Back to nature – boosting biodiversity
In these unique islands, home to plants and animals found nowhere else in the world, we humans have wreaked havoc.
In creating cities, towns, and even intensive agriculture and horticulture, we have lost many natural habitats in New Zealand, while other have become fragmented.
Tourists come to New Zealand to experience our unique, extraordinary, and beautiful environment – but more than 80% of the large street trees in Christchurch are exotics.
Worldwide, 146 cities are in or close to biodiversity hotspots, where endemic species (native species found only in that place) are experiencing exceptional loss of habitat. New Zealand is one of those hotspots. Christchurch is one of those cities.
Yet Christchurch has great potential to not just preserve, but restore biodiversity. It is regarded by many as the wetland bird capital of New Zealand. It is also home to regionally vulnerable species such as manuka, a species of spider orchid, a native sundew and the endemic flightless crane fly. Recently a rare spotless crake was recorded at Travis Wetland, and two Australasian bittern chicks were discovered nearby. Yet most of our forest birds are missing.
Since the earthquakes kotuku have been seen at Travis and Bexley wetlands, Australasian bitterns have made Bexley Wetland their home, and New Zealand falcons have been seen in the Avon River Red Zone.
Natural regeneration was already happening in Christchurch before the earthquakes. But since the earthquakes, where nature has been left to get on with it, that regeneration has been turbo-charged.
In plots of red-zoned land managed by volunteers (where first CERA and now LINZ are not grassing and mowing) there are large numbers of self-seeded cabbage trees, ribbonwood, kowhai, ake ake, coprosmas, pittosporums and many others. In one spot alone, volunteers have counted 21 native species.
But we can do even better. Size matters to biodiversity: the larger the area of restored habitat, the richer the outcome, for wildlife and humans. Species that are limited to small, isolated pockets of habitat are at risk of disappearing from Christchurch.
If we want kereru, tui, New Zealand falcons, harrier hawks, bellbirds, fantails and other native birds to become common in Christchurch, we need to provide a place for them to live. Fleshy fruit and nectar-bearing native species (and a few exotics) are vitally important to them. If we plant the trees, the birds will follow.
The Avon River Red Zone provides an unmissable opportunity to return habitat and restore biodiversity, helping to bring some of our endangered native species back from the brink and into our city.
On the next page: Urban oasis