War of the Whales by Joshua Horwitz Read Free Book Online

biosonar. By bouncing sound clicks off their prey’s hard shell, day or night, beaked whales easily outcompeted the other predators in the canyon who could only hunt by daylight. Their ability to hunt squid at increasing depth drove the beaked whales’ ascent to the top of the canyon’s food chain.
    When the hard-shelled nautiloids evolved to abandon their shells to avoid biosonar detection, beaked whales refined their biosonar to echolocate the
internal
structures of the soft-bodied squid—which then developed survival countermeasures including camouflage, shape-shifting, and ink-cloud diversions. Millennium by millennium, the beaked whales improved their sonar to defeat these escape mechanisms and chase the squid deeper into the canyon. This evolutionary pursuit-and-escape minuet between squid and beaked whales continued for thousands of generations, until the whales could hunt squid at depths of a mile or more—deeper than any other predator. 2
    To hunt at such extreme depths, beaked whales made several physical and metabolic adaptations, allowing them to dive quickly with a minimum of drag, to tolerate the cold temperatures and crushing hydrostatic pressure at depth, and most importantly, to regulate their breathing to enable deep foraging dives that could last an hour or longer. Other deep-diving cetaceans, such as sperm whales in pursuit of giant squid, have made similar adaptations. But none dive as deep, and surface as briefly, as the beaked whales of the Great Bahama Canyon.
    Beaked whales routinely dive deeper than 5,000 feet and remain underwater for more than an hour; the deepest dive ever recorded by an air-breathing mammal was a Cuvier’s beaked whale that descended 9,816 feet in a dive that lasted 137 minutes. 3 Humans can dive only to a few hundred feet without risking decompression sickness, or “the bends.” 4 By comparison, a WWII German U-boat reached its crush depth at 860 to 920 feet. Even the deepest-diving of modern military submarines can’t dive as deep as a beaked whale. 5
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    The plane flew due north over dozens of tiny cays offshore of Abaco, many of them unnamed and uninhabited patches of sand and scrub barely poking out of the water. From the co-pilot seat, Balcomb scanned each of the cay’s shoreline through binoculars. For the first hour aloft, he didn’t spot anything.
    Just then, as they flew over Water Cay, off the southern bight of Abaco, Balcomb spotted something on the beach. He motioned to Anspach, who took the plane into a steep circle dive and made a low pass over the island. Balcomb videotaped the dark spindle-shaped carcass lying at an angle in the sand, while Anspach noted its GPS position.
    As they were taking a second low pass over the beach, a call came in from Claridge over the plane’s VHF radio. She’ d found a Blainville’s behind Cross Harbor. “The sharks must have chased it into the lagoon yesterday,” she said, her voice crackling. “It probably stranded when the tide went out this morning. I can still see the grooves in the sand where it tried to work itself free.” Despite the static, Balcomb could hear her excitement at finding such a well-preserved specimen. “I’ d say it’s only been dead a few hours. Couldn’t be fresher.”
    Five minutes later, they flew over the lagoon, and Balcomb could see Claridge, Ellifrit, and several Earthlings hovered over the whale’s body. Anspach set the plane down nearby and Balcomb hustled over to join them.
    Just as Claridge had reported, the whale was newly dead. No bad smell or decomposition. Tissue was fresh and firm to the touch. And the carcass was in pristine condition. Not a shark bite on it.
    He wanted to get the whale up on dry land where he could take the head and necropsy the organs. The head would tell them if there was damage to the ears and brain, but he hoped that the other organs might also hold clues to what had driven the whale ashore.
    The tide was just starting to come