Observations of the distributions of five fish species in a small Appalachian stream
The notion has been growing that resident stream fishes exhibit a greater capacity for movement than was previously thought. In this study, we recorded the distributions of four resident fish species (longnose dace Rhinichthys cataractae , blacknose dace R. atratulus , mottled sculpin Cottus bairdi , and rainbow trout Oncorhynchus mykiss ) and one nonresident species (central stoneroller Campostoma anomalum ) in Rock Creek, a small tributary of Cosby Creek in Great Smoky Mountains National Park, over the period 1979-1995. During this study, 1,998 individuals of resident species were collected from stream sections considered to be within a common area of distribution for each species. Forty-five individuals of resident and nonresident species were captured upstream of these areas, and eight of these fish were considered to be larger than individuals considered typical for each species. Small mammal dispersal theory concepts were used to classify and describe fish movements outside of common areas of distribution. These movements were identified as important in maintaining population connectivity within stream drainages, contributing to reducing the potential for local extinctions of populations and to the recolonization of unoccupied habitats. This study highlights the need for continued study of fish movements in stream drainages and for development of appropriate resource management strategies based partly on the spatial dynamics of fish populations and communities.