Delta Lake - 2004 Survey Report

Prepared by John Findeisen and Aaron Walters
Inland Fisheries Division
District 1-E, Mathis, Texas

This is the authors' summary from a 10-page report. For a copy of the complete report, use the download link in the sidebar.

Delta Lake was not surveyed during the 2004-2005 sampling year due to low water level conditions. This report summarizes the reasons for the low water level and contains a management plan for rebuilding the fisheries within the reservoir.

Reservoir Description

Delta Lake is a 2,261-acre reservoir located in Hidalgo County, 2.5 miles north of Monte Alto. The reservoir is divided into a public section (approximately 1,500 acres, east side) and a private section (approximately 761 acres, west side). The two sections of the reservoir are divided by State Highway 88 and are only connected via a pipeline. The reservoir is used for water supply, irrigation and recreation. The lake is very shallow and turbid. Substrate is composed primarily of small rock, clay, sand and silt. Littoral habitat consists of periodically flooded terrestrial vegetation, large stands of bulrush and cattail, and standing timber. During summer 2004, the Delta Lake Irrigation District began draining the reservoir to begin a bank stabilization project and construct a canal on the east side of the reservoir for the purposes of moving water through the reservoir for irrigation needs during drought years. Both projects should to be completed in March 2006. Conservation pool for Delta Lake is 50 ft MSL, however, the reservoir’s elevation fell below 44ft MSL during the initial stages of the bank stabilization and canal construction projects. During the sampling season, the public section of the reservoir was drawn down to approximately 300 acre-feet of water.

Fish Community

The current population status of prey species, channel catfish, white bass, largemouth bass, and white crappie is unknown.

Management Strategies

• Continue to manage the reservoir with existing fish harvest regulations once the two projects are completed and the reservoir refills.
• Conduct non-standard (outside standard time periods) electrofishing, trap net, and gill net surveys to assess remaining fish populations after the reservoir refills. Stock bluegill, redear sunfish, threadfin shad, and imperial strain channel catfish after the completion of the two projects and the reservoir refills, if determined necessary by the non-standard surveys. Stock Florida largemouth bass for two consecutive years and white crappie (management stocking, adults) for one year following the stocking of prey species and channel catfish, if determined necessary by the non-standard surveys.
• Conduct additional electrofishing, trap net, and gill net surveys the fall following the stocking of largemouth bass and white crappie. Conduct standard electrofishing, trap net, and gill net surveys two years after the additional surveys.
• Work with the Delta Lake Irrigation District on introducing native aquatic vegetation into Delta Lake to enhance juvenile fish habitat.
• Continue to encourage the Delta Lake Irrigation District to apply for a Texas Parks and Wildlife Department boat ramp grant.

Performance Report as required by Federal Aid in Sport Fish Restoration Act Texas Federal Aid Project F-30-R-29 Statewide Freshwater Fisheries Monitoring and Management Program