Environmental relationships to wadeable stream fisheries resources in Mississippi

J.B. Alford¹, D.C. Jackson¹, and M. Beiser².¹Department of Wildlife and Fisheries, Mississippi State University, Mississippi St., MS, 39762, USA, ²Mississippi Department of Environmental Quality, 2380 HWY 80 West, Jackson, MS, USA

Wadeable streams in Mississippi do not garner the attention of most anglers and fisheries managers, yet these systems can provide quality fishing opportunities for centrarchids. The objective of our research was to relate environmental features measured during the National Wadeable Streams Assessment to fish stock characteristics in Mississippi. Multiple linear regression analysis (R²>0.60; P< 0.05) showed that relative abundances (number of fish/angler-hour and percent composition) of largemouth bass (Micropterus salmoides) and longear sunfish (Lepomis megalotis) were significantly related to water chemistry characteristics (alkalinity, ammonia-nitrogen, and turbidity), riparian characteristics (human disturbance and legacy tree size), percent watershed hardwoods, channel characteristics (percent sand and fine substrates and wetted width) and percent invertebrate sprawlers. Mean length at age 1 of these species was related to total phosphorus concentration, riparian shrub and grass density, percent watershed conifers, percent small woody debris inputs, and percent invertebrate burrowers. Moderately disturbed wadeable stream ecosystems supported the greatest abundances and fastest growth rates of young fish (age 0 to 1). Ecosystems with moderately developed watersheds yet unimpacted riparian zones may increase productivity. They allow sufficient runoff levels, elevating alkalinity and phosphorus levels to nutrient poor streams and provide small woody debris for juvenile fish and benthic macroinvertebrate habitat.