Hawaiians named this mostly submerged atoll for Kamohoali‘i, the brother of Pele and the shark deity of Hawaiian religion, possibly because of the unusually large population of sharks found here. “Maro Reef is murky and spooky,” says chief scientist Randy Kosaki, watching attentively from one of the boats, “so we don’t like to dive on it.”
Nonetheless, Kosaki cannot wait to get into the water, not because he’s overly concerned about his divers dangling like human bait but because he doesn’t want to miss out on the sharks. He dons snorkel gear and slides into the water. He first dives to his colleagues and lightens their load by hauling extraneous gear back to the boat. Then he takes another breath and descends to swim with the sharks.
At 53 the Native Hawaiian marine biologist has been collecting fish—both alive and at the end of a spear—since the 1970s. Like his younger sister, freediver and champion spearfisher Kimi Werner, Kosaki has a natural grace in the water. He’s tall and lean, and when he’s wearing the type of long-blade fins favored by freedivers, Kosaki looks like an undulating, ten-foot-long sea serpent. About a dozen Galapagos sharks trail him, but as soon as Kosaki turns to face them, even the boldest retreat into the gloom. “These were rather timid,” Kosaki says. “Yesterday they were much friskier.”
It’s that kind of crew I find myself among, out here in the Northwestern Hawaiian Islands, hundreds of miles from anyone other than scientific divers, coral reef ecologists and avid spearfishers. The sort of folk who, when someone yells “shark!”, they all jump in the water. But even these self-described fish nerds have their limits. “If I see a white shark, I get out of the water,” says Richard Pyle, one of the deep divers and an ichthyologist at Bishop Museum in Honolulu. “If I see a tiger shark, I get my camera.”
Their enthusiasm is infectious. My own landlubber view shifts from thinking of sharks as toothy gangsters best avoided like hoodlums in a dodgy neighborhood. Instead I begin to appreciate their sleek lines, their power and grace. They seem more curious than conniving. The more time I spend in the water among these sharks and the scientists who love them, the more I, too, want close encounters of the chondrichthyous kind.
Our expedition leaves Pearl Harbor on May 22 aboard the Hi‘ialakai, a research vessel operated by the National Oceanic and Atmospheric Administration (NOAA). Over the next twenty-five days, the ship will explore a vast area of the Northwestern Hawaiian Islands, traveling almost four thousand miles while eighteen researchers and support divers conduct surveys and collect fish, algae and coral—some likely to be species never before seen or identified—over the course of some four hundred dives. By the end of the journey, they will have inscribed oceans of data on waterproof clipboards and recorded thou-sands of underwater images and untold hours of video.
Kosaki’s mission is to explore the deep reefs around the Northwestern Hawaiian Islands—one of the few places left in the world’s vast oceans that remain dominated by sharks, big jacks and other apex predators. The collection of uninhabited atolls, reefs and shoals that comprise the North-western Hawaiian Islands lies far to the west of the main Hawaiian Islands. To both scientists and Native Hawaiians, these are the ancestors of the main islands, formed millions of years earlier by the same volcanic hot spot that is now creating Hawai‘i Island and the yet-to-surface Lō‘ihi seamount to its southeast.
Due to continental drift and other slow geologic forces like subsidence and erosion, these formerly high islands have flattened to emergent reefs and sandy atolls. They are scattered to the northwest of Ni‘ihau like a loose string of jewels set in turquoise lagoons across 1,200 miles of the Pacific. Though small and rarely visited, these islets are places of superlatives: the world’s largest tropical seabird rookery; the last undisturbed refuge for Hawai‘i’s sea turtles and sleepy-eyed Hawaiian monk seals. Its old-growth coral forests are home to the world’s largest known sponge and a black coral that is the world’s oldest known living animal. Among the thousands of species that inhabit these waters is the world’s highest proportion of endemic fish, those species found nowhere else on Earth.
