Date: Monday, November 7, 2016
Project: Eastern Australian Waterbird Survey
Observer: Richard Kingsford
We headed for the Lachlan River and its floods, via Griffith to refuel and have lunch. It was slow going heading west into a 22 knot southwesterly head wind. We flew past Barrenbox Swamp which is now a highly regulated storage, killing off its trees.
Barrenbox Swamp made into a storage for irrigation tail water
The Lachlan River flood spreads out into two main branches: Booligal Creek and the main stem of the Lachlan River onto a vast floodplain. For our survey today, we concentrated on surveying the Booligal system with its associated distributary creeks: Merowie and Merrimajeel Creeks.
urveying the intricate channel system of the Booligal Creek system
There were more waterbirds using these channels than we had seen on any of previous floodplains or wetlands that we had surveyed this year. There pairs of ducks lurking everywhere, reflecting the productivity of this system. Then we surveyed a massive colony of mostly straw-necked ibis. It is hard to know just how large these colonies are because there are so many birds sitting on nests – tens of thousands. From the air the size of the colony was particularly impressive casting a brown stain across the green floodplain.
Vast colony of straw-necked ibis on the floodplain of the Booligal Creek system
Straw-necked ibis breeding in a massive colony
As well as the extensive floodplains and channels, the Booligal system also has swamps and lakes. The lakes were all full but didn’t have that many waterbirds. There were plenty of adjacent productive floodplain areas. These lakes become particularly important once the floodplains dry out.
Surveying one of the full lakes on the Booligal system
Everywhere between the lake and swamps, there were these complex channel systems, extending in all directions – a web of water invading the dry landscape.
Web of channels extending across the Booligal floodplain
The Booligal channel system and floodplain
We completed ten transects across the floodplain which took us about four hours from when we took off from Griffith. We stayed overnight at Swan Hill in Victoria.