Late in the afternoon, William F. Gilly, a professor of biology at Stanford University, lugs his equipment across the dirt-topped wharf. A stubble of beard pushes through the sunburn on his cheeks. He is a happy man. Why shouldn't he be? Free of the introspection of the laboratory, he's off to tag the wild Humboldt squid on the Sea of Cortés.
After packing his truck at Stanford's Hopkins Marine Station, in Pacific Grove,California, Gilly drove 900 miles without sleeping to Santa Rosalía, in Baja California, Mexico. Down the long peninsula, where the cacti troop to the indigo sea, past the lava fields and boulders and "pale, burned mountains" that fascinated John Steinbeck. In 1940 the novelist sailed with a marine biology expedition to the Sea of Cortés, or the Gulf of California. It is October 2001, and Gilly is leading a team of seven researchers on an expedition there. He turned 51 on Sept. 11, a birthday well left behind. At Santa Rosalía the heat has slipped below 100 degrees, and the fishy air of the harbor is tickled with marijuana smoke, for the strangers have attracted a small crowd. The Mexicans are curious to see the scientists who, according to the posters they had put up in town, will pay fishermen $50 for each Humboldt squid that is turned in with a yellow tag in its mantle.
Gilly is an electrophysiologist, an expert on the wiring of the nervous system.Ordinarily the test subject for his research is the 8-inch-long squid Loligo opalescens, which seafood lovers know as the market squid. At Hopkins he studies the function of the giant axon, a thick, 5-inch-long nerve fiber that triggers the squid's escape mechanism. The axon sends a signal to the muscle cells of the mantle,where a powerful contraction expels water from the squid's internal siphon, jetting the animal forward or backward. During the last 25years in the lab, Gilly has penetrated ever smaller domains of the squid neuron, into the cell and down to the conductive protein molecules on its membrane, and from there to the genes responsible for producing those proteins. Now, in an abrupt shift of scale that also represents an abrupt career turn, he finds himself launching an uncontrolled experiment in the open ocean on an invertebrate creature that can reach six feet in length and weigh 60 pounds — the Humboldt squid.
The Sea of Cortés is the gash formed when Baja California split away from the Mexican mainland. For a narrow body ofwater it is extremely deep. Within the vertical volume of the sea swarm marlin, sailfish, red snapper, grouper, yellowfin tuna, sweet-tasting mahimahi and groups of Humboldt squid.
The Humboldt, or jumbo flying squid, is one of the largest squid that anyone has seen alive. (So-called giant squid are much larger but are known only from rare, dead specimens.) Fast growing and short-lived, the jumbos move up through the food chain rapidly, so that at two years of age, which is as old as they get, only the biggest fish and the toothed whales can prey on them. But before then most have become meals in the cafeteria of the eastern Pacific. Squid may have become even more important to the food chain in recent years, Gilly notes, since aggressive fisheries have depleted the marine species with backbones. There are indications that squid populations worldwide are increasing, as they move into the niches opened by the harvests of finfish.
