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Data set for a mesocosm to field assessment of the ecological risks associated with neonicotinoids in US streams

December 20, 2021

Neonicotinoids, a widely used class of insecticide, have been found in surface waters globally. They pose a risk to non-target species found in aquatic environments such as aquatic macroinvertebrates. To better understand the effects of the neonicotinoids imidacloprid, clothianidin and their mixtures on aquatic communities we ran a 30 day mesocosm test. Rock trays were colonized with natural benthic communities in the Cache La Poudre River, located in the mountains of Northern Colorado, and relocated to a laboratory experimental stream setting. In total there were 33 experimental streams: 3 controls and 30 treatments consisting of both single compound and binary compound exposures with 5 treatment levels for each exposure series. Water quality and chemistry samples were collected throughout the experiment. Larval invertebrates remaining in each experimental stream at the end of the experiment were collected, enumerated and identified to the lowest taxonomic unit practical, typically genus or species. Emergent insects were collected each day of the experiment and identified to lowest taxonomic unit. Chlorophyll a was measured in each experimental stream 3 times throughout the 30 day experiment.