Scientists hope DNA in water could be way to save rare fish

Scientists in Maine are using DNA to try to preserve the remaining populations of a fish that lives in 14 lakes and ponds in the state and nowhere else in the continental United States.

The scientists are turning their eye to the Arctic charr, which is a species of landlocked fish in Maine that has lived in the state for millennia and is prized by anglers.

The charr face threats such as invasive predators and a warming climate.

They are also notoriously elusive, making them difficult for researchers to track.

Michael Kinnison, a professor of evolutionary applications at University of Maine, and other scientists are working with the state to make sure the fish keep surviving.

Kinnison is working on a project to collect "environmental DNA" from the water bodies where the fish live.

The project involves collecting water samples from the lakes and ponds where the fish are known to live, and studying DNA that they and other organisms shed, Kinnison said.

It'll provide vital information scientists can use to keep charr populations stable, he said.

It's also a much less invasive and time-consuming way than older methods, such as using nets, Kinnison said.

"If your only tool to count a species is a gillnet, and there's not many, do you make the tough choice to risk killing the individuals to find them?" he said.

"It's a way to get an idea of where organisms are located and do it in a way that presents really no harm."