These flyspecks of land and the fifty-mile-wide buffer of protected ocean around them are celebrating their tenth anniversary as a marine national monument. Established on June 15, 2006 as the Northwestern Hawaiian Islands Marine National Monument, it was renamed Papahānaumokuākea Marine National Monument a year later. This summer the monument also celebrates its sixth year as America’s first and still only mixed natural and cultural UNESCO World Heritage Site. At the time of this writing, President Barack Obama is weighing a proposal to expand the monument’s boundary from fifty to two hundred miles out, quadrupling the area set aside for conservation. If that happens, Papahānaumokuākea will become the largest protected area on the planet, either on land or at sea.
Moonlight dances on the waves as Hi‘ialakai crosses the boundary into the monument. The name Papahānaumokuākea comes from Native Hawaiians, who wanted the monument to reflect their understanding that these are the kūpuna islands, the revered elders, both literally and spiritually. The name invokes both the female earth-mother Papahānaumoku and the sky-father Wākea of Hawaiian cosmology, deities whose union birthed the Hawaiian archipelago—and the Hawaiian people.
At 5:32 a.m. the Hi‘ialakai crosses the Tropic of Cancer, the latitude at which the sun reaches its zenith during the summer solstice. The Native Hawaiians who navigated these same waters centuries ago in double-hulled sailing canoes also understood this latitude to be an important boundary, and not just for navigation: It is the line between ao, the world of light and life, and pō, the world of the gods and primordial darkness. We’re headed into pō, a place of so much mana, so much spiritual power, it’s the place from whence all life emerged, beginning with the coral polyp, and to which all life returns after death. This boundary runs through Mokumanamana (Necker Island), an islet with so many archeological sites that it’s thought to be a spiritual and ancestral gateway to the islands beyond, the places of the gods.(Bishop Museum in Honolulu will feature some ki‘i [carved figures] from Mokumanamana in a new exhibit about Papahānaumokuākea beginning August 13 and running through January.)
We enter pō at first light. A soft glow rises in the east as the darkness shades to a palette of pale blues. Water and sky surround the ship, uninterrupted by land. There are no other ships within hundreds of miles, no planes scraping the sky. The only sounds are the low rumble of the engines, the lapping waves and the cries of the red-footed boobies, which had perched on the forward mast for the night.
Lieutenant Faith Knighton stands watch on the bridge of the Hi‘ialakai, which once served as a quiet US Navy surveillance vessel. The only light comes from the computer screens around her, displaying the ship’s position, course, direction and speed with data from satellites, radar, depth sounders and collision avoidance systems. In these quiet early hours, Knighton says she imagines what it would have been like to navigate the vast Pacific without such instruments, using the stars for guidance. “Very few people can name even more than a few stars,” she says. “It’s amazing that Hawaiians could navigate the oceans using stars and get within a few miles of an atoll.” After Knighton visited the Hōkūle‘a, a replica of the kind of double-hulled voyaging canoes on which early explorers discovered and settled Polynesia, she was astonished by its modest size and its low profile in the water. How could those adventurers have possibly navigated close enough to spot land?
As the sun climbs, Knighton beams as she sees one of the signs they must have followed: the bottom of a fluffy cumulus cloud bank is tinted aquamarine, a reflection from an unseen shallow lagoon ahead.
They look more machine than man in their masks, mouthpieces, wraparound hoses, valves, computer displays and tanks. Kosaki and three other divers are suited up, ready to dive to 330 feet—far beyond the limits of traditional scuba gear. Dive safety officer Jason Leonard runs through a thirty-point safety checklist like a drill sergeant. “Attach counterlungs to waist clip!” he barks. “Check!” the divers respond in unison. It’s a serious process, similar to a preflight checklist for test pilots or astronauts. Gear failure at such depths can be fatal. These aquanauts don’t talk about friends they’ve lost on deep dives, though many of them have. It’s all business until the last item on Leonard’s clipboard is checked. Then he lets out a war whoop and sends the four into the deep with “Dive! Dive!”
