Tideline Tours records dolphins

FOLLY BEACH -- Click, whistle, and apparently eavesdrop. That's what dolphins do as they swim by, in case you ever wondered.

Anton DuMars of Tideline Tours takes along a hydrophone so passengers on the tour boat can listen to a bottlenose dolphin call. Four of them swam under the boat recently, and the receiver picked up the usual click click click sound the mammals send out, in order to navigate by the echoes.

The dolphins occasionally whistle simultaneously too, apparently talking to each other.

But on this trip, one of the four broke into a burst of songlike whistling.

"Something else I noticed," DuMars said. "The hydrophone, while underwater, can pick up human voices in the boat. I guess this means that dolphins have the ability to eavesdrop."