MARY LOUISE KELLY, HOST:

A humpback whale has been turning heads in the San Francisco Bay. It is young. It is healthy, but it's also a little early. Normally, humpbacks do not show up in the bay for another month.

AILSA CHANG, HOST:

Allison Payne is a researcher with the Marine Mammal Center, a nonprofit conservation group. She and a co-worker spotted the whale from the Golden Gate Bridge.

ALLISON PAYNE: At first, we really thought it was a gray whale because that's pretty common to see in the bay at this time of year. And so as we rushed down to Cavallo Point to take more photos a little bit closer, we saw the dorsal fin, and it was a humpback. There was no denying it.

KELLY: Now, this particular young whale was not one they had seen before. They knew based on the pattern on the underside of its tail. It's kind of like a fingerprint.

CHANG: Payne says warmer waters may be disrupting food sources for the whales, bringing them closer to shore.

PAYNE: As a one-off, I don't think that it's cause for alarm. But as a general trend, the fact that we are seeing more and more whales using the San Francisco Bay is something that we really want to pay attention to for management.

CHANG: And, she adds, if you see a whale in the bay, give it space. If you're on a boat, slow down. And lastly, if you get a whale of a shot with your camera, email it to the Marine Mammal Center.

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