Lake Nacogdoches - 2004 Survey Report
Prepared by Jules Smith and Todd Driscoll
Inland Fisheries Division
District 3-D, Jasper, Texas
This is the authors' summary from a 25-page report. For a copy of the complete report, use the download link in the sidebar.
Lake Nacogdoches was surveyed in 2004-2005 by electrofishing, trap netting, gill netting, a spring access point creel survey, a structural habitat/aquatic vegetation survey, and an angler access survey. This report summarizes results of these surveys and comparisons are made with historical data (1997-2004). Based on this information, a management plan was developed for the reservoir.
Lake Nacogdoches is located on Loco Bayou, a tributary of the Angelina River in the Neches River basin. The City of Nacogdoches is the controlling authority. Primary uses are municipal water supply and recreation. At conservation pool, Lake Nacogdoches is 2,212 surface acres in size, has a shoreline length of 16 miles, and a mean depth of 15 feet. Water level fluctuations average 2 feet annually. Two public boat ramps with loading docks provide excellent boat access. One handicap-accessible fishing pier is also present. Habitat in the lake consists of submerged and emergent aquatic vegetation (mainly hydrilla and American lotus) and standing timber. Most of the land around the reservoir is used for timber production, agriculture, and residential use.
- Prey species: Primary prey species include gizzard shad, threadfin shad, and bluegill. The 2004 gizzard shad catch rate (71.0/hour) is similar to the historical average (65.3/hour), but the majority of fish are not available as prey. Historically, threadfin shad catch rates have been highly variable (mean = 67.0; SD = 125.7) and are probably not reflective of population status. The 2004 bluegill catch rate (502.0/hour) is higher than 2001, 2002, and historical average (382.0/hour, 287.0/hour, and 359.8/hour, respectively). Increased bluegill catch rates coupled with growth and relative weights of adult largemouth bass indicate adequate prey is available. Few anglers target bluegill (3% of total fishing effort).
- Catfishes: Numbers of channel catfish are relatively low in the reservoir (historical average = 0.3/net night). Since 1997, only 5 channel catfish have been collected with gill nets. High densities of largemouth bass and aquatic vegetation probably limit reproduction and recruitment of channel catfish. Few anglers target catfish at Lake Nacogdoches (<1% of total fishing effort).
- Largemouth bass: Largemouth bass harvest has been regulated with a 14 – 21-inch slot limit since 1988. Since the mid-1990s, dense aquatic vegetation coverages (either hydrilla or American lotus) have reduced fall electrofishing efficiency and increased data variability. Since 2001, catch rates have ranged from 68.0/hour (2002) to 147.0/hour (2004). Population size structure has also been variable (PSD range = 53 – 74; RSD 14-21 range = 30 – 56) but reflects adequate recruitment into the slot length limit. Hydrilla and American lotus coverage is typically reduced in spring and lacks dense surface growth, which appears to increase spring sampling efficiency. Largemouth bass spring electrofishing data reflect remarkably similar and high population abundance (CPUE range = 210.0 – 215.0/hour; historical average = 133.2/hour) and size structure (PSD range = 72 – 78). Recruitment of fish into the slot length limit is high (RSD 14-21 range = 42 – 62). Growth of largemouth bass < 15 inches is good, as fish recruit into the slot limit in 2.6 years. Relative weights reflect good fish condition (> 83 for all inch groups and most >90). Electrophoresis revealed the percent of Florida largemouth bass (FLMB) alleles (52.6%) and pure FLMB (7.9%) decreased in 2004. Creel data indicates directed fishing effort towards largemouth bass was 5.5 hours/acre (63% of the total fishing effort) during the spring quarter. Total catch rates (1.0/hour) were high and harvest rates (0.1/hour) were low. Observed harvest was primarily directed below the 14-21 inch slot length limit.
- Crappie: Although populations of both white and black crappie are present at Lake Nacogdoches, trap nets catch few crappies and data is inadequate to assess trends in population abundance. The crappie fishery accounted for 25% of the total fishing effort during the spring quarter (2.2 hours/acre). Creel data suggest that crappie abundance has increased since 2001, as directed effort, catch, and harvest rates all increased. Total estimated harvest of white and black crappie increased 5 and 6-fold, respectively.
Current harvest regulations should remain unchanged. Largemouth bass recruitment into the slot length limit appears high and stable and growth rates of sub-slot fish are good. Relative weights are currently at desirable levels. The largemouth bass population will be monitored closely by conducting biennial spring electrofishing surveys and a spring quarter creel survey every four years. The percentage of pure FLMB in the population is below the goal of 20%. In 2006 and 2007, we will request a FLMB stocking at a rate of 50 fish/acre.
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