Tradinghouse Creek Reservoir - 2004 Survey Report
Prepared by Michael S. Baird and John E. Tibbs
Inland Fisheries Division
District 2-B, Waco, Texas
This is the authors' summary from a 36-page report. For a copy of the complete report, use the download link in the sidebar.
Tradinghouse Creek Reservoir was surveyed in fall 2004 by boat electrofishing, winter 2004 by trap netting, and spring 2005 by gill netting. This report summarizes survey results and contains a management plan for the reservoir based on those findings.
Tradinghouse Creek Reservoir is located in a primarily agricultural area, 15 miles east of Waco in McLennan County, Texas. Average reservoir depth is 19 feet with a maximum depth of 42 feet. The reservoir is eutrophic, with water transparencies typically ranging from 2 to 4 feet. The 2,012-acre reservoir was constructed in 1968 by Texas Utilities Generating Company (TXU) to serve as a cooling-reservoir for electrical power generation. Other water uses include recreation. Constant cooling capacity is maintained in the reservoir by auxiliary water from the Brazos River during low water levels or periods of high water temperature. Fish habitat at the time of sampling consisted mainly of aquatic vegetation (e.g., bulrush Scirpus spp. and cattail Typha spp.) and rock riprap.
There are currently no handicap facilities on the reservoir. Bank access is good and boat access points were renovated extensively in spring 2001. Further information about Tradinghouse Creek Reservoir and its facilities can be obtained by visiting the Texas Parks and Wildlife web site and navigating within the fishing link.
- Prey species: Gizzard shad, bluegill, and longear sunfish made up the majority of the forage collected during 2004 fall electrofishing. Catch per unit of effort (CPUE) for gizzard shad was 183.0 fish/hour, less than one half the 2000 catch rate of 441.0 fish/hour. The index of vulnerability (IOV) (i.e., percentage of individual gizzard shad less than 8 inches total length thought to be vulnerable to largemouth bass predation) was only 17.5, down considerably from the previous three surveys (DiCenzo et. al. 1996). The bluegill CPUE was 176.0 fish/hour, proportional stock density (PSD) was one, and relative stock density for individuals 8 inches and longer (RSD-8) was zero, indicating good numbers of small fish suitable for prey. Catch rates for longear sunfish (57.0 fish/hour), redear sunfish (5.0 fish/hour), and threadfin shad (7.0 fish/hour) suggest minimal contributions to the forage base.
- Catfishes: Channel catfish were the only species of catfish collected during the 2003 and 2005 spring gill netting surveys. Catch rates seem to have stabilized since the 2001 gill netting survey and no longer exhibit an obvious downward trend. Catch rates for the most recent two surveys were 7.0 and 3.0 fish/net night. Relative weights (Wr’s) remained good in 2003 and 2005, respectively averaging 106 and 100 across length classes. Growth rates are also good. According to 2001 length-at-age data, channel catfish reach quality size (16 inches) in two growing seasons and approach preferred size (24 inches) in approximately six years, comparing favorably with other district reservoirs. The last six gill netting surveys have shown a total absence of sub-legal fish. This apparent lack of recruitment was discussed in detail in the 2001 management report, and the following management strategies were recommended for channel catfish: stock advanced fingerlings in 2002 and possibly 2004 at a rate of 10 fish/acre, evaluate the population with annual gill netting surveys to determine stocking success, and collect aging structures from sampled fish to better assess the population. Stocking requests were not met for Tradinghouse Creek in 2002 or 2004 because of limited hatchery production and low stocking priority. Supplemental gill netting in spring 1999 and 2000 was continued in 2003 to investigate the issue of low natural recruitment. The most recent supplemental (spring 2003) and scheduled (spring 2004) surveys also failed to collect a single sub-legal fish. The numbers of fish in the preferred category and greater (16 inches and better) however continue to appear in the samples. What was thought to be a sign of low recruitment in 2001 (i.e., no sub-legal fish in the samples) may be due to rapid growth or gear avoidance by younger year classes. Age and growth data were not collected in 2003 or 2005 due to the low numbers of catfish collected, however efforts should be made in the future to obtain up to date length-at-age data to
determine growth rate.
- White bass: A limited white bass fishery exists at Tradinghouse Creek Reservoir. White bass catch rates have increased considerably since the 2001 survey (e.g., 1.0 fish/net night in 2001, 2.2 fish/net night in 2003, and 9.8 fish/net night in 2005). All white bass collected in 2003 and 2005 were above the current legal length limit (10 inches) and retained excellent body condition with Wr’s ranging from 97 to 112. Values for proportional stock density (PSD) and relative stock density of 10-inch fish and longer (RSD-10) have remained at 100 for the past six surveys. This indicates consistent numbers of fish 10 inches in length and longer, but no fish under 10 inches. This pattern is similar to what we have seen with channel catfish. Young-of-year white bass may not recruit to the collection gear their first few months of life, rapidly approach 12” or more during their first growing season, and appear in gill netting samples the following spring as legal-sized fish. Once again, efforts should be made in the future to obtain up to date
length-at-age data to determine growth rate.
