On the afternoon of Sept. 25, 2002, a group of marine biologists vacationing on Isla San José, in Baja California Sur, Mexico, came upon a couple of whales stranded along the beach. A quick assessment indicated that they had died quite recently. The scientists radioed a passing vessel and sent a message to a colleague at a nearby marine-mammal laboratory, who came to the beach to do an examination.
They were beaked whales, of which there are 20 known species. Relatively small members of the cetacean family, they resemble outsize dolphins, and because of their deep-diving ways, they are among the least observed and understood. Curiously, the stranding on Isla San José followed by just one day the stranding of at least 14 other beaked whales 5,700 miles away along the Canary Islands beaches of Lanzarote and Fuerteventura. Rescuers there worked feverishly to water down the whales and keep them cool. They all eventually died, however, and some of their bodies were immediately sent to the nearby city Las Palmas de Gran Canaria for analysis.
It is nearly impossible to pinpoint the precise cause of a whale’s stranding. Theories invariably include factors like the straying of a sick and dying whale leader, faithfully followed by the members of his pod, or sudden shallows along the shores of a migratory route. The two strandings in September 2002, however, did have something intriguing in common. It was noted by the Canary Islands rescuers that naval vessels were carrying out exercises that day not far offshore, a situation that had accompanied four other mass whale strandings on Canary Islands beaches since 1985. And while no such military exercises were being conducted off the beaches of Isla San José, the vessel that the scientists radioed turned out to be a research ship dragging an array of powerful underwater air guns that were repeatedly set off the previous morning in the course of seismic tests of the region’s ocean floor.