Mercury Bioaccumulation in Food Webs

We know from our past research that mercury concentrations can be high in many organisms in Nova Scotia (e.g. rusty blackbird, bats, loons, fish). However, much less is known about methylmercury accumulation in invertebrates. Our recent projects have examined methylmercury in dragonflies, polychaetae worms, and many other invertebrates. We collaborate on food web research all over the planet including Patagonia, Portugal, the Arctic, and across North America.

Mercury Speciation and Photo-Reactions

One of my primary research questions has been "Why are some remote ecosystems more sensitive to mercury accumulation?" We examine the role of solar radiation in determining if mercury is retained in an ecosystem and whether it will accumulate in organisms. We are currently examining these processes at both contaminated sites and in freshwater lakes, coastal estuaries, and soils.

Mercury Interactions with Dissolved Organic Matter

Dissolved organic matter is a key variable controlling many processes in natural waters. Using both lab and field experiments we aim to characterize organic matter in natural waters and its interactions with mercury. The relationship between ultra violet radiation absorbance and dissolved organic matter is key in natural waters. Ultra violet radiation can instigate a variety of chemical reactions that affect mercury binding with organic matter, photo reactivity, and bioavailability.