Response of Streambanks to Different Intensities and Seasons of Cattle Grazing in Two Montane Riparian Areas in Western New Mexico
Streambank morphology plays an important role in the ecosystem functions of stream and riparian areas. Livestock can potentially have large impacts on streambanks. Understanding the effects of grazing on streambank morphology is important for making good management decisions. Little work has been done to examine the effects of livestock grazing on southwestern stream channels. The purpose of this study was to evaluate the effects of different grazing intensities and different seasons of use on streambank morphology in two montane riparian areas in western New Mexico. No significant largerscale changes to streambanks were detected over the duration of the study. In contrast, many smaller-scale changes were noted to have taken place following cattle grazing. The smallerscale changes observed were not associated with other indicators of streambank alteration such as bank collapse, widening of the active channel, plant community change, or other
larger-scale changes. It was concluded that the smaller-scale changes observed were part of the normal geomorphological adjustments made by streambanks and did not ultimately contribute to lasting streambank morphological change. The resource management and scientific community should be aware that results of streambank morphological studies may depend on which data analysis strategy or response variable is employed.