Evaluating aquatic macroinvertebrates as bioindicators of freshwater habitat quality in the Sacramento Mountains in New Mexico

Global change, including pollution and climate change, has increased stresses on freshwater resources and, in many cases, reduced the ability of these freshwater systems to host a variety of organisms. The macroinvertebrate assemblages of freshwater systems may reflect ecosystem quality, due in part to their limited dispersal ability. In this study, we used macroinvertebrates in conjunction with algal communities and water chemistry as bio-indicators of quality of river and associated wetland habitats in the Sacramento Mountains of New Mexico, which is largely forested with some low-level development and cattle grazing. River sites were generally shallow and dominated by rocky substrates, while wetland habitats were often associated with headwater springs. Preliminary sampling results suggest the stream has no major signs of disturbance as all the sites sampled had at least 50% EPT taxa present; mayflies (Ephemeroptera) were found to be dominant at all sites. High levels of Nitrates were found in areas of low-level agricultural development. Species richness decreased with excessive levels of nitrates. Phosphorus levels were examined and suggest it is a limiting nutrient in algal growth, which may indirectly affect food availability for macroinvertebrate assemblages. One of the U. S. Forest Service’s objectives is to track conditions and human activities over time in order to effectively manage the Nation’s forests. Our physical and biological assessment of the streams and wetlands in the Lincoln National Forest will provide a platform for future research and for developing guidelines for land management, conservation, and restoration efforts.