Routine monitoring of Lake Champlain fish showed a steady decrease in mercury between the late 1980s and 2011 associated with stricter emission regulations. However, the most recent study, 2016-2017, revealed that mercury has significantly increased in smallmouth bass and yellow perch. Between 2011 and 2016-2017 mercury in smallmouth bass increased by 27% in 14” specimens, while mercury in yellow perch increased by 32% in 7” specimens. Factors known to influence biotic mercury (atmospheric deposition, temperature, primary production and pH) can not account for recent increases, however sediment loading is a likely contributor. Sediment loading to Lake Champlain in 2011 was ~4-fold greater than the average annual load with Hurricane Irene responsible for loading almost an entire year’s worth of sediment in a single day. The increased loading and subsequent rise in fish mercury is reminiscent of the METALLICUS study that showed spiked mercury accounted for ~25% of the mercury in young-of-the-year yellow perch three years after the initial application. Although mercury concentrations have risen in Lake Champlain, the trends did vary by lake segment, the most notable in Malletts Bay where fish mercury continued to decline. Causeways severely restrict water exchange in Malletts Bay and result in seasonal hypoxia/anoxia, both of which may be linked to the continued decrease in fish mercury. Obtaining a better understanding of the factors affecting the mercury cycle in a future with more extreme events will help improve resource management to ensure human and wildlife health.