Mercury Stable Isotope Assessment of Dragonflies and Fish Tissues across United States National Parks

This dataset details mercury (Hg) stable isotope values in dragonflies and fish tissues collected across U.S. National Parks. Dragonfly samples were collected as part of the Dragonfly Mercury Project (https://geonarrative.usgs.gov/dmp/), a citizen science project focused on using dragonfly larvae as biosentinels for Hg bioaccumulation. Fish were collected as part of separate park-wide monitoring initiatives. Biological samples were collected from 2014-2019 and composited for Hg stable isotopes measurements by the U.S. Geological Survey Contaminant Ecology Research Laboratory (CERL, Corvallis, Oregon). Measurements for Hg isotopes were performed by the U.S. Geological Survey Mercury Research Laboratory (MRL, Madison, Wisconsin).