Dataset for the article "Bioaccumulation of the Pesticide Imidacloprid in Stream Organisms and Sublethal Effects on Salamanders."  Contains imidacloprid and metabolite concentrations for Desmognathus spp., benthic macroinvertebrates, and stream water. Also contains corticosterone concentration data for Desmognathus spp. and body condition indices for 5 species of stream salamander in relation to water imidacloprid concentrations.Dataset for the article "Bioaccumulation of the Pesticide Imidacloprid in Stream Organisms and Sublethal Effects on Salamanders."  Contains imidacloprid and metabolite concentrations for Desmognathus spp., benthic macroinvertebrates, and stream water. Also contains corticosterone concentration data for Desmognathus spp. and body condition indices for 5 species of stream salamander in relation to water imidacloprid concentrations.

We sampled 48 stream sites in Monongahela National Forest (MNF) and two units of the National Park Service (NPS): Gauley River National Recreational Area (GARI) and New River Gorge National River (NERI), in West Virginia, USA. Of these 48 sites, 27 were adjacent to imidacloprid treated hemlock trees and 21 were not.

We collected water samples from all sites. We extracted imidacloprid from stream water and quantified the concentration of imidacloprid in water samples using ultra high-performance liquid chromatography-mass spectrometry (UHPLC-MS). We also quantified the concentration of imidacloprid metabolites from the MNF sites.

We sampled salamanders from all 48 sites. Captured salamanders were weighed to the nearest 0.1 g with a spring scale, and snout-vent length (SVL) and total length were measured to the nearest 0.1 mm with dial calipers. We calculated body condition indices for each salamander.

After sampling salamanders for BCI, we collected adult individuals of the salamander genus Desmognathus to quantify imidacloprid bioaccumulation and corticosterone levels from 11 of the 48 sampled sites. A subset of these salamanders was used to quantify corticosterone, and these salamanders were decapitated in the field and a minimum blood sample of 2 µL was collected within 3 min of initial disturbance of the salamander. Plasma samples were assayed for corticosterone using radioimmunoassay. Salamander imidacloprid concentration was assessed for a subset of salamanders using UHPLC-MS.

Benthic macroinvertebrates were collected from a subset of sites using a D net and imidacloprid concentration within composite invertebrate tissues was quantified with UHPLC-MS.

Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations.