Demand soars as supplies drop from loss of habitat and over-harvesting

For decades, a rare fungus, prized as an aphrodisiac and dubbed "Himalayan Viagra", has been a source of income for poor villagers in Nepal's remote Himalayan foothills.

Men, women and children stream into high meadows every year to harvest the fungus called yarsagumba, meaning "summer grass, winter worm", which grows from dead moth larvae. High-quality specimens fetch thousands of dollars a kilogram.

But experts say the fungus, found only above 3,500 meters, is under threat and yields are falling, threatening the livelihood of thousands of people who depend on it for up to 70 percent of their income.

"Over-harvesting, premature harvesting, destruction of the pastureland where it grows, and perhaps climate change are the major causes of the decline," said Uttam Babu Shrestha, a graduate student at the University of Massachusetts.

"If this continues it could become extinct soon."

The parasitic fungus yarsagumba kills and then grows on ghost moth larvae in the ground.

Although there is so scientific evidence, the small fungus is prized in traditional Chinese medicines as a tonic to increase sexual vigor.

During the annual May and June picking season, thousands of Nepali villagers travel in mule and yak trains to high pastures to look for the tiny buds that protrude from the ground.

Shrestha said villagers who were used to collecting kilograms of yarsagumba at a time 10 years ago, now struggle to gather even small amounts of the fungus, which grows to roughly the size of a potato chip.

"This year has been the worst. Many collectors in Dolpa returned without any," said Shrestha.

The area, where 50,000 people compete to find the fungus every year, accounts for more than half of Nepal's annual harvest, which topped 1,170 kilograms last year.

Demand for the fungus is soaring. Villagers received $6 for a piece of yarsagumba about the size of a chili this year - twice the amount they received last year.

In Kathmandu, high-quality fungus sells for up to $31,000 a kg.

Commercial collection of the fungus began some 30 years ago.

Nepali villager Tshewang Lama saw how some Chinese took drops of yarsagumba as tincture to increase immunity and cure tuberculosis, fatigue, paralysis and cancer.

Lama used the fungus to cure his sleep disorder and other ailments and became one of the first gatherers.

Shrestha said abandoned trash, open defecation and trees cut for cooking and heating damaged the hills where the fungus grows.

"If these are not checked, in time the environmental cost will be bigger than its economic benefits," he explained.

Officials said the Nepali government collected $132,000 from the export of the fungus in 2011, but analysts said the figures may be low because many villagers sell their crop directly to customers in China without reporting transactions.

Filmmaker Dipendra Bhandari, who made a documentary about the fungus harvest, Journey to Yarsa, said in several remote villages children accompany their parents during the picking season when schools are closed for two months.

He added that it can be dangerous, and villagers fall sick or die during the long journey.

In 2009, seven gatherers were killed in a fight with locals over the fungus in west Nepal, and two years earlier at least 16 people perished when a snowstorm buried their camp in Dolpa.

Lama believes the government should regulate trade and strengthen local institutions to ensure pickers get the maximum benefits from the trade.

"It is a money plant. We should conserve it so the harvest becomes sustainable in the long run," Lama said.