| Research was conducted in the Edmundston reach of the Saint John River in New Brunswick to understand the impacts of sequential sewage and pulp mill effluent discharges on the health of resident aquatic organisms. In the summers of 2005 and 2006, slimy sculpin (Cottus cognatus) and stoneflies (Perlidae) were collected upstream and downstream of these discharges. Exposure to sewage effluents caused increased growth, energy storage, and relative abundance of slimy sculpin, and increased size and development of stoneflies, indicating that fish and invertebrates respond similarly to these discharges. No effects of pulp mill effluents were observed for either organism. This research suggests that both fish and invertebrates with small home ranges can be used to investigate the relative importance of multiple effluents in complex receiving environments. This also suggests that invertebrate populations may be suitable as sentinels in receiving environments where fish may not be usable. |
