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Quinton Phelps

Publications and source records attributed to Quinton Phelps.

3 recordsLinked to original sources

Life history traits and population dynamics of Freshwater Drum across large river gradients

Objective Monitoring and assessment of nongame native fishes is limited, but conservation interest in these species is growing. Freshwater Drum Aplodinotus grunniens are a wide-ranging species that serve important functional roles and could serve as an indicator for similar but less common species. Our overall objectives were to quantify and compare population dynamic rates and life history of Freshwater Drum among study reaches in the upper Mississippi and Illinois rivers and relate these metrics to hypothesized environmental and anthropogenic factors. Methods We integrated recently collected age data with monitoring data to estimate age and size distributions, growth curves, maturation schedules, mortality rates, and young-to-adult ratios of Freshwater Drum in six study reaches spanning 1,500 km of river. Principal component analyses and linear regression were used to relate environmental and anthropogenic gradients (latitude, commercial harvest, hydrologic dynamics, primary productivity) to life history traits and population dynamic rates. Results We found latitudinal gradients in life history traits and population dynamic rates whereby Freshwater Drum in upstream, higher-latitude study reaches generally exhibited later maturity, slower growth, smaller maximum size, and lower mortality rates compared with those in lower-latitude study reaches. Further, young-to-adult ratios positively corresponded with chlorophyll- a concentration. No clear relationships were apparent between population dynamic rates and hydrologic variation or commercial harvest. Conclusions Latitude is an important structuring component of life history traits and population dynamics of Freshwater Drum in the upper Mississippi and Illinois rivers likely due to both temperature seasonality and disturbance regimes. The presence of demographic structure in a widespread, common species such as Freshwater Drum suggests similar patterns likely exist in other long-lived native fishes.

Illinois, Iowa, Minnesota, Missouri, Wisconsin

Size structure, age, growth, and mortality of flathead catfish in the Robert C. Byrd Pool of the Ohio and Kanawha Rivers

Flathead catfish ( Pylodictis olivaris ) were sampled in the Robert C. Byrd Pool of the Ohio and Kanawha rivers, West Virginia, to inform management decisions based on population characteristics of size structure, age, growth, and mortality. Sampling was conducted with low-frequency boat electrofishing during late May to early June over a four-year period (2017–2020). We examined size structure using proportional size distribution indi- ces. Growth was evaluated using otolith-derived ages, a von Bertalanffy growth curve, and mean length at age data, including comparisons to published mean length at age data of other populations. Annual mortality was estimated with a weighted catch curve. We documented a high-density population (mean CPUE = 49 fish h–1) with low mortality (A = 11.8%), characterized by slow growing individuals with a maximum recorded age of 36. Our results further demonstrate that this population is characterized by a broad size structure that likely is maintained only through low harvest and high rates of catch and release by anglers.

West Virginia

A review of empirical evidence that examines the effectiveness of harvest regulation evaluations in freshwater systems: A systematic, standardized collaborative approach

Harvest regulations are important tools that fisheries professionals use to impact fish abundance, alter population size structure, and improve fishing opportunities. Fisheries professionals often assume that specialized harvest regulations will have specific effects on target fish populations, but these predictions are not always realized because theory and practice do not always match (literature indicates that predictions are not met in about half of the cases). To identify trends that can improve the future success of harvest regulations, we reviewed a representative sample of harvest regulation evaluations for inland sport fish (i.e., 62 evaluations from 41 studies). Our review revealed gaps related to quantitative predictions, evaluation duration, statistical design, researcher–manager collaboration, and data standardization. Fisheries professionals can benefit from shared and thoughtful data collection designs and protocol standardizations. These designs can transform assessment sampling into empirical regulation evaluations that provide generality across locations and time periods with similar effort and cost.

Fisheries Magazine