Colin Thackray

How polluted your tuna is depends on where it comes from

By Colin Thackray, Nereus Fellow at Harvard University

It’s fairly common knowledge that tuna is high in methylmercury, a neurotoxin that bioaccumulates in marine food webs. This means that methylmercury magnifies further up the food web – tuna eat smaller fish that eat even smaller fish or plankton — all of which could contain the contaminant.

Measuring mercury levels in the ocean: A scientist at sea on the Research Vessel Endeavor

By Colin Thackray, Nereus Fellow at Harvard University

The oceans are very expansive. Their enormous size and distance from where people stay long term presents a challenge for scientists monitoring the oceans. Unlike many atmospheric measurements for meteorology which we can make just outside of cities, often at airports, to get good measurements for ocean science, a journey on the sea is often required. Around the world, there are many ships designed or outfitted specifically for bringing scientists to the ocean – so called Research Vessels (RVs).