Bringing tui back to the city
The rebuild of Christchurch provides a chance to attract tui back to the city - if people grow the right plants to feed them, writes Alison Evans.
The earthquakes in Christchurch have caused chaos, let's face it. There are houses being demolished by the hour - and disappearing with them are the mature gardens that once supported an array of flowering plants used by birds and insects.
Many of the old kowhai, flax and cabbage trees have been uprooted and disposed of. But if we want to see tui and bellbirds settling in Christchurch, we need to replace these plants. Many sections are now empty awaiting new dwellings, or are covered with expansive new houses. Even where some thought has been given to planting new trees, these trees will take 10 years or more to be useful to the birds that live in our city.
Promoting bird friendly plantings is one of the aims of the Greening the Red Zone group, which is focused on restoring habitat for tui and other native birds, so they again become common throughout Christchurch.
Before humans arrived, the area now occupied by Christchurch City was inhabited only by native plants and animals.
"We really want to see a meaningful space made for those plants and animals to return," said Ashley Campbell, who has been instrumental in forming the Greening the Red Zone group.
Restoring the natural habitats in the Avon River red zone isn't about getting rid of the city's beautiful exotics, but rather adding back something that's missing - the habitat our native birds can thrive in.
We already have an example of how that can happen, right on our doorstep.
In 2009 and 2010, the Banks Peninsula Conservation Trust took on an ambitious project to return tui to the peninsula, after they disappeared about 20 years ago.
The Banks Peninsula Tui Restoration Project grew from an idea originally proposed by Ngai Tahu to return tui as part of the original ecology of Banks Peninsula.
In total, 72 tui were brought from Maud Island in the Marlborough Sounds and released at Hinewai near Akaroa. Over the past four or five years the number of tui has been gradually increasing and the hope is that they will soon start to move back into Christchurch city.
Tui are no strangers to city life. They are quite common in other New Zealand cities, including Auckland, Wellington and Nelson. Tui are present in the Canterbury foothills but because the plains have lost the vegetation corridors that are important "highways" for birds to move along; they have not made their way back into Christchurch.
Both tui and bellbirds are nectar feeders, meaning that they rely on flowers that produce nectar, such as fuchsia, kowhai, cabbage tree and flax. They also use the flowers of exotic trees and shrubs such as eucalyptus, wattle, protea, waratah, red hot poker flowers and bottle-brush.
One of their all-time favourites are trees in the Myrtaceae family, such as Pohutukawa and rata. The key to getting a year-round population of tui and bellbirds in the city is to have trees available that provide nectar at different times of the year.
There have been a several sightings of tui around Christchurch but they seem to be tourists rather than permanent residents. Tui are certainly capable of flying reasonably long distances and there have been sightings in Governors Bay, Cashmere and Rolleston. One of the tui from the peninsula flew all the way to Leithfield Beach and then gradually made its way back to Akaroa again.
"They often fly across the peninsula spending a few days in one valley, then pop back across to Akaroa or one of the outer bays," said Dr Laura Molles from Lincoln University, who has been leading the work. All of the original translocated tui have coloured bands on their legs, which helps the trust recognise individual birds.
Many of the birds sighted now are unbanded, which is a good sign and means that they are most likely peninsula born and bred.
To encourage tui to stay in Christchurch there needs to be sufficient food supply and habitat for them all year round. Christchurch City Council is working on improving the vegetation corridors for birdlife around the city, but it also needs to accommodate issues such as bank stabilisation, creating safe walking areas, cultural interests, privacy issues and retaining landscape character.
"Planting trees that produce nectar such as kowhai can give tui a real boost in the spring as they are preparing to breed and these trees will certainly attract their attention," says Molles.
"Once the habitat has been created for tui, we will need to look at controlling predators such as rats so that the tui can successfully breed as well," she said.
What a golden opportunity we have to replant new gardens with trees to attract tui and other native birds back into the city for all to enjoy.
If you want to help, all the hard work of figuring out what to plant and when it flowers has been done. There is a handy brochure called Tui Tucker that shows which plants are important for native birds at different times of the year available on the Banks Peninsula Conservation Trust website (www.bpct.org.nz).
You can also report tui sightings on our text-a-tui hotline 027 949 5886, with details of where, when the tui was sighted and what colour any leg bands are. And you can also enter (and view) sightings, including photographs, on the NaturewatchNZ website or iPhone app.
Alison Evans is an ecologist, science writer and volunteer for the Banks Peninsula Conservation Trust.
- The Press