The Yamal peninsula in the Russian Arctic is home to 15,000 reindeer herders such as Alexei Khudi. Their centuries-old way of life is now under threat because of increased gas drilling in the region. Photos by Florian Stammler, an anthropologist at the Arctic Centre in Finland.

The area boasts the world's biggest reindeer herds, with roughly 600,000 animals managed by 15,000 Nenets nomads. The conical tents, known as 'chums', are home to the reindeer herders and are made of wooden poles and reindeer hide. Whole families sleep inside and there is a wood burning stove in the middle.

Nenets women play an important role in the herders' migration across the region, as they steer reindeer to new pastures. Their work is strenuous, setting up camp in a different place every few days. Here a group of women from the Tazovsky district enjoy a well deserved break at the annual Day of the Reindeer spring festival.

The herders' traditional way of life has lasted for more than 1,000 years. The 21st Century seems a world away at times, but many do have mobile phones, snowmobiles and generators. The herders are against development in the region because they are losing more of the pasture lands which feed the reindeer.

BBC Radio 4's Crossing Continents joined the herders as they begun their summer migration north. Now a new oil field at Bovanenkovo, halfway up the Yamal peninsula threatens the brigade's migration route. Hear the full report at bbc.co.uk/crossingcontinents

The reindeer provide the herders with their transport, clothing, food and their shelter in the Yamal peninsula. The reindeer hide is comfortable and warm to wear and here Nenets women trade on the street in the regional capital of Salekhard.

The Russian birth rate has remained low despite government incentives but the Nenets buck the trend since most families have five or six children. These days most Nenets women prefer to give birth in clinics. Here 17-year-old Kira Khudi looks after her cousin who has just acquired a baby sister.

The Nenets have been good at adapting to a market economy. In the summer herders export velvet antlers, known as 'panty', to China where they are used in traditional medicine.

Nikolai Khudi is the leader of Reindeer Brigade No 4. He says, "we spend our whole life with the reindeer, they're our close friends". It may be a tough existence but many could not imagine living another way. Nina, pictured here, says she likes fresh air and urban apartments are "too stuffy".

Nenets children aged seven to 17 have to spend the autumn and winter months in boarding school for their compulsory education. Nikolai Khudi's grandson will be sent away when he is older. The children return to their parents in early summer by helicopter.

Nikolai Khudi's mother is 81-years-old and has been a nomad all her life and speaks almost no Russian. She says the secret to longevity is eating raw reindeer meat and a white Siberian fish called muksun.

17-year-old Kira Khudi likes helping her mother Nina chop wood, fetch water and prepare food in in the chum - although she says she dreams of going to college in Salekhard and training to be an accountant like her older sister.