Two centuries of urbanisation has created a little-known housing crisis across inner Sydney.
As buildings went up, large trees that served as homes for cockatoos, owls, possums and bats have come down.
So urban ecologists are stepping in to help.
Over the past month, more than 60 nesting boxes have been placed high in trees dotted around some of the city’s best known green spaces including Hyde Park, Victoria Park and Prince Alfred Park.
Hollows that these creatures would traditionally have called home can take 100 years to form in mature trees. While the city keeps planting trees, it will be a while before they yield a decent habitat.
The City of Sydney’s urban ecologist, Dr James Macnamara, and his team have taken matters into their own hands in the hope that “if we build it, they will come”.
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“Over the last 200 years of urbanisation, we’ve taken out a lot of the large trees which, as they get older, should form hollows where animals can nest, lay eggs and have young [offspring],” he says.
“But it takes upwards of 100 years for a properly sized hollow to form … so we’re installing some real estate for our feathered and furry friends.”
He says “biodiversity is critical for maintaining a healthy and diverse ecosystem” so anything that could boost it was good news.
The new boxes add to the 43 that were previously placed around Sydney Park, Federal Park and Blackwattle Bay last year.
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Macnamara says the science “is a bit hit and miss” on the effectiveness of the boxes, but early signs for the project have been a source of hope.
A survey done towards the end of last year on the boxes already installed found a family of possums in one box. There are also signs the boxes were being used.
The lord mayor of Sydney, Clover Moore, said the project was about making the city as good for animals as it was for people, while continually improving central green spaces.
“Our parks are not only the green lungs of city for the enjoyment of the people but they are also homes for our flora and fauna,” she says.
The boxes vary in size and style, depending on the creatures they hope to house.
Among the birds expected to give the hanging homes a try are yellow-tailed black cockatoos; powerful, barn and boobook owls; and red-rumped parrots.
It is hoped they will also provide shelter for microbats, skinks and possums.
People like Macnamara will visit the boxes periodically to check for signs of use and monitor for pests who also might like to stop by.
But that doesn’t include snakes, which the urban ecologist said would be welcomed should they choose to visit.
“It’s not good or bad. It’s a natural system,” Macnamara says.
“Snakes need a place to live as well, as much as we do.”