Richard Kingsford says waterbirds in Australia's eastern states are in danger due to the drought conditions. ABC News: Billy Cooper

Australian waterbird population has fallen as much as 90 per cent in Australia's east, shows 37-year study

Aerial surveys have revealed a drastic decline in waterbird numbers since 1982. The decline is linked to drought conditions, which leave water dwellers out in the dry. Poor water policy management is also partly to blame, according to one scientist

When Sydney scientist Richard Kingsford and his team from the University of NSW began their research in the early 1980s, they clocked up to a million waterbirds in aerial surveys.

"Now it's crashed to less than 100,000," Professor Kingsford said.

"While the birds could have gone elsewhere, it's most likely that they've died."

Professor Kingsford said spoonbills, ibis and egrets are among those species in danger from long, dry drought conditions.

The ABC joined Professor Kingsford and his team for a day of aerial surveys west of Moree, around the Gwydir Wetlands.

The research involves six weeks of aerial surveys of swathes of land to determine the population and species of birdlife in eastern states.

Professor Kingsford said in a good year the wetlands would be filled with birds.

"We're seeing much bigger [declines] than I would have expected and that's on the back of 70 per cent declines over the 37 years that we've been doing this survey," he said.

"It is grim, many of the rivers are dry … as everybody knows we've got this gripping drought across the Murray-Darling basin and up into the north and we're just not seeing any wetlands."

The picture is grimmer at another internationally-renowned breeding ground for birds, the Macquarie Marshes, in north-western NSW.

Bushfires ravaged this area in the past few weeks, and where once there were thousands of birds counted, this year the team counted only one black duck.

Read full article . . .