Artificial Roosts on Trial

Artificial Roosts on Trial

Shorebird roosts installed in Queensland

In the lead-up to migratory shorebirds’ departure on their northward migration from Australian shores, they need to eat as much food as they possibly can. Long hours spent foraging on the intertidal mudflats is necessary to provide them with sufficient energy to fuel their long-haul flight back to the Northern Hemisphere — and they need every calorie to make the flight back safely.

And when they’re not feeding, spending time at roost conserves those vital calories.

Indeed, roosting forms a crucial facet in the daily life-cycle of shorebirds. However, all along the East Asian–Australasian Flyway, shorebird habitats have been — and are still being — destroyed by coastal development, reducing the area of mudflats available for the birds to feed on and reducing the number of sites where they can rest.

In an effort to address this habitat loss, BirdLife Australia initiated a number of trials to provide artificial roosts for shorebirds, both in Australia and elsewhere along the Flyway. The success of these trials has spawned other similar trials elsewhere, with the latest site being located on Barubbra Island, near the mouth of the Burnett River at Bundaberg, on Queensland’s central coastline.

The Burnett Mary Regional Group is trialling artificial roosts at Barubbra Island to provide secure habitat for roosting shorebirds. The roosts consist of long lines of oyster bags which float at or near the water’s surface, providing a safe and reliable place for waders to rest when they’re not feeding.

The floating roosts comprise 40 pillow-shaped, mesh bags per line, each filled with up to 3 kilograms of oyster shells. The weight of the shells keeps the bags partly submerged, which prevents them from flipping over on the lines.

Forty-two species of shorebirds have been recorded using the area, and enthusiastic volunteers from BirdLife Bundaberg are assisting with monitoring which of the shorebirds use the roosts.

A similar trial, also based on BirdLife Australia’s successful ground-breaking work, is being conducted in the sheltered waters of Moreton Bay.

Experts from BirdLife Australia are providing key input into the establishment and implementation of both these trial projects.