By Doug Fraser, Cape Cod Times
CHATHAM — For nearly seven hours Tuesday, John King had to read the ocean like the face of a clock. Circling overhead, spotter pilot Wayne Davis called out simple coordinates like "Fish at 1:30, three boat lengths, coming up on shoals."
King, a former Alaskan crab fisherman and captain, and his wife, Pam, have donated their time and vessel this summer to the Atlantic White Shark Conservancy to assist state shark researcher Greg Skomal in tagging great white sharks off the Outer Cape. In two months and 21 trips out to places like Shark Cove, off Chatham's South Beach, King, Davis, Skomal and conservancy volunteers have become a well-oiled machine with 14 new sharks identified and two tagged.
On Tuesday, they added another six great whites and tagged two more with two different kinds of tags: acoustic ones that continuously broadcast a unique identifying signal to receivers on buoys up and down the Outer Cape, and ones that separate from the sharks after a few months and relay data via a satellite.
In response to Davis's commands, King altered course, swinging the pulpit projecting off the bow to the right — about 7½ minutes on a clock face — to the new heading. He nudged the Aleutian Dream forward 60 feet or so, until Skomal shouted "Engine out!" and the vessel drifted up on a 15-foot-long great white shark, its big scythe of a tail swinging to and fro in the green shallows of an offshore shoal with a swagger that had to be respected.
From his perch on the pulpit 10 feet out over the water, Skomal braced himself with his knees on the aluminum rail and readied a long harpoon. This willowy pole ended in a small box the size of half a cigarette pack containing a high-definition underwater camera.
Skomal plunged the pole down next to the massive fish. With long sweeps of the extension pole, he pulled the camera along the side of the shark hoping to capture enough identifying marks such as scars, damage or fraying of the dorsal fin, or unique patterning of the border between the gray upper body and the distinctive bright white undercarriage that gives the shark its name.
After the footage is downloaded and analyzed, each shark is entered into a database, much like the one used by whale scientists to identify and catalog individual right whales and humpbacks. This is the first year of what Skomal hopes will be a five year population study focused on just how many great whites there are in Cape waters, and what the greater population size may be, as well. Conservancy President Cynthia Wigren said her organization was able to raise nearly $50,000 to complete the first year of the study and is working on funding for succeeding years.
But before they use the cameras or tag a shark, researchers want to know if the great white has already been tagged. For each of the seven sharks located Tuesday, Wigren opened a briefcase and pulled out what looked like a small microphone on a cord. She dropped it into the water, and waited for the signal unique to every animal fitted with an acoustic tag.
At one spot, a beeping sound emanated from the briefcase, and a number was displayed along with the name "Chex."
Chex, named for a Texas elementary school student who raised $1,500 for the conservancy, was small, around 10 feet, and pretty chewed up, Skomal said, with a big bite taken out of his caudal fin. He has been known to hang around a buoy marking the eastern end of the channel through the relatively new North Beach inlet.
Skomal theorized that Chex has been keying in on the waterborne scent from the growing seal haul-out area inside the inlet and was likely ambushing them as they swam in and out the channel.
Five miles south of the mainland, South Beach is reduced to a slender isthmus connecting it to the Monomoy Islands. Skomal and King hoped the 15-footer they were chasing would surface enough in the shallower shoaling waters to allow Skomal to tag it.
He loaded a sophisticated cigar-shaped package containing both an acoustic and satellite tag behind the swivel tip of a harpoon.
Soon, the water depth changed from 22 to 10 feet and the big shark changed from a kind of brown blob in the green, plankton-tinged water below to a clearly identifiable shark shape, the dorsal fin just a few feet from breaking the surface, the coloration patterns discernible.
Less than a quarter-mile off the beach, seals stayed in the shallows, as if sensing the danger.
"They are not stupid," said Chilean marine biology student Sebastian Kraft, nodding toward the gray seals.
Skomal placed the tip of the tagging harpoon close to the shark, then pushed down hard, the detachable steel tip anchoring the tags firmly into the base of the dorsal fin. The great white flinched and skittered away, but then continued its leisurely patrol along the beach.
A school of bluefish trailed the beast, hoping it might scare up an easy meal, or that they might participate in the feasting after a kill.
"They are following the bad boys," Skomal laughed.