Impacts of hydraulic fracturing development on macroinvertebrate biodiversity and gill morphology of net-spinning caddisfly (Hydropsychidae,Diplectrona)in northwestern Pennsylvania, USA

Hydraulic fracturing (fracking) poses significant threats to freshwater resources and stream ecosystems. Little research exists to quantify the ecological impact and in Pennsylvania alone over 10,000 wells have been permitted. This study aimed to determine if hydraulic fracturing is having any impacts on stream ecosystem health by measuring stream pH and temperature, macroinvertebrate index of biological integrity (IBI), and the gill morphology of individuals in the Hydropsychidae Diplectrona taxa. Six streams in northwestern Pennsylvania were selected as study sites (three with fracking occurring in their watershed and three without fracking). IBI scores were significantly higher at non-fracked sites and were also correlated with stream pH. Macroinvertebrate gill width did not vary between fracked and non-fracked sites but was correlated with percent hydric soils, suggesting that hydric soils may be a good long-term indicator of stream dissolved oxygen. While our results did not indicate differences in H...