SREL Reprint #2387

Habitat use and temporal dynamics of blackwater stream fishes in and adjacent to beaver ponds

Joel W. Snodgrass1,2 and Gary K. Meffe3

1Savannah River Ecology Laboratory, University of Georgia, Drawer E, Aiken, SC 29802
2CRESP, Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, NJ 08855-1059
3Department of Wildlife Ecology and Conservation, Newins-Ziegler 303, Box 110430,
University of Florida, Gainesville, FL 32611-0430

Abstract: We sampled stream fishes within and at varying distances from beaver ponds for two years in two southeastern blackwater streams. Our objectives were to determine whether species showed ontogenetic or seasonal shifts in habitat use involving impounded and free-flowing strewn reaches and whether assemblage structure and dynamics varied between ponds and streams and as a function of upstream distance from ponds. Age-0 and adults of most of the more abundant species (15) were collected in either streams or ponds, suggesting no ontogenetic or seasonal shifts in habitat use for these species. The proportions of age-0 to adult fish of four species were higher in ponds than streams, suggesting movement of adults to ponds to breed. The proportion of age-0 to adult Erimyzon oblongus was higher in streams when compared to ponds, suggesting adults of this species supplement food resources by feeding in ponds. Assemblage structure was less stable in ponds when compared to streams. In streams, age-0 and adult fish densities and population coefficients of variation (CV) declined with upstream distance from ponds. Because high CVs were typical of species occurring in streams throughout their fife, and habitat structure and variability were not related to upstream distance from ponds, interactions between pond boundaries and fish movement are probably responsible for the patterns we observed in streams adjacent to ponds.

SREL Reprint #2387

Snodgrass, J.W. and G.K. Meffe. 1999. Habitat use and temporal dynamics of blackwater stream fishes in and adjacent to beaver ponds. Copeia 3:628-639.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).