Surkhet, July 13 -- For nearly two decades, 62-year-old Durga Bahadur Budha has trekked into the remote alpine meadows of Mugu every spring in search of yarsagumba (Cordyceps sinensis), the prized Himalayan fungus-caterpillar that sustains thousands of families across Nepal's Karnali province.

This year, the journey brought little reward.

Budha, from Khatyad Rural Municipality in Mugu district, set off in the third week of May with his wife Shanti and sons Gobinda and Prakash for the Thulo Koiki pasture in Mugum Karmarong Rural Municipality. After a three-day trek carrying supplies worth about Rs50,000, the family spent two weeks combing the mountainsides but collected only 210 pieces of yarsagumba.

They sold the harvest directly at th...