What compels these men to plumb such depths? “It’s not thrill-seeking,” Pyle says. “It’s the thrill of discovery. The magic moment comes when I see a fish that no one else has ever seen before.” For Pyle, that happens at three hundred feet off of Hōlanikū (Kure Atoll), the westernmost island of the chain and the outer limit of the Hawaiian universe. There, out of the corner of his eye, he spies an unusual Anthias, a multicolored, two-inch-long fish with a distinctive orange spot on its dorsal fin. Though Hawaiian fishes are well documented, the deep-diving team is racking up new species in the limbo of the mesophotic reef, a region they call the twilight zone.
Pyle recorded his capture of the Anthias (a male) on a camera affixed to his rebreather rig. So did Brian Greene, a fish expert associated with Bishop Museum, who captured a female. Unlike with traditional scuba, divers are able to talk into their rebreathers, although the helium that’s mixed with the oxygen and nitrogen makes them sound like biologists from Munch-kinland. Every evening Pyle and Greene sit in the ship’s dry lab and watch their videos, laughing themselves silly as they listen to themselves hunting for rare creatures of the deep in the voices of Alvin and the Chipmunks.
When diving three hundred feet or deeper, bottom time is often limited to fifteen or twenty minutes, followed by a long, slow ascent—often two hours or more—to prevent decompression sickness. It’s tedious, which is why the divers love to see sharks—or mostly love to. At 150 feet, Greene’s camera records a twelve-foot tiger shark beelining for Kosaki from behind. Greene screams into his mouthpiece. At the last moment the shark abruptly turns and disappears.
Kosaki has no clue until he sees the video hours later. “It makes you think about what else you don’t see swimming behind you,” he says. Mostly, he’s disappointed he missed a close sighting. “It’s really amazing to see a tiger shark that big. Their girth is huge,” he says, holding out his arms as if hugging a barrel. “You think of all of the fish, all of the turtles and monk seals that shark ate to get that big.”
Tiger sharks are ambush predators, and stealth is key to their strategy. “I’ve found that when you make eye contact with tiger sharks, they veer away,” says Kosaki. He suspects if he had looked up, the shark would have peeled off sooner. “We’re not on the menu,” he says. Kosaki texts his wife that evening to share the story. She replies with a string of emoji, a hamburger and other edibles. Diving in these wild oceans, her husband is just another morsel in the food chain.
Sharks and other predators tend to dominate healthy coral reefs, scientists say, and help to maintain a balance of fish. And the reefs at this end of the archipelago are among the healthiest in the world. One reason is that they are so remote, far from land-based pollution. Another is that they’re protected from overfishing, which can disrupt a reef’s equilibrium; these reefs have been completely off-limits to fishing for the last decade. Yet even the most remote marine reserve cannot protect against global stressors, including rapidly warming and acidifying waters. Scientists suggest these reefs might be the best positioned in the world to withstand such changes. But are they?
John Burns lays a measuring tape across the reef off Kapou, otherwise known as Lisianski Island, with the help of Keisha Bahr. These newly minted PhD coral ecologists from University of Hawai‘i at Mānoa are evaluating the reef’s health. Burns takes hundreds of pictures from different angles. A computer program will later collate the images to create a 3-D model of this twenty-by-fifty-foot section of reef. This is the third consecutive year that Burns has examined the architecture of this reef; not long ago it was a kaleidoscope of colorful corals, including the gorgeous purple rice coral (Montipora dilatata) that is now designated as endangered on the International Union for Conservation of Nature’s Red List.
In 2014 much of the reef off Kapou bleached after being bathed for weeks in unusually warm water resulting from a global rise in temperature. When stressed, coral polyps eject the symbiotic algae on which they rely for nutrition—and which give the corals their vibrant color. Some-times corals recover from bleaching events, but Burns’ 2015 survey showed that 90 percent hadn’t. In this year’s survey Burns and Bahr are horrified to find the reef smothered by gobs of green algae. The stuff is so aggressive that chunks of it had torn off and collected in sandy channels, like slimy green leaf litter. Burns compares a thriving coral reef to a diverse, bustling city with high-density housing. “A few years ago the complexity of these corals was phenomenal,” he says. “Gorgeous and great habitat. What remains is rubble, a wasteland. It’s hard for me to believe it’s the same place.” Bahr opts for a more direct simile. “It was like diving on a graveyard,” she says.
