Gulf of Maine, Explained: Otoliths

As you scroll through your social media feeds, you’ll see all kinds of information — often too much — about your friends. Imagine if the same were true about your fish.

Well, fish aren’t on Facebook, but they do have a public profile of sorts. It’s called an otolith — which you can think of as an inner ear bone. When fish are harvested, scientists can extract otoliths for physical and chemical analysis.

From this tiny calcium carbonate structure, scientists can learn more about how old a fish is, where it was born, and what environments it experienced over its lifetime.

This information is critical to fisheries managers, who need data about fish populations to make good decisions about sustainable harvest.

In this installment of Gulf of Maine, Explained, Fisheries Ecologist Dr. Lisa Kerr explains the importance of otoliths, and how she uses them in her research on Atlantic Bluefin tuna.