[en] The mark-recapture data collected by Charles County Community College personnel were evaluated relative to population estimation. The data are generally inadequate to achieve reasonable estimates from the methods described by Otis et al. (1978), because too few individuals were captured during the individual trapping sessions due to the low density of small mammals. However, the number of individuals captured during each trapping session can still be used to monitor potential environmental impacts. A field experiment to evaluate the monitoring techniques is suggested