Diversion Reservoir - 2004 Survey Report
Prepared by Robert Mauk and Mark Howell
Inland Fisheries Division
District 2-E, Wichita Falls, Texas
This is the authors' summary from a 29-page report. For a copy of the complete report, use the download link in the sidebar.
Diversion was surveyed in 2004-05 using electrofishing, trap netting, and gill netting. The reservoir was surveyed using stratified random sites. The 2004-05 CPUE comparisons made in this summary are compared with the results of Diversion historical averages for the period 1997-2004. A survey of the littoral zone and associated physical habitat types was conducted in 2004 by examining the entire shoreline. A creel survey was conducted from June-November 2002. This report summarizes all survey results and contains a management plan based on the findings.
Diversion is a 3,491-acre reservoir located in Archer (dam) and Baylor counties, and was built in 1924. The reservoir is jointly owned by the City of Wichita Falls and Wichita County Water Improvement District No. 2 and is operated primarily for irrigation purposes. It has also been used as an emergency supplemental water source for the city of Wichita Falls. This municipal use is rare since the water is relatively high in salinity and total dissolved solids (TDS). The Waggoner Ranch based in Vernon, Texas privately owns the land surrounding the reservoir. Vehicle and boat trailer access is through a single tollgate on the northeast side where a $5 daily access fee per vehicle is charged. This is a reduction from the $20 daily access fee per vehicle that had been previously charged until January 1, 2004. Annual permits can be obtained for $200.
Diversion is an impoundment of the Wichita River approximately 20 miles below Kemp Reservoir. Controlled releases from Kemp are used to maintain nearly constant water levels at Diversion. This results in reservoir fluctuations of not more than 2 feet a year. The reservoir has a 234 square mile drainage area, which flows through rolling plains and grasslands. Erosion of Permian outcroppings in the watershed and salt springs result in high concentrations of dissolved salts in the reservoir. Diversion is relatively shallow, with moderately clear water and a basic pH. It has a shoreline length of 28 miles, mean depth of 12 feet, and a maximum depth of 35 feet. Protective cover in littoral areas includes standing timber and over 900 acres of submersed vegetation as observed during the 2004 habitat survey.
Diversion serves as the water supply for the Dundee State Fish Hatchery. On March 16, 2001 a heavy bloom of the toxic golden alga Prymnesium parvum was confirmed in the lower part of the lake. A fish kill occurred at this time but had little impact to the fishery. However, fish hatchery operations were impacted and significant mortalities occurred. During the early months of 2003, 2004, and 2005 the fishery was adversely affected by toxic golden alga blooms and fish kills throughout the reservoir resulting in significant losses of some game fish and a reduction in angling activity.
- Prey species: In 2004, the gizzard shad electrofishing catch rate of 94.0/hr was well above Diversion’s historical average (43.7/hr). The index of vulnerability (IOV) (DiCenzo et al. 1996) was 100 indicating all gizzard shad are vulnerable to largemouth bass predation. The bluegill electrofishing catch rate of 1.0/hr was well below the historical average (64.4/hr), but may not have been indicative of their abundance as evidenced by the trap net catch rate of 103.0/net night sampled a month later. Threadfin shad were sampled during the 2000 electrofishing survey but were not sampled in 2004.
- Catfishes: The 2005 gill netting catch rate for blue catfish was 1.6/net night compared to 2.4 and 3.8 in 2003 and 2001, respectively. The 2005 channel catfish catch rate was 0.7/net night compared to 0.1 and 0.9 in 2003 and 2001 respectively. Both species maintained relative weights near 100. The 2005 survey occurred soon after the golden alga bloom subsided. Most of the fish were sampled near the river indicating that they had not totally redistributed throughout the reservoir. An earlier 2005 gill netting survey, when an active golden alga bloom was occurring resulted in no fish being sampled.
- Temperate basses: The 2005 white bass gill netting catch rate decreased to 1.1/ net night compared to 3.8 and 15.7 in 2003 and 2001, respectively. Part of this decline may be attributed to the timing of sampling after the recent toxic golden alga bloom. White bass were only sampled near the river indicating they were starting to migrate back into the reservoir. While Diversion is not managed directly for striped bass through stocking, these immigrant fish do enter the system from above via Kemp Reservoir. Historically, striped bass have been found in low numbers. Striped bass have not been documented since the 2001 golden alga fish kill.
- Black basses: The 2004 largemouth bass electrofishing catch rate of 10.0/hr represents the lowest catch rate on record for Diversion. It is a significant decrease from the previous 2000 survey catch rate of 82.0/hr. Much of the decrease can be attributed to the 2003 and 2004 golden alga fish kills. Before these two events, largemouth bass were being caught as evidenced by the 2002 creel survey results. The last Florida bass fingerling stocking was in 1993. Spotted bass were not sampled in 2004. Spotted bass were never an abundant species as evidenced by the historical average electrofishing catch rate of 5.4/hr.
- White crappie: The 2004 trap netting catch rate of 0.3/net night was much lower than in 2003 (22.3/net night) and 2000 (1.8/net night). In the 2003 and 2004 surveys, no crappie over 7 inches were sampled. The high 2003 catch rate of small crappie indicates successful reproduction took place after the toxic 2003 golden alga bloom but the 2004 fish kill may have further reduced the abundance of crappie.
- Walleye: Historical evidence from the 1970s, points to limited success of stocking walleye fingerlings to produce a fishery at Diversion. During the 1998-2000 time period, walleye fingerlings became available and were stocked. Walleye were sampled in the 2000 electrofishing and in the 2001 gill netting surveys. Walleye have not been documented since the 2001 golden alga fish kill.
Based on current information, the reservoir should be managed with current regulations. Golden alga blooms should be monitored utilizing Dundee fish hatchery incoming water cell counts as an early indicator of possible problems. Perform additional electrofishing (October 2006), trap netting, (November 2006) and gill netting surveys (March 2007) to monitor fish populations. Request 2005 stockings of largemouth bass and channel catfish fingerlings. Conduct a public meeting in 2005 to inform the public of current status of the fishery and future management plans. Because of the persistent golden alga problems and limited success, the walleye stocking program has been discontinued.
Performance Report as required by Federal Aid in Sport Fish Restoration Act Texas Federal Aid Project F-30-R-30 Statewide Freshwater Fisheries Monitoring and Management Program