Scientists at the University of East Anglia (UEA) have found a new, non-lethal way to determine the age of lobsters based on their DNA.

Lobsters are extremely hard to age, with nobody knowing exactly how old they can get.

Marine experts have estimated that they could live on the ocean floor for over a century.

But the new technique, developed in collaboration with the Centre for Environment, Fisheries and Aquaculture Science (CEFAS) and the National Lobster Hatchery, could help the fishing of lobster be more sustainable, as well as providing some insight into how long they live.

The team used a method which relies on quantifying DNA changes that accumulate as a lobster ages.

Lobsters raised from eggs by the National Lobster Hatchery, so that the exact age was known, allowed the researchers to be more certain in their methods.

Dr Martin Taylor, from UEA’s School of Biological Sciences and head of the project, said: “Until now, a lobster's age has usually been estimated using its size - but this is inaccurate as individual lobsters grow at different rates.

"It appeared that there was no accurate way to quantify a lobster’s age. Some research suggested that you could tell a lobsters 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.”

Dr Eleanor Fairfield, whose PhD research led to the breakthrough, said: “Lobsters have hard, inelastic shells and so in order to grow they must shed their old shell and replace it with a new one.

"However, lobsters of the same age don’t always grow and moult at the same time. For example, lobsters with more food or in warmer waters can grow more quickly, which makes it really hard to know how old lobsters actually are.

“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.

“We wanted to develop a new, non-lethal method of determining the age of European lobsters that could be of better use for lobster fisheries management.

"The European lobster was an ideal species to study because it is economically and ecologically very important.”

Dr Carly Daniels, head of production science and development at the National Lobster Hatchery said: “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.”

This research was partially funded by the UKRI Biotechnology and Biological Sciences Research Council and the Seafood Innovation Fund.