Updated July 29.
CHATHAM — The water looked like glass as the center-console fishing boat, refitted for chasing sharks, left Ryder’s Cove at 9 am, motored past Chatham Bar through a natural inlet that moves with the shifting tides and entered what those on board call “shark country.”
Greg Skomal made his way out to the pulpit, carefully and quietly walking to the end of the narrow plank that hung out in front of the boat, and peered through polarized sunglasses at a large, lurking shadow below the surface of the water.
Fondly referred to as the modern-day Matt Hooper, who was the iconic marine biologist in “Jaws” played by Richard Dreyfuss, Skomal, who is a Ph.D.-level senior biologist at the Division of Marine Fisheries, raised his arm like he was wielding a harpoon, but he was, in fact, lifting a GoPro attached to essentially a very, very long “selfie stick.”
He was not hunting sharks, but he is part of a team trying to tag them for research. At the helm of the boat was Capt. Josh Higgins, who works in tandem with Skomal and a pilot, who spots dark shadows from the sky to help guide the team.
It only took about 15 minutes from the dock to enter the open ocean on Monday, July 20.
And only another minute or two went by before Wayne Davis, hundreds of feet above the ground in his two-seat, high-wing propeller plane, suddenly appeared and radioed to the boat that he thought he spotted a shark off the beaches of Chatham on Cape Cod. Davis, a Vietnam War veteran and a former fish spotter, said he saw a dark shadow against the whitewashed sand, near the south end of North Beach Island. Davis’ plane holds a belly tank, Higgins said, and he could spend up to 12 hours in the sky, eyes always peeled for sharks.
Monday was the fourth tagging excursion for the nonprofit Atlantic White Shark Conservancy (AWSC) team this summer, and as Higgins navigated toward the shadow, the boat passed several receivers that run parallel to the coast to pick up on tagged sharks. The receivers are placed out in the open ocean by the conservancy, and sense tags placed on the animals by the team. The goal of the conservancy, in part, is to study white sharks, which are now a protected species. For generations, they were hunted as trophy fish for anglers, and despite conservation efforts, their official stock status remains uncertain. To this day, not much is known about their behavior — even how or when they reproduce.
The shadow that Skomal eyed from the pulpit, at Davis’s direction, didn’t move much, and he realized that what Davis spotted really was just a shadow, an optical illusion created by the sun, waves, and whatever manner of sealife lay beneath the water. Skomal’s used to that, though; his book about great white sharks is literally called “Chasing Shadows.”
Less than 10 minutes later, though, Davis, who could see through about 25 feet of water, radioed again. This time, through clock-bearing directions (“1:30 westbound”) and some “3 boats ahead,” Davis brought the boat right next to a 10.5-foot dark mass that moved.
Upon initial inspection, he appeared as a dark, unassuming shadow against the ocean bottom. But as he gradually came up to the surface, and bits of churned-up life forms, sand, and dirt started to clear, that mass became a great white shark named Pearl — whose width was almost more impressive than his length.
Pearl was first identified in 2019 and tagged by Skomal and the conservancy at the end of September in 2022; since then, through an array of acoustic receivers located from Monomoy Point to Provincetown, he’s been detected over 7,000 times, according to the conservancy’s “Sharktivity” app and White Shark logbook. Because Pearl was already tagged, Skomal only used the GoPro to get some underwater footage.
Pearl was first identified in 2019, and tagged by Skomal and the conservancy at the end of September 2022; since then, through an array of acoustic receivers located from Monomoy Point to Provincetown, he’s been detected more than 7,000 times, according to the conservancy’s Sharktivity app and White Shark logbook. Because Pearl was already tagged, Skomal only used the GoPro to get some underwater footage.
“Animals in general, fish in general … they’re creatures of habit, and it really boils down to how successful they are in feeding in an area,” Skomal said about Pearl, who’s migrated back to the Cape seemingly year after year. Some individuals are transient, he added, and don’t stay long, probably because they don’t successfully feed, so the habitat isn’t “energetically beneficial.”
The team saw four other sharks besides Pearl that day — three white sharks, another of which was already tagged, and a basking shark. It was a good day in terms of sightings, Skomal said. In previous years, they’ve had some very slow Julys.
Sharks typically “overwinter” much farther offshore or down South, and come up to Massachusetts waters as temperatures warm, much like fish, and move back down or out in early November. Skomal said they typically trickle in, and noted a “very credible report” of a shark-bitten seal that washed up on Lucy Vincent Beach in Chilmark in May. Still, the bulk of the white shark population, especially the larger ones, doesn’t come through until July or August.
Skomal said there’s a chance, however, that some of the white sharks now bypass Cape Cod and move straight up to the Gulf of Maine or Canada. “We’re going to look at this,” he said. There are data that demonstrate that sharks move up to Canadian waters more and more, and he wants to know the reason — water temperature, climate change, or restoration of natural prey to the area.
