In the broad society of marine fishes, the 300-pound lemon shark pictured on the opposite page ranks somewhere between garbage man and robber baron. The lemon shark has a reputation as a man-eater; this particular shark very likely has prowled often past the succulent white legs of bathing tourists, but the chances are it has bitten none. The lemon, like all the species in the vast order of sharks, has little brains—it is virtually an automaton guided along the path to survival by its keen sense of smell. If it has passed up human legs in favor of a decaying crab, it is merely because dead crab gives the water a richer and more enticing smell.
Several years ago this lemon shark was captured and put in a channel beside the Seaquarium in Miami, where it thrives and offers visitors—as the pictures on the following pages show—a fearsome spectacle of just how hard a shark will work when competing for food against 50 rival sharks. Biologists and skin-divers have come to understand that when competition is heavy, sharks tend to abandon their natural caution. In a mob a new boldness comes over them. The feeding of each shark seems to stimulate all its rivals, and it is the competition, largely, that impels sharks to swallow all manner of things: dead fish and live people and dogs, sofa cushions, bottles, horseshoes and bicycle parts. A single shark, like a goat feeding on a line of wash, has been known to take in all the hooks of a commercial fishline. In an attempt to keep sharks from tuna lines, Ichthyologist Stewart Springer of the Bureau of Commercial Fisheries experimented with small bombs hidden in bait. "If the bomb exploded in the shark's mouth, the smoke would pour through its gills and the shark would take off fast," Springer reports. "But if the bomb merely exploded in its face the shark wasn't bothered. Sharks do not have enough brains to qualify as stupid," Springer concludes. "They are merely automatons, with a good nose, a good appetite and a fine set of teeth."
Tempted by the dangling shape of a dead jack, a 10-foot lemon shark lunges out of the water
Flailing its pectoral fins to gain support for its heavy body, a lemon shark rises almost two feet above the water surface to grab the bait
Sinking back into the water, a shark twists the bait lengthwise to its gullet so that it is easier to swallow
MICHAEL J. FREEMAN