Fishes of First-Order Streams in North-Central Mississippi

Abstract

We sampled fishes and measured physical habitat in 14 first-order streams in north-central Mississippi to document fish community characteristics and examine the relationships between the fish communities and physical habitat charac- teristics. We documented 36 species and 11 families from 6943 captures. The five most abundant species were creek chub (Semotilus atromaculatus Mitchell), least brook lamprey (Lampetra aepyptera Abbot), blackspotted topminnow (Fundulus olivaceus Storer), creek chubsucker (Erimyzon oblongus Mitchell), and green sun- fish (Lepomis cyanellus Rafinesque). We also observed that most streams (> 50%) were numerically dominated by: 1) Cyprinidae, 2) fishes having a maximum body size between 300-399 mm TL, 3) insectivores, and 4) guarder-nest spawners. Fish species composition of our study streams was similar to the species composition documented in other medium- and low-gradient headwater streams in the Gulf Coastal Plain. Additionally, fish community structure in first-order streams was significantly correlated with channel cross-section area, woody debris, canopy cover, water depth, velocity, wet width, and substrate types. The observed relationships between fish communities and physical habitat characteristics in first-order stream were similar to fish-habitat relationships observed by previous investigators working in northern Mississippi streams ranging in size from first to fifth-order.