Sampling Bias Associated with Stream Access

Paul E. Balkenbush and William L. Fisher, Oklahoma Cooperative Fish and Wildlife Research Unit, Department of Zoology, Oklahoma State University, Stillwater, Oklahoma 74078

We investigated the effects of sampling site access on estimates of fish abundance in two eastern Oklahoma streams. Fish were sampled with electrofishing at public and remote access sites on Baron Fork Creek in northeastern Oklahoma and Glover River in southeastern Oklahoma. We verified differences in recreational use and habitat between access types in both streams. Recreational use was generally higher at public than remote access areas in each stream. Public areas in Glover River had higher fish densities, were deeper, but had less instream cover than remote areas. However, mean density of centrarchid species, mean depth, and frequency of cover types at public and remote areas in Baron Fork Creek were not significantly different. Although we did not observe a consistent trend between streams in fish abundance at public and remote access sites, our findings indicate that accessibility sampling from public access areas may yield biased estimates of population size. Therefore, we suggest caution when making inferences about populations based on samples taken from these areas.

Copyright © 1999
Texas Chapter of the American Fisheries Society
Last modified: 03/03/04 04:15:38 PM