Aquatic invertebrate monitoring at Knife River Indian Villages National Historic Site
Tronstad L. 2013. Aquatic invertebrate monitoring at Knife River Indian Villages National Historic Site. Natural Resource Technical Report. NPS/NGPN/NRTR—2013/778. National Park Service. Fort Collins, Colorado
The Knife River in central North Dakota is not supporting its designated use of recreation in the state because of high concentrations of fecal coliform along much of the river’s length. About 60% of the length of the Knife River has fecal coliform concentrations higher than the recreation standard (200 colony forming units/100 mL). I measured basic water quality, fecal coliform concentrations, Escherichia coli concentrations, and aquatic invertebrate assemblages at three sites to estimate the ecosystem quality along the 5.5 km of the Knife River that flows through Knife River Indian Villages National Historic Site. Basic water quality was similar among sites. The Knife River was basic (pH ~8.4) and daytime dissolved oxygen concentrations were nearly 10 mg/L. Fecal coliform concentrations were at least one order of magnitude above the recreation standard, but E. coli concentrations were below the standard. The Macroinvertebrate Biotic Integrity Multimetric Index of North Dakota scored all sites within Knife River Indian Villages National Historic Site as least disturbed sites. The metric indicated that the Knife River within the park is in good condition compared to other rivers in western North Dakota. Individual metrics rated site #3 as lower quality compared to the other sites. Site #3 had much higher densities of aquatic invertebrates due mostly to Chironomidae (71%). Although the densities of many insect orders were similar among sites, several bioassessment metrics were highly influenced by Chironomidae. Site #3 had the highest benthic organic matter content, which may have been at least partially responsible for the higher density of Chironomidae. Management actions within the park will probably have minimal effects on fecal coliform concentrations. Working with landowners and towns within the watershed to change practices will be essential to reducing fecal coliform concentrations. Further studies are needed to identify the sources of fecal coliform (e.g., human, livestock, or wildlife) in the watershed.
- Type
- Published Report
- Authors
- Tronstad, Lusha
- Date of Issue
- 2013-07
- Publisher
- National Park Service
- Units
- KNRI , NGPN , NRSS
- Keywords
- Aquatic Invertebrate Monitoring, invertebrate inventory
- Subjects
- Ecological Framework: Water | Water Quality | Aquatic Macroinvertebrates and Algae