STEVE INSKEEP, HOST:
We have a story of a romance. It's a love affair that heats up in the chilly waters of San Francisco Bay. Here's Chloe Veltman of our member station KQED.
CHLOE VELTMAN, BYLINE: On a cold, gray morning, Roberta Guise and John Rohosky greet each other on the dock outside their swim club.
ROBERTA GUISE: Hey, bruiser.
JOHN ROHOSKY: How you doing, doll?
VELTMAN: The couple, both in their 70s, swims in the bay several times a week. It's played a central role in their relationship for more than 30 years.
GUISE: (Singing) Oh, what a beautiful morning.
VELTMAN: He's sporting a black Speedo, a red swim cap and bright green fins. She's in a black one-piece and canary yellow cap. The conditions on this particular morning aren't exactly beautiful. There's debris all over the shore and shallows and a fast-moving current.
ROHOSKY: Have to go in backwards with fins.
VELTMAN: The water's around 50 degrees. So for safety, Roberta and John have developed this highly distinctive call-and-response system.
ROHOSKY: I'll do the rebel yell. Yahoo (ph).
VELTMAN: John tells me his call puts him in the fighting spirit. Roberta's call is also wild but in a different way.
GUISE: (Imitating seal). I didn't pick the seal sound. It picked me. That's just what came out, and it stuck.
VELTMAN: They're longtime members of the South End Rowing Club, a San Francisco institution dating back to the 1870s. They met at the club in the 1980s and started using their calls soon after they became involved in a clandestine romance.
GUISE: Well, originally we didn't want people to know that we had made it official. So that, I believe, is how we started those calls.
VELTMAN: You mean they were like a secret code?
GUISE: They were like a secret code, yes - originally.
VELTMAN: They'd use the calls to find out if the other one was around at the club.
GUISE: I would call to you to see if you were here. And if I heard something, then I knew you were here and vice versa. So...
VELTMAN: After Roberta and John went public about their relationship, they also put their calls to a different use.
ROHOSKY: When Roberta and I started swimming together more regularly, it was a good way to signal to each other. Yahoo.
GUISE: (Imitating seal). He'll know by how far away the call is where I am in the water, and he'll know to locate me in the water. And ditto with John.
VELTMAN: Roberta recently had a hip replacement, and John has dealt with heart arrhythmia. So their piercing vocalizations can be especially useful in rough conditions. About 15 minutes into their swim, they've been keeping up a steady stroke side by side. But in no time, he's pulled far ahead.
GUISE: John.
VELTMAN: Roberta can't reach John.
GUISE: Hey. Can't hear me, can you?
VELTMAN: Roberta's treading water, trying to figure out which of the several heads bobbing about in the distance belongs to her husband.
GUISE: I can't tell which is you.
VELTMAN: It's time to bring out the seal.
GUISE: (Imitating seal).
VELTMAN: At first, no luck. So she tries again.
GUISE: (Imitating seal).
VELTMAN: Then...
ROHOSKY: Yahoo.
VELTMAN: John swims towards his wife. They embrace and belt out one last call.
ROHOSKY: Yahoo.
GUISE: (Imitating seal).
VELTMAN: For NPR News, I'm Chloe Veltman in San Francisco.
(SOUNDBITE OF IHF'S "AWAKE") Transcript provided by NPR, Copyright NPR.