Since 2009, Skomal has tagged 400 individual sharks, though probably only 250 tags are still active; others either died or were eventually shed by the animal. Skomal uses a tag technique developed in the early 1960s by Jack Casey, a pioneer in shark research, and places a small intramuscular dart at the base of the shark’s dorsal fin. Casey started the Cooperative Shark Tagging Program, a collaborative effort between fishermen and NOAA Fisheries, which has tagged more than 300,000 sharks across more than 50 species since the 1960s. The tags can tell Skomal when the shark is going up or down, left or right, as well as speeding up and slowing down.
On Monday, he tagged a shark that was about 300 yards off the beach in 12 feet of water. It was a 10-footer that was logged as MA2602. All tagged sharks, with photos and demographics, are added to the app and logbook, and from then on, live detections are marked across a map of the Cape as the acoustic tags emit high-frequency sounds that are picked up by the receivers. Skomal also takes a post-tag video to check on his deployment of the sensor. The team alerts beach managers, each of whom has their own set of protocols, whenever they spot a shark close to shore as well.
As the boat glided alongside Pearl and another tagged white shark, an 11-foot male named Baobab, whom Davis found because he followed the shark’s algae track (a trail that follows a shark after he swims through an algae or seaweed bloom), Dr. Lauren Brewster, assistant professor of fisheries oceanography for School for Marine Science and Technology at UMass Dartmouth, let out the cord of a hydrophone that broadcast the tag’s sound back to the boat. Patrick Rex, a research scientist for the conservancy, was then able to identify the white shark by the tag’s frequency.
Skomal and the conservancy have five live receivers, marked yellow and with solar panels, along the east side of the Cape, as well as 70 other tall spar buoy acoustic receivers that are placed from Rhode Island to New Hampshire. The data on the nonlive receivers are collected when they’re hauled for maintenance at the beginning of every year.
There were receivers on either side of the Vineyard by Skomal, who used to live on the Island and studied sharks there for more than two decades, in some of the earlier years of his research, but they never indicated that there was a residency of sharks, those that stay for a few months, near the area. It wasn’t until the 2000s that white sharks were seen in New England or in Island waters; a 13-foot female was found trapped in a small pond on Naushon Island in 2004.
“We really haven’t been able to start intensively studying white sharks in the Atlantic until they became predictably present off Cape Cod,” Skomal said; seals, which represent sharks’ preferred prey, made a comeback after a near extinction. Previously, scientists relied only on dead specimens that were brought in by fishermen; now, they can track their movements through tag technology.
Sharks use the waters off the Island as a highway, Skomal said. “There’s no real number of seals to concentrate white sharks long.” Even near Nomans Land, where Skomal said he’s heard there are a lot of seals, his old receiver didn’t pick up many detections, which was a surprise to him.
Recently, a 13-foot, 9-inch shark called Contender was in the news as the largest male white shark tagged in the Atlantic. But Skomal has tagged larger ones. James, first tagged in 2014, is a 14-foot male. Meanwhile, Skomal said he’s tagged 16- and 18-foot females.
And Luke, a 13-foot white shark, was tagged June 24, 2016. Skomal said he named him in honor of Luke Gurney, who died that year fishing in his boat No Regrets off Nantucket. The shark’s been detected more than 30,000 times, one of the highest number of detections, Skomal said. Skomal also participated in the ninth annual Fluke For Luke tournament this month.
Skomal works for the state, which pays his salary, but the conservancy, co-founded by Cynthia and Ben Wigren in 2013, funds the at times costly expenses of his research. Skomal needs to either hire a boat and plane, or at the very least pay for the fuel, to study sharks in the wild.
And despite deep interest from experts, like Casey before him, white sharks remain incredibly elusive, even for Skomal.
White sharks are large pelagic animals, which live in the water column of the open ocean, that travel great distances across the ocean. “It’s incredibly challenging to get an understanding of their basic biology,” Skomal said. “That’s why many shark species have lagged behind other species” in terms of human knowledge of them.
Skomal’s interested in fine-scale behavior of sharks: What do they do — not just day to day, but hour to hour, minute to minute, and second to second? What drives their behavior? How does that relate to their age and life stage? Also, how do they reproduce? “Nobody on Earth can tell you where that happens,” Skomal said.
The white sharks are very solitary, lone wolves, but at some point, they have to mate. “That’s my fascination,” Skomal said.
“The more time I spend with these animals, the better understanding I’m getting of them,” he said, even just their behavior around the boat when he goes out to tag them. When one white shark saw Skomal’s GoPro, he or she turned toward the boat and then shot away. Skomal called that one “squirrelly,” and he wasn’t able to tag the animal.
“The bottom line is we don’t know a heck of a lot. Although we’ve studied them hard, there’s so much we still need to know,” Skomal said.
Editor’s note: This story was edited for print. This is the print edition.
