Examining Hybrid Striped Bass Stocking Rates in Texas Reservoirs: A Trade-off between Abundance and Stocking Efficiency

Abstract

Hybrid striped bass (HSB), which includes palmetto bass (female striped bass Morone saxatilis × male white bass M. chrysops) or its reciprocal sunshine bass (female white bass × male striped bass) support popular fisheries in many Texas reservoirs. Data from 41 reservoirs sampled using gill nets from 1996–2021 (total of 255 reservoir-yr) were used to develop stock-recruit models where fingerling stocking rates were used to predict CPUE of adults in gill nets. Adult relative abundance was described using two size classes based on the statewide 458-mm minimum length limit, catch of fish below (CPUESUB) and above (CPUE458) the limit. A linear mixed-effect model showed stocking rate explained 41–46% of variation in CPUE estimates. Mean stocking rate from 3–4 yr prior to each gill-net sample were best for predicting recruits for the CPUE458 size class, while stocking rate calculations from years 3–5 and 3–6 explained less variation. The cost-effectiveness of the three primary stocking rates (12, 25, and 37 fingerlings ha–1) was evaluated by comparing the stocking costs to the predicted HSB CPUE for each stocking rate. Stockings were less cost-effective at progressively greater stocking rates. Biologists should consider the trade-offs between stocking for increased relative abundance and using hatchery resources efficiently. We recommend stocking HSB fingerlings at 25 fingerlings ha–1 as a general guideline for establishing robust fisheries while maintaining an intermediate level of cost-effectiveness. Stocking at rates higher than 25 fingerlings ha–1 should be reserved for reservoirs where survival of stocked HSB is adequate and documented angler effort is high enough to justify the additional costs.