Fluke: Or, I Know Why the Winged Whale Sings

as far as they knew. Well, the theory was that they slept with only half of their brain at a time, while the other half took care of not drowning. For an air-breather, sleeping in the water and not drowning is a big problem. (Go ahead, try it. We'll wait.)
    Falling asleep would be so easy with the rebreather, Clay thought. It was very quiet, which was why Clay was using it. Instead of using a tank of air that was exhaled through a regulator into the water as bubbles, the rebreather sent the diver's exhalation back through a scrubber that took out the carbon dioxide, past some sensors and a tank that added some oxygen, then back to the diver to be rebreathed. No bubbles, which made the rebreather perfect for studying whales (and for sneaking up on enemy ships, which is why the navy had developed it in the first place). Humpbacks used bubble blowing as a means of communication, especially the males, who threatened one another with bubble displays. Consequently it was nearly impossible to get close to a whale with scuba gear, especially a static animal like a singer or a breath-holder. By blowing bubbles the diver was babbling away in whalespeak, without the slightest idea of what he was saying. In the past Clay had dropped on breath-holders with scuba gear, only to watch the animals swim off before he got within fifty feet of them. He imagined the whales saying, "Hey, it's the skinny, retarded kid talking nonsense again. Let's get out of here."
    But this season they'd gotten the rebreather, and Clay was getting his first ever decent footage of a breath-holder. As he drifted by the tail, he checked his gauges, looked up to see Amy snorkeling at the surface, silhouetted in a sunbeam, a small tank strapped on her back ready to come to his rescue should something go wrong. The one big drawback to the rebreather (rather than a fairly simple hose on a tank as in a scuba setup) was that it was a very complex machine, and, should it break, there was a good chance it would kill the diver. (Clay's experience had taught him that the one thing you could depend on was that something would break.)
    Around him, except for the whale, was a field of clear blue; below, nothing but blue. Even with great visibility he couldn't see the bottom, some five hundred feet down.
    Just past the tail he was at a hundred feet. The navy had tested the rebreather to more than a thousand feet (and since he could theoretically stay down for sixteen hours if he needed to, decompression wasn't a problem), but Clay was still wary of going too deep. The rebreather wasn't set to mix gases for a deep dive, so there was still the danger of nitrogen narcosis – a sort of intoxication caused by pressurized nitrogen in the bloodstream. Clay had been narced a couple of times, once while under arctic ice filming beluga whales, and if he hadn't been tethered to the opening in the ice with a nylon line, he would have drowned.
    Just a few more feet and he'd be able to sex the breath-holder, something that they hadn't done more than a few times before, and then it was by crossbow and DNA. The question so far was, are breath-holders all male like singers, and if so, does the breath-holding behavior have something to do with the singing behavior? Clay and Quinn had first come together over the question of sexing singers, some seventeen years before, when DNA testing was so rare as to be nearly nonexistent. "Can you get under the tail?" Nate had asked. "Get photos of the genitals?"
    "Kinky," Clay had said. "Sure, I'll give it a try."
    Of course, except for a few occasions when he was able to hold his breath long enough to get under an animal, about a third of the time, Clay had failed at producing whale porn. Now, with this rebreather…
    As he drifted below the tail, so close now that even the wide-angle lens could take in only a third of the flukes, Clay noticed some unusual markings on the tail. He looked up from the display just as the whale began to move, but it was too late. The whale twitched, and the massive tail came down on Clay's head, driving him some twenty feet deeper in an instant. The wash from the flukes tumbled him backward three times before he settled in a slow drift to the bottom, unconscious.
    * * *
    As he watched the pseudo-Hawaiian try to kick down to the singing whale for the eighth time, Nathan Quinn thought, This is a rite of passage. Similar things were done to me when I was a grad student. Didn't Dr. Ryder send me out to get close-up