contributed by Lindsey Goss
Streambank alteration is a measure of livestock trailing, trampling, and shearing that occurs along the streambanks. This method is an annual or short-term indicator of grazing intensity and can be used as a trigger for moving livestock at a predetermined standard level or as an end of season indicator of current year livestock use.
There are several methods for evaluating streambank alteration including modified line intercepts with a sampling frame and step point intercepts measured at specified intervals along fixed-length transects, continuous line intercepts transects, and ocular estimations. The overall goal of these methods is to estimate how much of the streambank has been altered by livestock.
Streambank alteration is very quick and easy method for monitoring annual livestock disturbance to riparian areas. It serves as short-term estimation of the effect of grazing impacts on long-term stream conditions (eg. bank stability and channel morphology) which change slowly over time.
Streambank alteration is not a standalone method for assessing grazing intensity and is generally evaluated in conjunction with additional indicators of livestock use such as residual Residue Measurement - Stubble Height and woody browse utilization. This is not appropriate method to implement on streambanks that are resistant to hoof penetration (e.g. cohesive soil containing clay on dry or entrenched channels) or impervious to disturbance (e.g. bedrock or boulder armored stream channels).
Image source: Burton et al. 2011.
Example of the MIM monitoring frame with five line intercepts projected on the plot. There are four hoofprints on this plot. Lines 2 and 4 each intersect one hoofprint. Line 3 intersects two hoofprints. Three lines intersect hoofprints, so the number of alterations on this plot is recorded as a 3. See the above technical reference for detailed instructions on how to implement this method.
Image source: Burton et al. 2011. Multiple Indicator Monitoring (MIM) of Stream Channels and Streamside Vegetation