- Black bass: Tradinghouse Creek Reservoir continues to produce some of the highest largemouth bass densities in the district. The 2004 electrofishing catch rate of 289.0 fish/hour is the highest on record for the reservoir and district. The 2003 fall electrofishing catch rate was also very good at 177.0 fish/hour. Fish less than stock size (<8 inches) comprised most of the catch for the 2003 and 2004 surveys, and PSD values were 44 and 68 indicating balanced populations. Largemouth bass 14 inches or longer (RSD-14) were also well represented in the 2003 and 2004 samples (28 and 47 respectively). Fish appeared healthy with Wr’s ranging from 88 to 112, evidence that plenty of forage was available. Growth of all age groups remained good and bass reached the legal size of 14 inches during their second growing season. The percentage of Florida largemouth bass (FLMB) alleles has remained near 72.0% since 1997. Given excellent recruitment, solid growth rates, and steady FLMB influence, quality largemouth bass fishing should persist at Tradinghouse Creek Reservoir for the foreseeable future.
- Crappie: Catch rates spiked in the winter 2000 trap netting survey (1.8 fish/net night for white and 9.8 fish/net night for black crappie), however returned to previous ranges again by 2004 (0.8 fish/net night for white and 0.2 fish/net night for black crappie). PSD (100 for white and 0 for black crappie) and RSD-10 (100 for white and 0 for black crappie) values for 2004 are based on only five individuals and so are inconclusive. Relative weights (Wr’s) were good averaging 102 for the few individuals collected. Both white and black crappie reach the legal size limit (10 inches) by the end of their first year of growth.
- Red drum: Gill netting surveys conducted since 1991 have yielded only 48 red drum to date and have probably underestimated red drum densities. Catch rates for the 2003 and 2005 spring gill netting surveys were 2.8 and 0.6 fish/net night, compared to 0.4 fish/net night in 2001. Relative weights (Wr’s) remain a mystery as there is not currently an index for this species in fresh water. Growth rates are also unknown because otoliths taken from red drum living in power-plant reservoirs are difficult to age accurately and no standard methodology exists for the species. Anecdotal evidence combined with creel data from spring 2000, suggests that fishing is good and that most legal-sized fish caught are in good health. Annual stocking efforts for this species have been very consistent, and good stockings of advanced fingerling (8 to 10-inch) fish from private growers in 2003 and 2004 should provide additional benefits to the fishery over the next few years.
Hydrilla was found in trace amounts during summer 2000, 2001, and 2002 vegetation surveys while none was reported during 2003 and 2004. Although hydrilla appears to be under control and no other noxious species currently exist in the reservoir, annual vegetation surveys should continue.
Based on current information, Tradinghouse Creek Reservoir should continue to be managed with the existing regulations. Although catch rates for certain species are depressed when compared to the 2001 data, condition factors for all species were as good as or better than those calculated in previous surveys. It was postulated that the increase in Hydrilla in the late 1990’s increased the density of available forage species in the reservoir. Conversely, the loss of this vegetative habitat since that time may be responsible for the current low catch rates of forage species – and possibly others like crappie.
Annual gill netting was recommended in the 2001 report to help evaluate potential recruitment problems with channel catfish, and to monitor red drum and white bass populations. Data from this report suggests the channel catfish population has consistent recruitment, and the consistent lack of sub-legal fish in spring gill netting samples has more to do with the temporal component of gill netting, and the possibility of younger fish not being collected by this gear. Non-standard sampling is the only way to determine if these recent views are correct, but none is currently scheduled. No immediate stocking requests are expected for channel catfish in light of this new information.
Crappie stockings will be recommended in the future in an attempt to create a steady, balanced population. Continued annual stocking of red drum is recommended to maintain this popular fishery. Newly adopted stocking and acclimation procedures should be followed to improve post-stocking survival. Research on red drum populations in freshwater power-plants is needed and should include evaluating size-specific post-stocking survival rates and predation rates, determining effective sampling procedures, developing an accurate condition index, and creating accurate aging protocols. The TXU-operated power-plant shifted to a maintenance schedule during winter 2003, and only operates today to perform routine maintenance and system checks. Fractional use of the power plant has resulted in normal reservoir water temperatures throughout the year and without a doubt will have a holistic effect on the fishery. Heated discharge during winter months has enabled the red drum fishery to exist for decades, and without it this fishery is at the mercy of the weather and the severity of future winter temperatures.
Facilities aiding access to the reservoir, including those to be used by physically challenged anglers will be suggested to the McLennan County Commissioner. TXU and other interested agencies should also be contacted and made aware of federal funds (e.g., Boat Ramp Funds) channeled through Texas Parks and Wildlife for such purposes.
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