water level decline.

Management Strategies

• Stock Palmetto and Largemouth Bass if the water level increases to within 40 feet of conservation pool (CP).
• Inform the public about the negative impacts of aquatic invasive species.
• Conduct regularly scheduled gill net and electrofishing surveys in 2016-2017.
• Conduct additional gill net and electrofishing surveys in 2014-2015 if water level increases to within 40 feet of CP.

Performance Report as required by Federal Aid in Sport Fish Restoration Act Texas Federal Aid Project F-221-M-3 Inland Fisheries Division Monitoring and Management Program