Aquatic invertebrate monitoring at Agate Fossil Beds National Monument: 2020 data report
Tronstad LM and Tronstad BP. 2023. Aquatic invertebrate monitoring at Agate Fossil Beds National Monument: 2020 data report. Natural Resource Data Series. NPS/AGFO/NRDS—2023/1385. National Park Service. Fort Collins, Colorado. https://doi.org/10.36967/2296671
Monitoring ecosystems is critical to detect trends so that managers can address perturbations. Freshwater streams are connected to the surrounding landscape and their health is a measure of the overall watershed integrity. Streams are the culmination of upland processes and inputs. Degradation and changes within the watershed can be detected in streams using biota living in these ecosystems. Aquatic invertebrates are excellent indicators of ecosystem quality because they are relatively long-lived, sessile, diverse, abundant, easy to collect and their tolerance to perturbations differ. Aquatic invertebrates were monitored at three sites along the Niobrara River at Agate Fossil Beds National Monument in 2020 completing 24 years of data. We identified 48 invertebrate taxa from four phyla (Annelida, Arthropoda, Mollusca, Nematoda) using Hess samplers in the Niobrara River (Appendix A). Insects (65%), Crustacea (28%), Annelida (5%) and Molluska (2%) were the most numerous invertebrate groups in decreasing order of abundance. Of the insects, Diptera (46%) were the most abundant followed by Ephemeroptera (34%), Trichoptera (14.5%), Hemiptera (3%), Coleoptera (2%) and Odonata (<1%). Hess samples collected from the Agate East site had more invertebrates compared to Agate Middle and Agate Springs Ranch sites. Taxa richness, taxa diversity, EPT richness and the proportion of EPT were highest at the Agate East site indicating higher ecosystem quality. Hilsenhoff’s Biotic Integrity was lowest at Agate Springs Ranch, which is the average tolerance value of the invertebrate assemblage. Agate Springs Ranch and Agate East had good water quality, and Agate Middle had fair water quality according to Hilsenhoff (1987).
- Type
- Published Report
- Authors
- Tronstad, Lusha; Tronstad, Bryan
- Date of Issue
- 2023-01
- Publisher
- National Park Service
- DOI
- 10.36967/2296671
- Units
- AGFO , NGPN , NRSS
- Keywords
- aquatic macroinvertebrates, invertebrates, monitor, water
- Subjects
- Ecological Framework: Water | Water Quality | Aquatic Macroinvertebrates and Algae