Twice a year, hundreds of thousands of avian visitors gather at the Yalu Jiang Estuary Wetland National Nature Reserve, a 50-or-so-kilometer (31-mile) strip of protected mud flats in the eastern region of China, close to the North Korean border. Once there, the birds can gorge on clams and relax before setting off on the next leg of their migratory journey.
But this year, the combined toll of an extremely frosty winter (the coldest in decades) and years of man-made pollution and environmental degradation has resulted in a severely depleted seafood supply. Today's clam population is just 5 percent of what it used to be and it is certainly not enough to feed the 250,000 or so shorebirds, including the bar-tailed godwit and great knot, expected to drop by the reserve between March and May during the spring migration.
If nothing is done, the harsh reality is that thousands of the birds could starve to death, so wildlife experts in the area have come up with a radical solution: a very, very big birdfeeder.
"Drastic problems call for drastic measures," David Melville, a coastal shorebird ecologist from the Pukorokoro Miranda Shorebird Centre in Auckland, New Zealand, told reporters at ABC News.
The Pukorokoro Miranda Shorebird Centre is currently working with the Yalu Jiang National Nature Reserve in an international effort to raise funds to build "the world's biggest birdfeeder", which once completed will be kilometers long and wide. About 500 tonnes (550 tons) of farmed shellfish will then be dropped into the estuary for the shorebirds to feed on. So far, enough has been raised to feed the birds for at least three weeks.
"We have a choice, yes we could let nature take its course and we could watch a critically endangered species get even more critically endangered," Melville added.
"Or we could choose to intervene for what hopefully will be a one-off event and put supplementary feed out this year to tide over part of the population so they can migrate and breed successfully."
The endangered species Melville refers to is the great knot (Calidris tenuirostris), a short, plump migratory bird that splits its year between Siberia and Southeast Asia or Australia. Populations of the bird have been decreasing and there are now thought to be just 380,000 great knots in the wild.
Surveys have shown that the Yalu Jiang Estuary is the species' single most important stopover site so the move could be crucial to preventing numbers from declining even more than they already have.
