urvival in the far north, he spoke of the "edge of the possible." For most of its history, Svalbard has existed beyond that edge. Ancient civilization never got a toehold here. The Vikings didn't colonize it. The Inuit stayed away. Even today, as tourists enjoy daily air service from Oslo, just 2,500 people live here year-round, many working in Svalbard's coal mines. Winter brings perpetual darkness.
But for a select number of species, Svalbard acts as an extraordinary cradle of life. And the secret to the place isn't bound up in the land. Svalbard is ruled by water, light, and temperature.
Up here the biotic machine is fueled by the Gulf Stream, which sweeps up the East Coast of the United States. If you rode the Gulf Stream's main branch, the North Atlantic Current, all the way north, you'd end up in the West Spitsbergen Current off the coast of Svalbard. There the warm, salty current (though at 42°F, "warm" is a relative term) keeps the water mostly ice free and nurtures massive plankton blooms every spring. The plankton lure whales and great schools of capelin and polar cod, which provide food for seabirds and seals. The abundance of seals, in turn, keeps Svalbard's polar bears fed. Adult bears consume a huge amount of seal blubber, primarily from ringed seals and bearded seals. That food produces the energy necessary to keep the bears' massive bodies (males commonly weigh up to 1,300 pounds, females about half that) moving over a home range that can vary from 60 square miles up to 144,000.
The energy-rich waters off the coast also draw an annual infusion of seabirds. Every May and June, when the ice retreats and the tundra clears of snow, upwards of three million birds flock to Svalbard. They're vast in number but not variety. Only about 28 species are considered common or abundant, and only one—the Svalbard rock ptarmigan—has what it takes to survive on land year-round. The birds migrate up here for the safe breeding and the nonstop feasting. A quirk of geology makes the whole thing work. In places, Svalbard's coastline rises from the sea in near-vertical cliffs. They're not sheer walls like Yosemite's El Capitan, though. The cliffs contain millions of rock outcroppings wide enough to support a nest but often too precarious for predators like the arctic fox.
It's a perfect breeding setup. Pairs of fulmars, Brünnich's guillemots, and black-legged kittiwakes, sometimes intermingled on the same cliff, will claim a ledge for the season and raise their chicks on seafood caught just off the balcony, available 24 hours a day in the nightless summer. When the birds take over a cliff, the transformation can be profound. Once, while riding a former fishing trawler around an inner Spitsbergen fjord, I looked up to see a light dusting of snow on a tombstone-gray sea cliff. Glassing the scene with my binoculars, I realized I wasn't seeing snow at all. It was the blending of tens of thousands of kittiwakes nesting on cliff ledges, their white heads creating a pointillist effect from miles away.
As impressive as Svalbard's summer birds are, they're sort of nature's carpetbaggers: here for the good times, gone for the bad. Come September, most will be winging south. It's hard not to reserve your highest respect for Svalbard's year-round residents, each of which seems to employ one of two common strategies to survive the brutal Arctic winter: Keep hunting or cache extra energy.
The master practitioner of the first tactic is the polar bear, of course, which spends much of the winter hanging out around seal breathing holes, waiting for dinner to surface. The arctic fox employs a hybrid strategy. It keeps hunting in white fur camouflage but when times get tough, digs into caches of food lardered months earlier. In more temperate regions the fox's reputation for surplus killing—going postal in the chicken coop, killing far more birds than it can eat—has earned it the enmity of farmers, but up here storing those surplus kills often means the difference between life and death.
For both reindeer and rock ptarmigan, caching extra energy me