"Mad Men" actress January Jones continues to speak out on behalf of sharks in a new PSA for Oceana, her second for the organization. She traveled to Belize to swim with a whale shark, the world's largest fish, at nearly 40 feet long. "I wasn't intimidated so much as in complete and utter awe," she says of the experience. "Seeing an animal of that size in the wild is incredible. And then to be able to swim alongside it? It's a feeling that's very hard to put into words. There was a peace that came over me, and a feeling of hope and joy that was intoxicating. I was free diving so I was obviously holding my breath but I didn't want to surface."

Jones wants people to know that "sharks are amazing animals and that most, like whale sharks, are not interested in us. We know this because the science shows it — whale sharks eat plankton. There is no shark that really views us as lunch or dinner. That's why shark attacks and bites are, thankfully, very, very rare. And sharks play a critical role in our oceans as top predators. Without them, things go out of balance. And, now tens of millions of sharks are caught, mostly for their fins, every year. So it's silly to be scared of them. We should be scared for them."

She urges everyone to learn more about sharks at Oceana.org or via books like "The Devil's Teeth" by Susan Casey and become involved in activism for this cause. "You can help push forward legislation and policy that can help save sharks," she says. "It sounds funny, but sharks really need a lot more allies and friends right now."

Photo courtesy Oceana.org

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January Jones swims with sharks to save them
'Mad Men' star January Jones is scared for — not of — sharks, an endangered species. Jones swam with whale sharks in Belize and is an advocate for the organ