Factors influencing muskrat (ondatra zibethicus) choice of farm ponds in the Flint Hills.

Abstract

The Habitat suitability Index model was used to assess the habitat and to assess how useful the model is in predicting farm pond use in the Flint Hills of Kansas by muskrats (Ondatra zibethicus). Seven habitat variables were measured to see if they could be used to assess habitat usability including 1) percent shoreline dominated by emergent vegetation, 2) percent of emergent herbaceous vegetation consisting of Olney bulrush (Scirpus olneyi), American bulrush (S. americanus), or cattails (Typha sp.), 3) percent of herbaceous canopy cover within 10m of the water's edge, 4) amount of water supporting SUbmerged or floating aquatic vegetation, 5) number of cattle hoof prints per square meter, 6) year pond was built, and 7) number of mussel shells per square meter. The first four variables were taken directly from the HSI model since they seemed the most applicable to farm ponds. The other three were measured to see if they might be important in assessing muskrat presence in farm ponds. Discriminant function analysis distinguished ponds with muskrats from those without muskrats (Wilks' Lamda of 0.206 significant at p< 0.05). A Mann-Whitney u-test showed that ponds with> 30 % vegetation within 10m of shoreline have muskrats. A frequency diagram plot of landowner surveys indicated that all ponds that lack muskrats were used to water cattle. The mean of estuarine intertidal food/cover was significantly larger for farm ponds with muskrat than without muskrats. In general, my data showed that the HSI was not applicable for use in Flint Hill farm ponds, probably because of a lack of plants and habitat structure on which the HSI is based.