Finally tonight, we go to New England, where a group of seals is making a splash.

On a beach in Westerly, Rhode Island, non-lookers watches 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 the species because prior to the 1970s, the populations were almost completely decimated.

Sarah Callan manages the animal rescue program at Connecticut's Mystic Aquarium.

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

They had become ensnared 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 100,000 marine mammals are killed or injured after becoming ensnared in discarded plastic.

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.

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.

The seals that we released had a variety of tags on them,

and those tags are going to give us really great real-time data about the animal's location, how deep they're diving, and then how long they spend at each depth.

Gray seals can dive up to 1,000 feet for food and can hold their breath underwater for up to 90 minutes.

And Callan says they play a big role in the health of their ecosystems.

Seals help nourish the ocean. They spread nutrients around and they're just such a vital part of the environment.

In addition to marine pollution, habitat loss and climate change threatened 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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