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Island of the Sharks
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School of hammerheads at Alcyone dive site, Cocos Island. School of hammerheads at Alcyone dive site, Cocos Island.
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"This is Cocos, This is Cool"
by Peter Tyson
October 19, 1998

As we motored Sunday morning—our last day at Cocos Island—toward the hammerhead hangout at Alcyone, I didn't expect to dive. Not with the rain lashing us into lugubriousness and the wind flinging darts of seaspray into our eyes. And the sea being such a bully. Walls of water marching toward Cocos from the west smashed unforgivingly into the panga, making it feel as if we were an accident not waiting to happen but actually happening. Just when you thought you'd gotten into some kind of rhythm with the wave-wracked boat, it went airborne for a long moment . . . . Everyone quickly double-gripped whatever they were gripping and prepared themselves for the landing—thwonk! It might be too rough to launch the IMAX camera.

And conditions below might not be much better. Over the past week or so, divers at Alcyone encountered either lots of hammerheads but poor visibility, or all the visibility in the world but few hammers. And the current at Alcyone is typically "smokin'" (as Mark Thurlow likes to put it). But I had not dove Alcyone in a week, and I wanted a final chance to see the hammerhead schools that make Cocos famous. After three weeks on-site, we were leaving Chatham Bay for the 30-some-hour crossing to mainland Costa Rica.

I didn't expect to dive because I didn't expect Howard Hall to stay down for long. Several times he's called for the camera to be retrieved just minutes into the dive. But he did stay down. Fifteen minutes became a half hour, an hour, longer. I actually fell asleep on the pitching deck. After an hour and a half, the 'com crackled. Billy Holdson took the call, then announced, "I'm going to yell this." He turned to face the other panga, to which ours was tied, and bellowed "IT'S A WRAP!"

A cloud of Jordan's snapper at Alcyone appears unconcerned by a nearby pack
of whitetip reef sharks. A cloud of Jordan's snapper at Alcyone appears unconcerned by a nearby pack of whitetip reef sharks.
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After six expeditions, 287 rolls of film, and 1,656 crew hours underwater, shooting for the large-format film "Island of the Sharks" was officially over. For the first time in 110 days at Cocos, Hall actually said through the 'com, "Don't reload." What's more, he said go ahead and send the scuba divers down. I was delighted to have one more opportunity to dive Alcyone, but given recent conditions, I didn't expect to see much.

I was wrong. Blessedly wrong.

As soon as I reached the seamount eight stories down and took up a position on its crown, I knew it was going to be good. Visibility was 60 to 80 feet, and the current wasn't pushing too hard. Moreover, a school of hammerheads immediately swum into view high above. How could I count them? Thirty, fifty, more? They filled a quadrant of the sky. Spellbound, I craned my neck to ogle this silent parade, the sharks' unmistakable heads standing out against the light like batons held at arm's length.

When they turned and vanished at our bubbles—mine and those of my companions Peter Kragh and Michele Hall—I looked down at eye level for the first time. The parade continued all around me, with other creatures sitting in for the hammers. Barberfish, waiting for a chance to pick parasites off a shark, danced before my eyes. Stern-faced blue-spotted jacks swerved at me, perhaps attracted by my bubbles. Beyond them, out in the water column, four-foot Almaco jacks flashed past, ocean predators nonpareil.


With the grace of a Balinese dancer, a Pacific manta rays glides over our
heads at Alcyone. With the grace of a Balinese dancer, a Pacific manta rays glides over our heads at Alcyone.
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I turned to my left. There above me hovered a thermocumulus of Jordan's snapper, with a pack of whitetips patrolling the mid-water near them. What were these bottom-dwelling sharks doing up there? Out of the corner of my eye I caught sight of Michele pointing at one of the whitetips. No, it was a blacktip, the first I'd seen, and it had a nasty wound behind its right pectoral. I could clearly see the fresh half-moon jaw marks left by what must have been a large shark.

Again I half-saw Michele gesturing and pivoted. A Pacific manta ray was coming straight at me. Kragh was at its side, finning hard and filming with his video camera. This most graceful of rays flapped its enormous pectoral fins in slow motion, a condor of the deep. (Or a Stealth bomber, if you prefer Thurlow's analogy.) Three remoras suction-gripped its expansive flesh. Upon seeing my bubbles, or maybe for reasons all its own, the ray banked left about 20 feet away from me. That's when I descried another hammerhead school high above it. A manta, teeming schools of reef fish, and more hammerheads than you can shake a snorkel at—all in a single glance. How much can a diver take? (In describing the scene later, Michele said "I just thought, 'This is Cocos, this is cool.'")

When the ray and the hammerheads had both faded into the blue, I looked beneath me to make sure I wasn't about to step in a thicket of sea urchins. There, right beneath my belly, lay the open mouth of a moray eel. The animal, its spotted brown body blending in perfectly with the barnacle-stippled coral, lay stretched full-length as if on a coral divan, with a sea cucumber seeming to form a cozy pillow beneath its head. The eel could have sunk its teeth into my navel without straining its neck. But it just lay there, its toothy jaws agape, watching me with eyes like blue marbles.

Author Peter Tyson fins beside a marbled ray. Author Peter Tyson fins beside a marbled ray.
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Checking my air—plenty left, good—I looked up and saw a marbled ray pass me not a yard away. Beyond it, I was surprised to see a pair of hammerheads quite close by—big, heavy-set animals. Like the rest of their kind, they veered away in the presence of my bubbles. Refocusing my eyes, I noticed tiny black-and-gold-striped wrasse spawning an arm's reach away. Like the convict tangs (see Taken by Surprise), they shot straight up and released their spawn before diving back down to the reef. When I glanced up again, the manta ray was sweeping back through. This time, I swam after it, rising in the water column to fin alongside it with Michele for half a minute before returning to my perch on the coral head.

The dive went on like that for three quarters of an hour. Hammerheads in twos or threes somnambulating past the seamount. Blue-spotted jacks prowling for creolefish, with whitetips ready to gobble up the scraps. The manta gliding through three or four times with its wide wings. (Later estimates of its wingspan ranged from eight to 10 feet.) And inches from my navel, that moray, keeping its glassy eyes fixed on me.

Finally, as I rose up the anchor line in the featureless blue, a lone hammerhead swam into view just beneath me, for all the world as if it were saying goodbye. It might well have been. After 150 days in the field, the film crew for "Island of the Sharks" had called it a wrap. We're now on our way back to Puntarenas, which we should reach early this morning, and tomorrow we'll fly back to the States. I can hardly wait to see the IMAX film to relive the memories.

Peter Tyson is Online Producer of NOVA.

Photos/footage: (1,2) Avi Klapfer ©1998 NOVA/WGBH Boston/HHP; (3) Howard Hall ©1998 NOVA/WGBH Boston/HHP; (4) Peter Kragh ©1998 NOVA/WGBH Boston/HHP.

Hammerheads or Bust (Sept. 23)
Get Used To It (Sept. 25)
Nature Reigns at Cocos (Sept. 27)
The PIG and the Process (Sept. 29)
Hammerheads Sighted (Oct. 1)
Assault on Cocos (Oct. 3)
The Director's Cut (Oct. 5)
Swimming with Whitetip Reef Sharks (Oct. 7)
The Magnificent Seven (Oct. 9)
The Search for Lake Cocos (Oct. 11)
Courtship of the Marbled Rays (Oct. 13)
Of Booby and Beebe (Oct. 15)
Taken by Surprise (Oct. 17)
"This is Cocos, This is Cool" (Oct. 19)


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