Porpoise Prattle

Ever since they first learned how to eavesdrop, scientists have realized that porpoises are gabby creatures. They whistle, they beep, they squeak--they always seem to have something to say. But no one could be sure whether the whales' small cousins actually talk to each other, or whether they merely use their prattle for underwater navigation--a sort of mammalian sonar. Engineers from the Lockheed Aircraft Corp. have finally decided that they do both.

The Lockheed scientists tuned in on porpoises for a practical purpose: they wanted to study natural noises that might be of importance to antisubmarine warfare. With a string of 15 spar buoys--aluminum tubes weighted at one end so they floated upright with 12 ft. of their length underwater--they blocked the mouth of a Lower California lagoon. The buoys were set soft. apart, making a loose barrier across the channel; on the bottom near by, the scientists spotted two underwater microphones. Their hazard to navigation in place, the scientists retired to their research boat to wait for porpoises to swim through the channel.

Late one afternoon a crewman sighted five Turslops gilli (Pacific bottle-nosed porpoises) 500 yds. away. They moved slowly up the channel, making clicks that were clearly heard through the microphones. Apparently the porpoises located the barrier and did not like it. While still 400 yds. away from it, they moved over into shallow water and gathered in a tight little school. Then one of them separated from the group and cruised along the buoys. When the scout returned, a burst of whistling came through the microphones. Then another porpoise swam out to examine the barrier and returned for a session of whistling. At last the group left shallow water, passed cautiously through the barrier and disappeared up the channel. What the porpoises said to each other, the Lockheed scientists have no way of knowing, but they are satisfied that the underwater travelers first picked out the man-made obstacle with clicking sonar, then talked the situation over with their whistling scouts before proceeding.

This file is automatically generated by a robot program, so reader's discretion is required.