David the 8-week-old glossy black cockatoo nestling saw the world outside his nesting box at American River for the first time this week, but he wasn’t very happy about it.
He’s one of a record 48 nestlings to be banded on the island this year and throughout his life will provide crucial data to scientists working to increase the numbers of these magnificent, endangered birds.
Kangaroo Island Landscape Board (KILB) project officer Torran Welz carefully retrieved David from his nesting box 20 metres in the air and lowered him down in a backpack to his colleague Karleah Berris.
From Ms Berris’ lap he scanned the wide blue sky for the first time before squawking incredibly loudly as he was measured, weighed, and banded with the numbered metal ring that will identify him throughout his life.
“He’s a little bit grumpy,” Ms Berris said, “but they do calm down”.
“Nearly all glossy blacks eat with their left claw,” she said as she attached a silver, uniquely number ring around his left leg.
In the future, as he eats his diet of seeds from sheoak trees, scientists and photographers will be able to zoom in on this number and record his movements.
The first KI glossies — a separate subspecies to those found in NSW and Queensland — were banded in the mid-1990s when their numbers dipped to only 158 individuals.
Before the 2019/2020 bushfire on the island their numbers had been raised to 450 thanks to predator control and the installation of nesting boxes.
There are now thought to be about 420 of the birds, with their growth slowed by the loss of habitat.
“We didn’t actually lose many directly to the fires through mortality to the fire event, but now they’re all grouped up into these tiny patches of habitat,” Ms Berris said.
“There’s really large flocks feeding on small amounts of sheoaks so it’s a little bit of a waiting game, the next couple of decades, waiting for that habitat to regenerate so that they’ve got more food again.”
In the meantime the board is planting areas of well-spaced sheoaks which will be able to produce seeds for the birds in under 10 years.
In the fire recovery areas the sheoak is rebounding thickly, in some places with up to 400 seedlings per square metre.
That might sound good, but competition slows the growth rate of the trees.
Ms Berris said previous fire data indicated the sheoaks regrowing in burnt-out areas will take about 20 years before being large enough for the glossies to feed on.
She and Mr Welz have been thinning the trees out in a pilot area, an area where the remaining trees have grown two to three times more quickly in 12 months.
But the removal of the seedlings is a slow process, taking about three days to thin an area of about 50 square metres.
“We had blisters on our hands and we’ve probably got about 2,000 hectares to go,” Ms Berris said.
A close family unit
Glossies only raise one chick per year and David will stay in his nest for a few more weeks. He will remain with his parents for a year or more.
The American River flock is one of the smaller ones on the island with about 50 birds.
The population tends to stay local, with David likely to remain in the area to raise his own chicks.
Research is ongoing, however, to see how much the flocks interbreed.
When Kangaroo Island glossies do mate it is for life, and the couples are always together except when the female is incubating an egg.
Data collected by KILB shows the male is always older, with an average age gap of about four and a half years, but Ms Berris noted that could be due to an imbalance in the population.
“There are more males than females so pretty much as soon as a female is a year old and ready to leave her parents, some handsome male will come in and snap her up. But he usually has to be a mature male,” Ms Berris said.
It’s not yet known how long the Kangaroo Island subspecies typically live.
The oldest banded bird is 25 and “still going strong”, and it’s suspected that like other cockatoos they will often live for more 35 years.
With his band in place, David is sent up the nestling elevator.
In a few more weeks he’ll leave the nest for his first flight and start exploring his home at the eastern side of the island.
“Hopefully we’ll see him again soon,” Ms Berris said.
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