Impacts of human development on habitat and fish communities in Douglas Lake.

Abstract

As human populations continue to increase exponentially, there is an ever-increasing stress put upon our fragile ecological communities. While there has long been a focus on anthropogenic effects on terrestrial systems, research on how shoreline development affects adjacent aquatic systems has not been so extensive. This study looks for significant changes in biotic and abiotic factors between similar habitats along developed and undeveloped shoreline in Douglas Lake. At each of the four sites, habitat variables (macrophyte densities, temperature, pH, dissolved oxygen, total nitrogen and phosphorus, and turbidity) were measured and fish metrics (fish abundance, species richness, species diversity) were estimated using multiple capturing methods. We found that fish species richness increased in developed areas while total species abundance was highest in undeveloped marsh habitat. We also found higher submergent macrophyte densities in our developed sites. However, most of our tested variables were similar between developed and undeveloped sites--indications that the incremental residential modifications along the western side of Douglas Lake have yet to significantly alter the lake's aquatic systems.