Conservation is taken very seriously here; until last year there was no electricity in the valley because of the fear cranes would become tangled in the wires. Electric light and other mod cons have finally arrived now however, but via underground lines.
When we arrived in the valley the day before we were told five cranes were already in residence and more could be expected any time. We'd seen the early arrivals as we'd driven from our lodge up to the gompa or monastic complex, their white bodies contrasting with the jet black neck feathers, long legs carrying them across the swampy ground.
Although birds and locals live harmoniously in the valley, bird-watchers are kept at a safe distance - there's a crane information centre equipped with powerful binoculars from which to view them.
But there's also a nature walk that begins at the monastery, which sits perched on a promontory at the head of the valley, then snakes down to the valley floor and winds its way along the hills just above the cranes' favourite feeding area. Maybe, if we are very lucky they might pick their way across towards us as they search for their preferred foods, which include snails, frogs, fish and choice plant roots.
Gantey Gompa's main temple is 450 years old and ever since I first began visiting Bhutan about 10 years ago it has been under renovation. Dozens of carpenters and wood-carvers lived on site, replacing timbers attacked by beetles and creating intricate carvings of Bhutanese Buddhism's auspicious symbols such as the conch shell, mandala and endless knot and its four protective animals - the snow lion, dragon, garuda and tiger. At the height of the work, the ground around the temple's exterior walls was metres deep in wood shavings.
The work is nearly completed now; the carvings have been painted and installed on the tower that houses the central prayer hall. Little monks (they can be boys as young as six or seven) in their red robes skip around the courtyard until they are summoned by the discipline monk to continue their lessons memorising Buddhist scriptures. Cymbals clash in the dim light of the prayer hall and the air reverberates with the deep baying of a two-metre long brass trumpet.
We leave the daily rhythms of monastic life to trek downhill through pine trees festooned with ghostly grey lichens that waft in the breeze. At the forest edge we pause to look for the cranes, but there are still just five and they are steadfastly staying on the far side of the valley.
Brian, who takes superb photographs, and I have been dawdling - hopefully scanning the valley, scrutinising white blobs through our camera lenses and discovering they are stones, or pieces of sun-bleached wood. The rest of the group are well on their way back to the lodge when we reach a stone chorten (a Buddhist religious monument) that is perched on a knoll on the side of the valley.
It's a perfect morning - the chorten's whitewashed sides are radiating warmth and the mountain tops are cloudless. Ravens are wheeling above us and, who knows, at any moment more cranes might touch down from their epic flight.
So we sit, eating slightly furry jubes that I've found at the bottom of my daypack. It's nearly lunch-time and we're both wondering if we're wasting our time sitting here on the off-chance that more cranes might fly in just to suit us. We ponder why a chorten has been built on this particular knoll - did an important holy man once frequent this spot or did someone feel some especially strong spiritual energy here?
Then, for no good reason at all, I look behind me where a small high valley dotted with farms merged with the main one. Four birds are flying down it, calling. Spluttering somewhat incoherently the word "crane" at Brian I point to the sky. We both shoot to our feet, Brian's camera clicking satisfyingly every few seconds.
The four birds, necks outstretched, wings flashing white and black, legs dangling beneath them, sweep past us, then perform a graceful loop above our chorten. Then they are gone, floating to earth near the earlier arrivals.
It was, we agreed, one of those indefinably special moments; a time to be silent and marvel, to have one's soul soar just a little with the birds. Maybe the chorten-builders knew something we had not - that our vantage point lay on the equivalent of an avian runway approach and been inspired to leave a tangible reminder of an ineffably spiritual event.