DNA used to determine the age of lobsters

UK scientists have identified a way of determining the age of a lobster based on its DNA, sharing their results in the journal Evolutionary Applications.

Lobsters are notoriously difficult to age: nobody knows exactly how old they can get, and some experts have estimated they could live on the ocean floor for as long as a century or more. A new DNA-based technique, developed at the University of East Anglia (UEA) in collaboration with the Centre for Environment, Fisheries and Aquaculture Science (CEFAS) and the National Lobster Hatchery, could now be used to help manage lobster fisheries more sustainably.

“It is crucial to be able to estimate how many lobsters of particular ages are present in a given area so that they can be sustainably harvested,” explained UAE’s Dr Eleanor Fairfield, whose PhD research led to the new breakthrough.

The study was led by UAE’s Dr Martin Taylor, who noted, “Until now, a lobster’s age has usually been estimated using its size — but this is inaccurate as individual lobsters grow at different rates.” For example, lobsters with more food or in warmer waters can grow more quickly.

“For a long time, it appeared that there was no accurate way to quantify a lobster’s age,” Dr Taylor said. “Some research suggested that you could tell a lobster’s age by counting the rings in parts of their eyestalks and stomach — a little like counting tree rings. But you can’t do that for a living lobster.”

The research team used a method that relies on quantifying DNA changes that accumulate with age within a lobster. Lobsters raised from eggs by the National Lobster Hatchery, so that the exact ages of individuals was known, allowed the researchers to calibrate their methods.

“We identified a very strong relationship between age and DNA modifications, which allowed us to accurately estimate the ages of individual lobsters,” Dr Taylor said.

“Applying this method to wild lobsters predicted ages that generally aligned with minimum estimates of age based on size.

“Our method shows great promise as a tool for improved management of the European lobster, where information regarding the age structure of stocks is currently missing.”

Dr Carly Daniels, Head of Production Science and Development at the National Lobster Hatchery, concluded, “Having an accurate indication of lobster age will help fisheries, scientists and conservationists alike to understand, manage and conserve our vulnerable lobster stocks, working hand in hand with proactive fisheries management strategies such as stock enhancement.”

Image credit: ©stock.adobe.com/au/Photobeps

Please follow us and share on Twitter and Facebook. You can also subscribe for FREE to our weekly newsletters and bimonthly magazine.