DV-16-26 Assessing possible mercury contamination in juvenile river herring in the Penobscot Estuary

Karen Wilson
University of Southern Maine

In the Penobscot River Estuary, the return of large numbers of river herring coincides with a legacy of mercury contamination from historic industrial activity. Sea Grant funded research has demonstrated that juvenile river herring are spending much longer in the estuary than previously thought (weeks to months) and consuming estuarine zooplankton during their stay. Although considerable data has been collected on the fauna of the Penobscot Estuary as part of the Penobscot River Mercury Study, little data exist for those species, such as smelt and river herring, that eat zooplankton. This project leverages the ongoing monitoring of the Penobscot River Estuary by NOAA-NMFS scientists to analyze river herring for mercury content. Results from this project will indicate whether or not river herring are accumulating mercury during their time in the Penobscot Estuary, and, importantly, if this presents a significant risk to river herring predators (fish eating birds in particular) in the estuary or in other habitats to which river herring migrate.

Sea Grant funds: $5,000