Fox River walleye mercury isotope data

Adult walleye were caught in Fox River (Wisconsin) during April 2014. Age-0 walleye were caught in Fox River during October 2014. Total length, weight, age, and proportion of weight represented by water were determined for each of the walleye. Whole-fish homogenates were prepared during 2014-2015 and during 2017. Total mercury (HgT) concentration, methylmercury (MeHg) concentration, and mercury (Hg) isotope ratios were determined in the homogenates during 2014-2015 and during 2017-2018. All mercury determinations were made at the USGS Mercury Research Laboratory in Middleton, Wisconsin.