New data released by Wellington City Council reveals a dramatic increase in the number of native birds counted in the city in the past 10 years.
Throughout the year, the council does five-minute bird counts at 100 stations in the city's parks and reserves.
Between 2011 and 2020 the average number of native bird species seen during these counts has risen by 50 per cent.
The kākā population has rebounded the most, increasing by 250 per cent.
Kererū are also thriving, increasing by 186 per cent, followed by tui with a jump of 121 per cent.
Wellington City Council biosecurity specialist Henk Louw said it was incredibly exciting.
"Communities are really contributing from all sides – restoration, trapping, community advocacy, everybody's getting behind it and driving this increase through work in the background and the results are showing."
Louw said the work Wellingtonians have put into helping the birds is apparent in discoveries like titipounamu (rifleman) that have started nesting on Te Ahumairangi Hill - a first in more than 100 years.
Bird sanctuary Zealandia has also played a big role in rebuilding bird populations in the capital. This is because the predator-free fence around its perimeter keeps pests out.
However, he said species such as tieke (saddlebacks), toutouwai (NZ robin) and popokotea (whitehead) still find it challenging to establish outside Zealandia's fence.
"There are various environmental factors which limit them to the Zealandia halo. Predation, food availability and natural dispersal rate are all part of it."
Other factors that have contributed to the rebound have been efforts to plant two million trees in the city, more than 9000 traps in people's backyards and council reserves, and removing 72,000 pests within Wellington city over the past five years, Louw said.
Zealandia lead conservation ranger Ellen Irwin said it's awesome to see the progress native birds are making.
"Obviously Zealandia provides a real safe place for birds to breed and thrive but there's also been an amazing amount of work done by community groups and the city council around predator control, planting and trying to make a safe space once they leave the sanctuary as well."
Irwin said Zealandia assists different species in a variety of ways.
"Something like hihi (stitchbird), they are cavity nesters and our forest isn't quite mature enough to necessarily provide enough tree cavities for them to nest in, so we provide them some nest boxes that they use during breeding season."
Irwin said kākā are also given bird boxes.
"The most important thing we do though is maintain the fence and maintain a predator-free environment."
Irwin said Wellingtonians can also take action to help native birds thrive.
"Backyard trapping is an awesome thing to do, planting native trees that help support not just birds, but lizards and other invertebrates to really create a real biodiverse backyard."
She said responsible pet ownership around reserves, especially with cats, is another key measure.
Science and communication lead ranger Gini Letham said other initiatives include the Sanctuary to Sea project, which aims to improve fish habitats, migration and forest corridors for native birds leaving Zealandia.
It's a partnership of more than 15 restoration organisations, including iwi, Morphum Environmental, Wellington City Council, Wellington Water and Greater Wellington Regional Council.
"It's about restoring the environment as a whole rather than to help a specific species."
Letham said the project, which begun in 2018, is already having an impact.
She said they are also doing a lot of work outside the fence on wildlife education for those who don't come to Zealandia often.
"Nature is for everyone so we want to make sure everyone can get access to it."