Going Deep

Gannets are the bird world’s Olympians, capable of plunging a hundred feet through the air, then slicing through the ocean to chase down fish. 

The wind blows a low glinting light over the white chop of the sea, spouts of water kicking straight up in the air. Hundreds of Northern Gannets, with six-foot wingspans, gather above the frothy ocean before tucking in their wings and dropping from the sky, hitting the water like white arrows. The birds cloud the air, dozens diving each second as if pulled from above toward some invisible vortex on the seafloor. It’s amazing they don’t collide with one another. Once they hit the water they don’t stop; they tunnel below it like a cormorant or loon, chasing down fish. These pursuits can last from five to seven seconds, occasionally more than 10, and take the birds down as far as 70 feet. The gannet’s plunge is almost three dives in one: the dive from the air, the slice into the water, and then the third dive, when they turn submariner.

[gallery:215386|align:left|caption:GALLERY Watch the Gannets dive.] 

Northern Gannets breed only in a few large colonies on rock cliffs, in fewer than 40 places in the world. They range across Quebec, Newfoundland, and the Gulf of St. Lawrence in North America, and from Brittany north to Norway in Europe. Their homes are remote, storm-tossed, and, at times, almost vertical, some nests held to the cliffs only by the bird’s own dung. You could build a poem just from the names of these great craggy rocks on both sides of the Atlantic: Bass Rock, Gullcliff, Bird Rock, Little Skellig, Sula Sgeir, Ailsa Craig. The largest of the single-island colonies, Bass Rock, holds more than 50,000 nests, and while there is something wild and singular about a gannet’s dive, the bird’s life, both in the air and on the ground, is a crowded one. We humans, upon seeing gannets plummet, usually reach for a metaphor and come up with words like “arrows,” “knives,” even “lawn darts.” But the similes are more consistent upon seeing their rocky homes: Almost everyone comes away from the experience saying that it looks as if the rocks were covered with snow. 

To breed among thousands of neighbors is tricky, and violence can break out at any moment, particularly between males, with sword-like bills stabbing. But what may at first look like a great blob of birds is actually ordered by an elaborate system of spacing and ritual, including courteous bows and not-so-courteous bites, and beautiful gestures like “sky-pointing,” when a gannet points its bill upward to indicate its imminent departure to its mate. It turns out that even gannets need their space, and if you measure the distance between nests, you will find exactly two for every 10 square feet.

 

Like many seabirds, northern Gannets are attentive parents, guarding and feeding their single chick for up to 90 days. But when they cut the cord they really cut

the cord. One day the young, which have never flown and have hardly moved from the nest, waddle to cliff ’s edge and take a great plunge into uncertainty. At Bass Rock, they leap off the ledge and glide down to the water more than 100 feet below. According to Bryan Nelson’s classic The Gannet: “Unable to rise from the water because of their excessive weight and still without fully developed wing muscles, they begin a southward migration to middle Atlantic regions.” That is to say, they begin their first migration by swimming south, developing the strength to fly along the way.

 

Northern gannets are the largest member of the Sulidae, a family that includes the Cape Gannet in southern Africa; the Australasian Gannet of New Zealand,

Tasmania, and southern Australia; and, more famously, the boobies, which fill the gannet niche in the warmer waters close to the equator. 

There are of course some threats to gannets. I remember walking through the dunes on Cape Cod after a nor’easter and finding several gannets with broken necks, a surprisingly vulnerable part of the anatomy for a creature that makes its living falling from the sky. It is also worth noting that while oiled pelicans were the media stars of the BP oil spill in the Gulf of Mexico, the first avian fatality was a gannet that had not yet migrated back from its winter home. Imagine diving into a pool of oil.

More depressing, and certainly more peculiar, is the northern Scottish tradition of hunting and eating “guga,” the Scots’ name for gannet chicks. “The chicks are killed with a stick, decapitated, singed in fire, and then pickled—producing a delicacy that has been enjoyed by islanders for hundreds of years,” reports The Independent. There might be a way to twist this into sounding honorable and old-fashioned were it not for a newer tradition: In 2013 the social wing of Scotland’s Ness football club staged its first “world championship” for eating pickled guga. 

But the gannet population is a healthy one, a million birds and growing by most accounts. And while few humans will ever visit a gannet colony, each winter the birds make it easy on us, flying south in great numbers and giving us a chance to witness their aerobatics. It is a show that shouldn’t be missed. When a single gannet dives it is a wildly impressive feat, but when hundreds of them plummet headfirst, one after another, it leaves the watcher breathless. Excitement is too weak a word; giddiness may work better. The birds search the waters from the sky in great symphonic swoops, lifting, pausing, and readjusting before letting gravity do its work, though sometimes supplementing gravity with a couple of power strokes before finally piercing the boiling sea. Though they can descend straight down, they will often follow a particular fish, banking and angling and even corkscrewing through the air. The gannets hit the water with a great thud and send up an impressive splash. Watching them once as they dove, I suddenly saw humpback whales hunting for the same group of fish, and the birds’ splashes and whales’ spouting became almost indistinguishable.

They are the kings of two realms, and if, during the first part of their headlong descent, they look like circus high divers, then during the last they cut through the watery world like heat-seeking torpedoes zeroing in on a target. My field guide calls gannets “gluttons,” able to consume 10 herring or four large mackerel consecutively, which supply their nonstop internal engines. They dive so much because they need more fish, and they need more fish because they dive so much.

 

Gannets are cold-weather birds, and you can see them close to shore on bracing days, days of whitecaps and wind and purple clouds, days when the thought of plunging into water leads to involuntary shivers. But once, on a calmer, warmer day in North Carolina, I had the chance to see a gannet dive from a fish’s point of view. Due to the mild weather, I was able to conduct an ex- periment that I would never have thought possible. I walked to the edge of the water, stripped down to my boxers, and swam out to where the birds were diving.

Numb legs were a small price to pay for a new perspective. I now had a front-row seat, just two dozen feet away. I could feel the gannets hit the water with a great slicing violence. The birds shot into the surf, using gravity and a last thrust of the neck to spear through the surface. Then they disappeared from sight. I knew that gannets could dive from more than 100 feet in the air and reach speeds of 40 miles an hour, but I had never felt those facts like I did that day. I watched the birds plunge and wondered: What does it feel like, that moment of contact and immersion, entering into the dark wetness and immediately giving chase to animals who know only a liquid realm? What skill to both dive with Olympian grace and swim well enough to overtake fish! If I’m honest, it made me a little jealous. Imagine the sheer athletic joy of it. Imagine being equally at ease in both worlds.

This story ran as "Going Deep" in the July-August 2014 issue.