ohn: Finally tonight we go to new England where a group of seals is making a splash.

On a beach in westerly, Rhode Island, onlookers watch as a gray seal emerges from a crate.

And heads toward the waters of the atlantic ocean, flopping along on its belly in an undulating motion known as galumphing.

"It's so important to protect -- Sarah Callan: It's so important to protect this species because prior to the.. populations were almost completely decimated.

John: Sarah Callan manages the animal rescue program at Connecticut's mystic a..

The released seal is one of six her team rescued during March and April from the waters near block island, Rhode Island.

They had become entangled in fishing gear and other debris.

Callan says sea litter - much of it plastic - is a growing threat to seals and other mammals around the globe.

Each year, nearly 100 thousand marine mammals are k.. injured after becoming ensnared in discarded plastic.

Sarah Callan: We've had animals get entangled in frisbees that end up around their neck.

So all sorts of everyday things animals can ingest the plastic as well, which poses many threats to them.

John: Callan's team spent weeks nursing the rescued seals back to health, treating their severe, infected wounds with antibiotics.

Before releasing them, researchers made sure they'd be able to track them.

Sarah Callan: The seals that we released had a variety of tags on them and those tags are gon.. really great real-time data about the animals location, how deep they're diving,and then how long they spend at each step.

John: Gray seal skin dive 1000 feet for food and can hold their breath underwater for up t.. minutes.

And, Callan said, they pla.. big role i.. ecosystems.

Sarah Callan: Seals help nourish the ocean.

They spread nutrients around and they're just such a .. of the environment.

John: In addition to marine pollution, habitat loss and climate change threaten their future and Sarah Callan says her group and others like it will be around as long as seals and other marine animals need help.

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