r nature reserves. A remarkable thing happens when you give animals habitat and peace. They thrive. Svalbard's walrus population, winnowed to a few hundred animals by the 1950s, rebounded to more than 2,600 in 2006. Only a thousand reindeer grazed in the valleys in the 1920s. Today some experts believe there may be as many as 10,000.
The days of outright slaughter are gone, but humans continue to pressure wildlife here in indirect ways. Toxins like PCBs and perfluorinated compounds swirl up to Svalbard on air and ocean currents and become trapped in the fatty tissue of glaucous gulls, great skuas, arctic foxes, and ringed seals, compromising their immune systems. Polar bears carry much higher levels of the pollutants than their Alaskan and Canadian counterparts. Climate change, meanwhile, forces a retreat of the summer ice pack, imperiling the region's polar bears. The wildlife that thrives up here has adapted to one of the toughest habitats on Earth. As temperatures rise, those birds, fish, and mammals will be forced to adapt even further.
Perhaps there is cause for hope in the curious ways Svalbard's wildlife has already adjusted to humans, the predator turned protector. In the coal-mining outpost of Barentsburg, dozens of black-legged kittiwakes have turned abandoned buildings into makeshift bird cliffs, nesting on the window ledges. At midnight or noon—it makes no difference to the birds—the parents leap off the ledges to dive after fish schooling in the harbor below. In their own small way the kittiwakes are expanding the edge of the possible, windowsill by windowsill. It's ingenious but, for Svalbard, not atypical. Up here opportunity and abundance often appear in unlikely places.