Physical and Biological Impacts of Gravel Mining on Three Southwest Missouri Streams

In southern Missouri, gravel mining is a small but widespread industry that is based on physically removing gravel from stream channels and flood plains. It is well documented that gravel mining negatively impacts streams in many different ways, including alternations in habitat, flow, and the biological community. For my research I focused on determining possible physical and biological impacts of gravel mining on Bull Creek, Swan Creek, and the Finley River in southwest Missouri. I hypothesized that overall abundances of native game fishes have been significantly altered by local gravel mining operations. Similar studies have indicated that the greatest areas of impact are those stretches of stream that are located within and directly below the actual mining sites. I tested this hypothesis by sampling fish populations in the disturbed and undisturbed reaches and comparing relative abundances of native game fish. I tested impacts on other stream fish assemblages using the Index of Biotic Integrity (IBI). The IBI uses 12 fish community metrics, which I compared among stream reaches. I also compiled total IBI scores for each stream reach sampled. I found higher densities of smallmouth bass (Micropterus dolomieu) at the sites upstream of gravel mines on Bull Creek and Swan creek. In comparing the IBI metrics I found trends indicating that species richness, sensitive species richness, and total numbers of individuals were low within all of the gravel mining sites. Total IBI scores were found to be higher the further away they were located from gravel mining sites. Data suggest that physical habitat variables such as canopy coverage, substrate quality, and depth have been altered by gravel mining