Image by Tanpa Dhakal via Nepali Times, used with permission.

This story was originally published by Tanka Dhakal at the Nepali Times. An edited version is republished below as part of a content-sharing agreement.

Yaks, which used to be the mainstay of the culture of Himalayan communities in Nepal, have been in steady decline because of lifestyle changes, human outmigration, inbreeding, and the impact of the climate crisis.

The National Agricultural Census shows that the total number of yaks in Nepal went down from 53,000 to 48,000 over the past three years. There are now fewer than 10,000 households across the mountains rearing yaks for a living.

Yaks are the generic name for the long-haired, bison-like oxen that live at 4,000–5,000 metres (approximately 13,000–16,000 feet) in the Himalayan mountain range and the Tibetan plateau.

The country's Ministry of Agriculture and Livestock Development runs a Yak Genetic Resource Centre in Syangboche at 3,885 m (12,746 ft). Established in 1973, the centre is supposed to ensure that the yak population of the Khumbu region remains robust, gives adequate milk, and maintains a healthy variation in its genotype.

The centre keeps 155 yaks for research, but a lack of budget and competing priorities mean that it has not been able to fulfil its true potential in meeting the challenges this domesticated cattle species faces.

“All we are doing is protecting the yaks we have; we do not have the resources to conduct genetic studies,” admits technical officer Ramlallan Yadav, who has been stationed at the centre for the past 24 years.

Yak in Langtang Valley where the milk is used to produce Emmental cheese. Image by Kunda Dixit/Nepali Times, used with permission.

The high-altitude cattle are all lumped together, but there are specific types. Nak are female domesticated yak. Chauri, or dzo, are females born from yak-nak mating with lowland cows. A lang is a Tibetan bull, while a female calf born from a lang is known as a dimzo. A calf born from a yak and a lowland mountain cow is a urang. The dwarf lulu found in the districts of Mustang and Manang is a mixture of lowland cattle with yaks.

A recent decline in the population of purebred yak-nak, coupled with the difficulty in accessing Tibetan bulls, means that farmers now have more urang than dimzo. In addition, male calves known as jopke or tole — born from crossbreeding — cannot continue the generation and are used only as pack animals in the high Himalayas.

“A nak gives at most two litres of milk a day, while a chauri can produce as much as six litres daily,” explains yak researcher Shanker Raj Barsila. “If we had facilities for genetic studies, we could improve the hardiness of the species. Yak milk has medicinal properties and is generally healthier than dairy milk.”

Image by Kunda Dixit/Nepali Times, used with permission.

Besides the changing lifestyles of local populations, outmigration, and lack of access to traditional pastures in Tibet, Barsila points to inbreeding as the main challenge facing Nepal’s yaks. This is manifested in yak-naks being more prone to disease, a reduction in milk production, and yaks lacking horns.

Explaining that the agricultural census mixes up different types of yak, Barsila estimates that contrary to the figures, there are only about 20,000 yak-nak, and 40,000 to 60,000 chauri — numbers that are declining further because of climate breakdown, which is warming the mountains and affecting pastures due to deficient snowfall in winter.

“The snow that should fall from October to November now falls in March to May, and the wind blows in January to February.” Yadav says. “And all winter, there is just dry, cold wind.”

Human outmigration is directly linked to declining yak herds. Young people leaving mountain villages for Kathmandu or abroad means the next generation is not following the ancestral occupation of pastoralism, and fewer yaks place the intangible heritage of yak-rearing within a pastoral culture — complete with festivals, local diet, vocabulary and intimate knowledge about the habits of the animals — in danger of being lost forever.

Yak milk is hardened into chhurpi, a traditional cheese that preserves dairy protein for times when milk is not as plentiful. Yak milk is also used in brewing salty Himalayan tea favoured by people of the higher altitudes, and its butter is used for sacred lamps in monasteries. Yak hair is woven into woollen clothing and blankets, and yak meat is consumed.

“The domesticated yak is now becoming an endangered species due to migration from the mountains and shrinking grazing areas due to environmental impact,” says Prajwal Sharma of the International Organisation for Migration (IOM), who recently researched the impact of migration on yak rearing in Helambu, north of Kathmandu.

During his field research, Sharma observed that the number of farmers moving to high pastures with their herds in the summer — and descending to lower elevations during winter — has decreased. In Syangboche, meanwhile, Yadav has observed changes in the pasture grass because of years of winter drought.

Image by Kunda Dixit/Nepali Times, used with permission.

The mating season of the yak-nak has also been affected. “Earlier,” Yadav explains, almost all nak conceived on time, but now there are seasonal changes. Mating season used to be July to August; now it is October to November.”

Additionally, the pastureland where grass used to grow in April was barren. In Yadav’s experience in recent years, grass and herbs have only started sprouting from May to June.

The Syangboche centre sells yak milk, but the income is not even enough to buy potatoes for the yaks, let alone conduct genetic studies. The National Animal Breeding and Genetic Research Centre is supposed to study indigenous and local animal breeds, but its chief, Sagar Paudel, says there has been no study of the yak-nak inbreeding problem.

The National Cattle Research Program, located in Rampur in the district headquarters of Chitwan, has surveyed yak-nak in Rasuwa and Mustang to find out more about their adaptability to climate change, but there is no detailed genetic study planned.

Further research could help find ways for yak-nak and chauri to adapt to both weather extremes and a heating Himalaya mountain range.