“Reindeer need a lot of space,” says Issat Turi, 40, an indigenous Sami reindeer herder from Guovdageaidnu, a Norwegian village north of the Arctic Circle. Every winter, Turi and his extended family look after 1,000 reindeer as they graze freely for lichen under the snow on the tundra. In early spring, the family rounds up the animals, loads them into trucks and drives them 300 miles farther north to an island called Reinoya, where the animals birth their calves by the sea.

You need a way to nudge reindeer along. Strategies differ, but for most Sami herders in Norway, the preferred tactic involves snowmobiles and dogs. Use peer pressure too. “Harness the dominant bulls and walk them along,” Turi says. “The others will follow.” Come up with a way to identify your reindeer in case they get mixed up with someone else’s (they will). Turi and other Sami herding families each have a series of small cuts they make in the animals’ ears to tell them apart.

Expect to put in time on the graveyard shift. In late winter, Turi wakes at least once a night to check on his herd. During calving, you’ll need round-the-clock monitoring. Dress in very warm clothing, because you’ll be out in sub­freezing temperatures for hours at a time. Don’t work alone. “It’s always good to be at least two people with the herd,” says Turi, whose family works in shifts of several weeks with the herd, followed by a week or so off for rest.

Watch for predators. Every year, Turi loses animals, mostly calves, to golden and white-­tailed eagles (and a few to lynx and wolverines). In other Arctic countries, you’ll contend with bears and wolves. Beware when crossing frozen rivers. Remember, the world is warmer now. It rains more in winter. Rain that falls on snow can freeze into an impenetrable layer of ice over the lichens and grasses. If the herd faces starvation, scatter food pellets. If you want to herd reindeer, you need to fight to keep big parts of the Arctic undeveloped. As the region thaws, Turi has seen more mining companies, oil-and-gas developers and new roads fanning out over the landscape. “When you lose land to development,” he says, “you never get it back.”