This dataset provides chironomid counts for the Holocene sediment sequence retrieved from Crooked Pond (United States). Sediment cores were retrieved from the lake using a 1-m long handheld piston corer deployed from a floating coring platform during field work in May 2009. Volumetric samples were obtained from splits of the core and processed in the laboratory (University of New Brunswick, Canada) using standard protocols. Chironomid counts are presented against both depth (cm) and age (cal yr. BP). A total of 58 downcore 1-cm-thick samples were analysed, ranging between 477.5cm depth (9056 cal yr BP) and 0.5cm depth (the present). The chironomid record provides information about changes in the chironomid fauna as well as in within-lake conditions. The dataset was produced to inform on the exact age and duration of a major lake-level lowstand during the mid-Holocene. This lowstand was compared to palynological transitions determined on pollen samples from an older core sequence derived from the same coring location.

Ceratopogonidea head capsules and Chaeborus mandibles are included in line with other publications from the Nearctic region.