Deeper reefs held up much better in the surveys. And for the most part the waters here offer an impressive array of fish: great schools of surgeonfishes, clouds of chubs and parades of parrotfishes, some as large as dogs. When it comes to fish, every shallow dive offers a visual feast of kole, or goldring surgeonfishes, blennies, butterfly fishes, tangs, unicorn fishes and wrasses.
The Northwestern Hawaiian Islands have fallen under some sort of protection since President Theodore Roosevelt dispatched the Navy in 1903 to halt the slaughter of albatrosses and other seabirds for feathers to adorn women’s hats. He was the first of five presidents to expand protections. In 2006 President George W. Bush surprised NOAA officials—and the nation—by invoking the Antiquities Act of 1906 to establish Papahānaumokuākea, a monument covering nearly 140,000 square miles. first lady Laura Bush further impressed Island residents in 2007 by (mostly) correctly pronouncing “Papahānaumokuākea” during a speech in Honolulu to announce the monument’s new name.
At that time, George W. Bush could rightly boast that Papahānaumokuākea was the largest marine reserve in the world, edging out Australia’s Great Barrier Reef. Since then, though, larger reserves have been created as part of an effort to meet the United Nations Convention on Biodiversity’s goal to set aside 10 percent of the world’s oceans for conservation by 2020. So far, less than 3 percent of the world’s oceans are protected, compared with 15 percent of its land and inland waters. Many scientists think it’s a good idea to extend those protections to the edge of US juris-diction, the two-hundred-mile Exclusive Economic Zone, to thwart fish poaching, to protect migratory sharks and other fish and to safeguard the seabed—most of which is unexplored—from mining.
Biologist Daniel Wagner coordinates deep-sea research for the monument. On this trip he’s spending evenings using the Hi‘ialakai’s multibeam sonar to map that unexplored seabed. Watching the sonar’s progress on a monitor, Wagner talks about how such surveys have discovered unknown ridges and an undersea mountain that rises 13,800 feet from the seafloor—as tall as Mauna Kea if measured from sea level. It isn’t just fascinating geology down there, Wagner says: Remotely operated vehicles have revealed a rich density and diversity of corals, and they have photo-graphed otherworldly creatures: a ghost-white octopus; a sponge with Shar-Pei-like wrinkles that’s as big as a minivan; a branching coral that stands taller than an adult giraffe; a black coral that’s been carbon-dated to 4,265 years old. Wagner, who studies black corals, has a backlog collection of forty-nine species awaiting further study. All of them, he believes, have never been seen in Hawai‘i or are new to science. “This is one of those rare instances where we are learning about a new environment before damage happens,” he says, but he sees that damage coming. Much of the monument and its surrounding waters overlap with the Pacific Prime Crust Zone, an area rich in manganese, copper and zinc—all elements needed for cell phones and electronics. “We’re running out of land-based sources. Seabed mining is certainly coming,” Wagner says. “If they allow mining here, it will be very, very bad for this fragile environment.”
Before I’m allowed to set foot on Kamole, or Laysan Island, I must change. I put on clothes that have been stored in a freezer for at least forty-eight hours. The hat on my head, the sandals on my feet, the straps on my camera and sunglasses are straight-off-the-shelf new and still a bit frosty. All to make sure no living insects or viable seeds hitch a ride to these remote places. Each atoll I visit means a different set of unused clothes. Such precautions might seem excessive, but there’s a war going on: a battle against aliens—invasive plants, voracious introduced ants and, in the case of Kuaihelani (Midway Atoll), a plague of mice.
Wildlife reigns supreme on all these islands. Millions of seabirds nest on them, beak by jowl. Humans are scarce. Apart from a few dozen people on Kuaihelani and a half-dozen on Hōlanikū, the islands are deserted except during the summer, when small tent camps house a few young volunteers there to monitor monk seals. To walk amid these colonies, surrounded by fluttering wings and a cacophony of cries, is to witness one of nature’s grand spectacles. The Northwestern Hawaiian Islands remain one of the last, best refuges for seabirds, which have seen global numbers plummet by 70 percent since the 1950s.
