Herders select and sort reindeer inside an enclosure in the settlement of Krasnoye in Nenets Autonomous District, Russia. [Photo by Sergei Karpukhin/Agencies]

In Russia's remote Arctic regions, reindeer herding has been a way of life for centuries. Each winter, herders in Russia's sparsely populated Nenets Autonomous District corral their reindeer into open-air pens before selecting weak animals to be culled.

The cull helps preserve the region's fragile tundra by keeping herd sizes down, and local people sell reindeer meat, hide and antlers to make a living.

Igor Ledkov, who works at the Harp agricultural cooperative in the village of Krasnoye, says herders try to maintain the local reindeer population at around 15,000-17,000 animals.

"The size of the cull each year varies, this year we plan to cull more than 3,000 reindeer," Ledkov says.

"We wait until there's enough snow on the ground so the reindeer don't trample the best grazing land when we corral them into the pens."