Aquatic Macroinvertebrates in Young Beaver Ponds on a Small Prairie Stream, Wyoming

Abstract

We describe aquatic macroinvertebrates in 10 beaver ponds less than 10 years old on a small prairie stream in southwestern Wyoming. A greater diversity of taxa were obtained from sweep net samples through the water column than from Ekman dredge samples of the bottom substrate. Densities of benthic macroinvertebrates did not differ significantly among the 10 ponds, but the mean density was relatively low compared to values reported for beaver ponds studied in woodland and montane systems. Aquatic macroinvertebrate densities may be low in beaver ponds on prairie streams due to the relatively small amounts of leaf litter that accumulate in ponds and the frequent destruction of ponds by floods.