Ornithology: Portrait of a Predator

The more he watched the clumsy, black-and-white wood stork as it fished in the muddy Florida swamp, the more vacationing Zoologist Marvin Philip Kahl Jr. was puzzled. As the big bird slogged awkwardly through the murky, weed-choked water, its long, curved beak dangling half open, it was hardly the picture of a successful predator. Yet it was snagging a fish every couple of seconds. How was it spotting its prey?

Determined to find the answer, Kahl captured a pair of the birds, brought them back to the University of Georgia campus, and studied the problem with the help of Professor L. J. Peacock. One stork was fitted out with segments of a blackened pingpong ball over each eye, and both birds were turned loose in a shallow pool filled with minnows. The blinkered stork sloshed ahead, snapping up fish as quickly as its wide-eyed mate. Vision, the two zoologists explained in the British magazine Nature, has no part in the wood stork's fishing technique. The bird's beak is something like a repeating mouse trap, snapping shut on anything that touches it. If a fish so much as brushes against either of the bird's mandibles, the beak closes in as little as nineteen-thousandths of a second. By contrast, the human eye takes forty-thousandths of a second to blink when startled. This reflex makes the wood stork the fastest fisherman on record, and certainly gives it the fastest jaws in the drawling South.