Resting birds at threat by man’s best friend 

The Great and Red Knots grow their colourful breeding plumage before their return flight to the northern hemisphere to breed. Photo: David Webb

The impacts of dogs on wildlife has long been a contentious issue and now a Charles Darwin University Honours student wants to warn Territorian dog-owners about their potential impacts on migratory birds arriving in Darwin for the wet season.

After flying up to 11,000km, some migratory shorebirds find their resting place on a 1.5km stretch of beach in the northern suburbs of Darwin between Lee Point and Buffalo Creek.
Up to 4000 birds congregate to roost in the area when the high tides peak and most of their habitat and feeding area in the intertidal zone is inundated with water.

CDU Honours student Amanda Lilleyman has been observing the shorebirds in the area as part of her study into their migration patterns and behaviour.

Of the migratory shorebirds she studies in the area, the Greater Sand Plover has been observed to return to the area annually to roost.

“Most migratory shorebirds are faithful to sites, which are chosen based on past experiences, such as flying to the area with their parents and flocks, along with other environmental factors such as food security and access to safe roosting sites,” she said.

“From the Arctic, Siberia and China the birds follow the summer season in a figure eight pattern called the ‘Fly-way’ to the southern hemisphere and new feeding grounds in Asia, Australia and New Zealand.

“The birds arrive in Darwin in August and disperse throughout various locations until returning in March and April before beginning their long flight back to the northern hemisphere to breed.”

Amanda said people could help by watching out for the birds that remained in Darwin.

“During their stay in Darwin the bird’s plumage is dull in colour and hard to see at low tide, so we are asking people to take care not to disturb the birds in the area,” she said.

She said the main reason for leaving the birds in peace to roost was to let them restore their energy reserves.

“The birds need to double their fat percentage to give them enough energy for their return flight,” she said. “If they are forced to expend energy by taking flight to escape potential predators such as humans or dogs, they may move to a less favourable site, without the resources to repair their energy levels in order to complete their migratory cycle.”