Because these birds evolved in the absence of humans or land-based predators, they’re vulnerable. Mōlī (Laysan albatross) and ka‘upu (black-footed albatross) lay their eggs on the sand and leave their chicks unguarded for weeks while the adults forage at sea to feed them regurgitated squid, fish eggs and, too often, bits of plastic. Various species of terns, noddies, tropicbirds and shearwaters are also ground nesters. Petrels burrow beneath soft sand. Every step risks tragedy: a crushed egg, an injured chick or petrel family buried alive in a collapsed burrow. Introduced rodents and ants also took a heavy toll on ground-nesting birds until wildlife biologists intervened to mitigate it.
Much of the effort on Hōlanikū and Kuaihelani now focuses on removing Verbesina encelioides, a member of the daisy family that grows faster and taller than the chicks. It engulfs them in a sea of yellow flowers, making it hard for the parents to find and feed them. Many starve. So state and federal wildlife biologists have moved to eradicate this plant and replace it with native bunch grass, Eragrostis variabilis. They are also planting naupaka, Scaevola sericea, a waxy, green-leafed shrub that builds dunes.
Making her rounds on Kuaihelani, Meg Duhr-Schultz, a wildlife biologist with the US Fish & Wildlife Service, checks on a mōlī chick with a red band. It’s the latest offspring of Wisdom, the oldest known wild bird. Wisdom, who is at least 65 years old, has returned to Kuaihelani every year to raise her young since she was first banded in 1956. Whether this chick will have similar breeding success in the decades to come, given rising sea levels, is part of what drives Duhr-Schultz to work on island restoration. After pulling some Verbesina, she stops to admire a fresh dune that appears to be swallowing a naupaka bush; only small branches poke out from the sand. She digs down a couple of inches to reveal new roots reaching out in all directions, securing the aggregated sand. “This isn’t going to stop sea-level rise,” she says, “but it could buy us time over the next hundred years.”
On Kamole, NOAA fisheries has warriors fighting a different battle. Hope Ronco and two colleagues often find themselves focused on another unwelcome visitor: an endless tide of nets, ropes, lines and other discarded fishing gear. “The marine debris is so frustrating,” Ronco says.“It keeps washing ashore.” Ronco walks out on the reef, gathers some line and drags it up the beach, leaving it above the high-tide line. It’s out of the sea at least but not completely out of harm’s way. Monk seals are curious, painfully adept at getting entangled while poking their muzzles into such debris. “A pup could get entangled on land and overheat in the sun. Or it could get entangled in the water and drown,” Ronco says. Kamole has the largest monk seal population in the archipelago, about 250 of a total 1,300 animals worldwide. The crew here intervenes when necessary, and such small-scale rescues are the reason that a third of the seal population is alive today. And after decades of decline, the Hawaiian monk seal population shows signs of stabilizing.
Walking around Kamole seems like a dream, a step back in time. Fat seals lounge on the beaches. Mothers nurse their young. Ronco gives them a wide berth so as not to disturb, but most seem like they couldn’t care less. It’s as if they know: This is their atoll, as it’s been since long before humans came along. They’ve been known to park their blubbery bodies in front of tents and on some islands have even crawled inside to take an afternoon nap.
Nesting seabirds seem equally untroubled. Sometimes, if I get close enough, a mōlī chick rocks back on its knees and claps its beak with a self-defensive bravado that’s more comic than threating. The adult mōlī simply ignore me. It’s unusual and freeing to be a nearly invisible voyeur amid such abundant wildlife. My humanoid form doesn’t even seem to trigger their pattern recognition; maybe they don’t see me as a threat because they don’t really see me at all.
Anywhere I slip into the sea in these waters, I’m reminded that I’m no longer a top predator but rather somewhere in the middle of the food chain. Sharks patrol with hungry curiosity. On every dive at least one huge ulua, or giant trevally, swims straight up to my face, measuring me with its huge, unblinking eyes and thrusting forward its bear-trap jaws as if to tell me who’s boss. And here on these distant atolls, these farthest-flung reaches of the most remote archipelago in the world, it isn’t me. HH