Kate Barrett, who recently joined the St. Joseph River Basin Commission as an Aquatic Ecologist, successfully secured a grant from the Indiana Academy of Sciences. The funding helped the Commission launch a new long-term water monitoring program that aims to establish baseline information on the health of several tributaries of the St. Joseph River. This new program will help answer that burning question, “How is the river doing?”
The program expands on the existing aquatic monitoring efforts for the St. Joseph and Elkhart Rivers conducted by the cities of South Bend, Elkhart and Goshen. The Commission is monitoring 12 sites in small streams in predominantly agricultural landscapes on both the Indiana and Michigan sides of the basin, including Turkey Creek, Mill Creek, and the Prairie and Fawn Rivers. These sites will compliment the existing work being done in the urbanized portion of the basin.
The Commission is monitoring these sites by sampling benthic macroinvertebrates, organisms without a backbone such as snails and aquatic insects, that tend to live on bottom surfaces such as rocks, sand, and other substrates. They are the cornerstone of aquatic food webs because they are a prime food source for many fish species and they play a major role in nutrient cycling.
These small critters are also valuable for scientific research and watershed management because the composition and diversity of their communities can serve as a proxy for stream health. Some species are extremely sensitive to different stressors that can impact streams, including sedimentation, nutrient loading, and low dissolved oxygen levels, while others are more tolerant of degraded conditions. In addition to looking at the types of species present, the Commission will be analyzing the elemental composition of macroinvertebrates to get a better understanding of the types of resources that are supporting these cornerstone communities.
The Commission is busy deploying passive in-stream samplers that benthic macroinvertebrates will colonize over the course of the summer. Then, Commission staff will retrieve these samplers and ship them to the Midwest Biodiversity Institute, where all the critters will be identified. Commission staff will collect additional samples from the sites to analyze macroinvertebrate elemental composition. By analyzing the species diversity and resources supporting benthic macroinvertebrate communities, the Commission hopes to understand how local land cover and watershed activities can impact stream health. By understanding the linkages between the land and stream health, the Commission can work with stakeholders to protect and maintain the existing health and functioning of our basin’s water resources.