How to help one of Australia’s rarest birds save itself from extinction

How to help one of Australia’s rarest birds save itself from extinction

09/05/2021

The 40-spotted pardalote’s instinct to feather its own nest is the key to a plan being hatched by canny scientists hoping to stop one of Australia’s rarest birds from disappearing forever.

Once common across its native home in Tasmania’s white gum forests, the pardalote has become endangered through habitat loss. It clings onto a sliver of its former range in Flinders, Maria and Bruny islands.

A clutch of pardolote chicks easily fit into human hands. Credit:Fernanda Alves.

Its fight for survival has become even more critical in recent years as a gruesome blood-sucking parasite has begun to kill more than 90 per cent of newborn chicks.

But scientists are helping the species fight back by tapping into its instinct to collect feathers from the forest for nesting material.

Australian National University researcher Fernanda Alves, from the Fenner School of Environment and Society, uses chicken feathers treated with insecticide to fumigate the pardalotes’ nests and kill the parasitic larvae of a native fly.

40-spotted pardalotes use feathers they find in the forest for nesting material. Dispensers loaded with fumigated feathers are an efficient way to move insecticide into their nests.Credit:Fernanda Alves.

Like many birds, the 40-spotted pardalote’s diet includes manna, a sugary secretion from white gums, but they are unique in being the only species that farms the food source by making nicks in the foliage with their beaks to stimulate production.

National Threatened Species Day on September 7 was established to promote the urgency of Australia’s battle against extinction. About 100 of Australia’s unique flora and fauna species have been wiped out since colonisation, and that rate of loss, which is as comprehensive as anywhere else on Earth, has not slowed over the past 200 years.

Ms Alves said it was not clear why the native parasite had suddenly become such a problem, but it was probably linked to the drastically reduced population of the species.

Initial investigations showed the insecticide was very effective in killing the parasite, but Ms Alves knew it would be too much work to hunt down every nest, climb the tree and treat it.

But she remembered a technique that had been used in the Galapagos Islands to help Darwin’s finches fight off a nest parasite. Darwin’s finches are known to pinch clothing that had been hung out to dry and use it for nesting material. Treated items were strategically placed around the island where they would be found by the finches, who unwittingly transferred insecticide back to their nest.

Ms Alves transferred the idea to the pardalote’s forests and experimented with feather dispensers.

The 40-spotted pardalote are unique in using their stubby beaks to “farm” manna – the sugary secretion from white gum eucalyptus trees. Credit:Fernanda Alves.

“The idea was to transfer the hard job, which is to get up a tree. During the breeding season, they’re looking for nesting materials. In the beginning, it was just a hope, fingers crossed, that they are actually going find it,” she said.

Feather dispensers were trialled using a $235,000 grant from the federal government, and now 95 per cent of newborn chicks survive in fumigated nests.

More funding will be needed to roll the protection program out at scale, Ms Alves said, with the ultimate goal of reintroducing the birds to mainland Tasmania: “We’re just scratching the surface now.”

“To see these brilliant results using such highly effective and inexpensive conservation methods bodes well for the pardalote’s future,” said federal Environment Minister Sussan Ley.

“Since 2014, we have invested more than $560 million for projects supporting outcomes for threatened species. We are working with leading experts, scientists, traditional owners and local community groups on the ground to help our habitat and wildlife to recover.”

Liam Mannix’s Examine newsletter explains and analyses science with a rigorous focus on the evidence. Sign up to get it each week.

Most Viewed in Politics

From our partners

Source: Read Full Article