Bugs as bioindicators: what aquatic macroinvertebrates reveal about ecotoxicology
Rena Ouyang
Mentors: Behrens, Jonathan, Bernhardt, Emily, Ph.D. Department of Biology
Aquatic macroinvertebrates hold high importance in food webs, spending their larval and nymph stages in water before emerging out of the water as adults. Thus, these freshwater organisms can be indicative of water quality and stressors present within their ecosystems. Specifically, the effects of chemical pollution on macroinvertebrates in urban streams begs further research. We hypothesized that as the amount of water pollution decreases, these ecosystems can support higher density, size, and biodiversity. We focused on three sites in Durham, North Carolina over the course of one year: two sites along a creek heavily impacted by development and one reference site in a highly preserved forest. We expected to see variations in macroinvertebrates present with seasonal changes, but we still observed a general trend of biodiversity and size increasing with decreased contamination. The count of organisms yielded more complex results, as more polluted areas in certain months appeared to have higher density. However, when we apply a more holistic and in-depth approach, we consider that this increase in number does not necessarily constitute successful emergence. Therefore, this research suggests that higher water quality encourages more diversity and survival of aquatic macroinvertebrates, and therefore, other organisms in their ecosystems.
