Bumdeling Wetland

Bumdeling Wetland is a 142-hectare marshland in Trashi Yangtse District, northeastern Bhutan, lying within the Bumdeling Wildlife Sanctuary (BWS). The wetland is one of two principal wintering grounds for the endangered black-necked crane (Grus nigricollis) in Bhutan, the other being Phobjikha Valley in Wangdue Phodrang District. The broader sanctuary spans 1,520.61 square kilometres at elevations ranging from 1,500 to 6,000 metres. The wetland sits on Bhutan's tentative list for UNESCO World Heritage designation.^[1]

Black-necked Cranes

Black-necked cranes migrate to Bumdeling from their breeding grounds on the Tibetan Plateau, arriving in late October and departing by mid-February. The wetland provides roosting and foraging habitat — the cranes feed on waste grain in harvested rice paddies, tubers, and invertebrates in the marshy ground. In the 2024–2025 winter survey, the Royal Society for Protection of Nature (RSPN) recorded 59 cranes at Bumdeling, including seven juveniles.^[2]

Bhutan's total wintering crane population across all sites — Phobjikha, Bumdeling, and smaller roosts at Khotokha and Bumthang — has shown an overall increase in recent decades, reaching over 700 in the 2024–2025 count. However, RSPN records show that numbers at Bumdeling specifically have fluctuated, with a gradual decline compared to earlier years. The RSPN attributes localised declines to habitat degradation, increasing human activity near roosting sites, eutrophication of wetlands, predation by stray dogs, and changes in agricultural practice (particularly the shift from rice to cash crops that reduces post-harvest foraging habitat).^[3]

Biodiversity

The wetland and the surrounding sanctuary support an exceptionally diverse biota. Published inventories document approximately 100 mammal species, 432 bird species, 650 plant species, 46 orchid species, 130 butterfly species, 29 dragonfly species, 45 herpetofauna species, and 7 fish species within BWS. Among the sanctuary's rarest inhabitants is Ludlow's Bhutan Swallowtail (Bhutanitis ludlowi), a butterfly species endemic to Bhutan — and indeed the only butterfly species endemic to the country. Other notable species include the red panda, Himalayan black bear, capped langur, and rufous-necked hornbill.^[4]

Conservation Challenges

Conservation at Bumdeling must balance crane habitat protection with the needs of local farming communities. Rice paddies adjacent to the wetland are integral to crane feeding patterns, but they also represent livelihoods for hundreds of households. Crop damage by cranes creates tension, though a compensation scheme administered by RSPN and the local government has helped manage conflicts. Phurba Wangdi, a 65-year-old Bumdeling resident, has worked for decades as a volunteer crane caretaker, monitoring the birds and reporting to RSPN during each wintering season.^[5]

Broader threats include infrastructure development near the wetland, the conversion of paddy fields to other land uses, climate-driven changes in hydrology, and the expansion of Trashi Yangtse town. The Black-necked Crane Conservation Action Plan for Bhutan (2021–2025), published by RSPN and the Department of Forests and Park Services, outlines measures including habitat restoration, community engagement, stray dog management, and research on crane ecology.^[6]

Visitor Access

Visitors can observe the cranes during the winter months (November to February), typically from designated viewing points to minimise disturbance. The RSPN operates a crane information centre near the wetland. Trashi Yangtse town, the district capital, is the nearest service centre with accommodation and transport connections. Access to the district is by road from Trashigang, approximately four hours' drive.

References

1. Bumdeling Wildlife Sanctuary — UNESCO World Heritage Centre, Tentative Lists
2. Black-necked Crane — RSPN Bhutan
3. Bhutan's black-necked crane population increases but key habitats see decline — Asia News Network
4. Bumdeling Wildlife Sanctuary — Wikipedia
5. Crane caretaker Phurba wins Regional Crane Conservation Award — RSPN
6. Black-necked Crane Conservation Action Plan for Bhutan 2021–2025 — RSPN/DoFPS