The destruction of tidal flats in Asia has caused a serious decline in Australian migratory shorebird numbers and could lead to the extinction of some species, a report has found.

Birds such as the curlew sandpiper and eastern curlew breed on the tundra of Arctic Siberia and fly to Australia in the antipodean summer.

On the way they stop off in China, Korea and other east Asian countries to refuel.

The report based on University of Queensland research found 65 per cent of tidal flats in east Asia had been destroyed by urbanisation, farming and pollution.

The main refuelling area for migratory shorebirds is the tidal flats of the Yellow Sea, east of mainland China and west of the Korean peninsula.

Millions of shorebirds use the area to feed on their annual round trip.

The bar-tailed godwit shore bird (pictured on Thompson Beach north of Adelaide) breeds on Arctic coasts. ( Supplied: Peter Corcoran )

The research suggested these important ecosystems were at risk of total collapse because of coastal development, widespread pollution and algal blooms, researcher Dr Nick Murray said.

Without these feeding grounds, birds cannot make the several thousand kilometre return trip, he said.

"We found that about 65 per cent of those habitats have disappeared," he said.

"What that means for migratory shorebirds is there have been large population declines because they no longer have a fuel stop on their migration."

Dr Murray warned that previously common migratory shorebirds were in serious decline.

"Across Australia we are seeing declines in several species of migratory shorebirds," he said.

"In fact the Federal Government is assessing two of these species to be listed on our national environmental legislation as endangered.

"The curlew sandpiper and eastern curlew are migratory shorebirds that come to Australia in our summer and as they migrate back to Asia, they need to rest and refuel.

"The decline that we have discovered means they have nowhere to stop and get the energy they need to continue the journey back to their breeding sites."

Curlew sandpiper and eastern curlew populations each crashed by about 70 per cent over the past 20 years, according to the National Environmental Research Program.

Bird watchers also reported a drop in bird numbers.

The numbers of migratory shorebirds visiting the Hunter River estuary region in New South Wales were down by two-thirds in 15 years, according to the Hunter Bird Observers Club.

"There'll be virtually an insignificant number of migratory shorebirds in the estuary during the next 10 to 20 years," the club's president predicted last year.