(PhysOrg.com) -- Can you imagine living your whole life in summer? In one of the most spectacular wildlife migrations on the planet, millions of shorebirds do exactly this by making a 20,000km round trip from their Arctic breeding grounds to wetlands in the southern hemisphere and then migrating north again each year.
Dr Richard Fuller from UQ's School of Biological Sciences is one of the researchers seeking to better understand the process .
“Australia is the end-point of one of these migration routes, the busy East Asian-Australasian Flyway, which connects us with a dozen Asian countries,” Dr Fuller said.
“This amazing wildlife spectacle is under threat.
"Some species using the flyway have declined enormously over the past couple of decades, with millions of birds being lost.
"Two of the commonest species (great knots and eastern curlews) are currently being considered for admission to the red list of species threatened with global extinction because they have declined so fast and so dramatically.
“What has caused these declines is not clear. There has been considerable loss of wetlands in Australia, but these appear not to be dramatic enough to explain the declines in migratory shore birds.”
But, according to Dr Fuller, there is another, more worrying possible explanation for the declines. During their migrations, the birds stop at “refuelling” sites in estuaries around the Yellow Sea, but these estuaries are rapidly disappearing because of land reclamation projects as the region undergoes an economic boom, he says.
“One of the biggest projects is at Saemangeum, South Korea, where construction of a 33km seawall has converted 40,000 hectares of prime estuarine habitat in to dry land," Dr Fuller said.
"It is estimated that approximately 100,000 birds could have been lost as a result of this development alone because they no longer have a place to refuel on their migration.”
“Conserving migratory animals is extremely hard because they fly across international borders. Robust international policies are needed to ensure protection of the whole migration route, because the whole system is only as strong as its weakest point.”
However, there is hope. Australia had signed bilateral agreements with Japan, China and South Korea aimed at protecting habitats for migratory birds, Dr Fuller said.
“The University of Queensland is working alongside Australian state and federal government to try and understand the causes of the birds' declines, and to discover solutions before it is too late to save one of the world's most spectacular migrations,” he said.
Explore further: Dwindling wind may tip predator-prey balance