Atmospheric emissions of mercury in the US are being reduced, but worldwide mercury emissions remain high. Mercury is also being removed from many consumer items. Changes over time in mercury concentrations in fish remain important to resource managers and the general public. There is hope that mercury concentrations in fish will decline, and the number of fish consumption advisories due to mercury will decrease. We compared mercury concentrations in yellow perch (Perca flavescens) from a group of Adirondack lakes with data collected 12-17 years earlier and found variable responses among lakes. We observed an average decline of 14% in yellow perch mercury concentrations over the past 15 years.