Once upon a time, New Zealand hosted a variety of bird life unseen anywhere else on the planet. The birds were everywhere and everything, in all different sizes, shapes and colours, filling the forests with songs so loud they could be heard from miles offshore. Today, many of the forests we walked through are silent. On the shoreline only the thunder of the waves echoes in the distance. What happened to these magnificent creatures?
You might have noticed that on several occasions we’ve written about the birds of New Zealand. The battle for the birds has become such a big part of our TA experience, and a story we both attach importance to, so we found it is time to write it down in full. Now, we are, or were, not people keen on bird watching. We always liked hearing them sing in our vicinity but who was who and what they looked like were questions that did not enter our minds.
This changed when we came to New Zealand. Very early into our hike the unique sounds of New Zealand’s birds caught our attention. We started picking up on their history. While numerous people and DOC pamflets put the puzzle together, the story started moving us. We feel attached to this place, and to its inhabitants. We learned who is who – the tui, the bellbird, the kea, the fantail, etc. – we learned who is around, and who is no more.
85 million years ago New Zealand split off from the supercontinent Gondwana, and another 30 million years later it was seperated from Australia by over 2000km of water. While in the rest of the world mammals started evolving and became dominant after the extinction of the dinosaurs, New Zealand missed this mammalian evolution in its isolation. Instead, the land became dominated by birds, who shared the land with insects, reptiles and three species of bats, the only native mammals in the country.
The birds filled all the niches. The birds were the grazers, the hunters, the browsers. They adapted to a forest-rich and mammal predator-free environment. Many of them did not see the purpose in flying anymore and became clumsy at it, while others simply evolved into flightless birds such as the takahe and the weka. They build nests on the ground, and even flying birds like the kea do so. The kiwi and the kakapo took it another step further and became nocturnal animals as well. Many native bird species developed a defence system in their feather cover, mingling in the forest cover perfectly. If they would stand still and freeze, danger would simply pass them by.
The unique forests of New Zealand are closely related to the forests of Gondwana, containing some of the most ancient plant species found on Earth (more than once we commented that we were walking around in Jurassic Park). 85% of New Zealand was covered in them, from the mighty kauri forests in the north to the rimu and beech cover in the deep south. Under their canopy plants found their respective place in the foliage. Fern trees, vines, orchids, fushia, funghi and mistletoes thrived underneath the roof of leaves, creating a rich but delicate forest.
The birds depended on the forest for their survival and vice versa. Everyone had a very specific function, and the bird species were very specialized in their environment. This made them vulnerable to change: highly specialized species who live in a limited range only easily come under pressure when they need to adapt. It is thus no surprise that when humans came and disturbed the balance, things went downhill fast.
The Maori cleared large areas of lowland forest for their gardens and brought kuri (pacific dog) and kiore (Polynesian rat) with them for food. While the kuri and the kiore started predating the birds the humans hunted them as well for food and to use their feathers to make cloaks. Even though their hunting was mostly done sustainibly to ensure resources for years to come, overhunting and deforestation caused the extinction of certain species such as the iconic moa and the giant Haast’s eagle.
The biggest impact came with the arrival of Europeans. To satisfy the growing demand for timber large areas were cleared of their forest cover: the kauri forests almost vanished, and about 1% of lowland forests remains on the north island today. After the biggest trees were brought out, the remaining forest was burned to create grazing grounds for pasture.
The Europeans also introduced a large number of animals that have devastating effects on the birds. They brought goats, pigs, cats and dogs with them. Rats and mice came over with the ships and rapidly spread over the country. Rabbits became an enormous problem, even pushing farmers off their land, so stoats and ferrets were introduced to cope with them. Possum were introduced for their fur, while several species of deer were released for sport hunting.
The native birds, bats and insects had no defences against these new predators. The freeze and disappear tactic did not work against a cat with a well-developed sense of smell. Stoats and ferrets took on the birds rather than rabbits, being a much easier prey. Mice will eat fruits, seeds and insects, competing with birds and disturbing the regeneration of the forest. Possums destroy the forest raging for mistletoe, rata and rimu fruit, killing of trees and leaving little for nectar loving birds like the tui. Tui who will pollinate the flowers while looking for food, while over-foraging by possums destroys the plants. Just like rats they plunder nests for eggs and bird chicks, endangering adult female birds defending their nests as well. Wasps thrive on honeydew, taking away the feast that used to offer plenty for all. And none of these introduced species have natural predators, leaving them free to rage on New Zealand’s native species.
The consequences are vast. Deer take away foliation in the forest, eating away everything from the middle to the bottom. The mistletoe and rata have become rare due to possum activity. The forests look neither sound the same. There is little food for the birds, and those who manage to find it are under threat from attacks by predators. In Captain Cook’s day the birdsong of New Zealand could be heard from 3km offshore, and his men retreated to the ship after being uncapable of sleeping under the birdsong at dawn. Speaking at dusk or dawn was impossible.
Thousands of birds used to fly over the rainforests of the fiords, all we saw were three shags. Unique species like the kea, the whio and the kaka are only a few thousand strong. Together with the birds, the bats, weta’s, and reptiles such as the gecko and tuatara are struggling. The kakapo, once one of the most common birds of New Zealand (one settler quoted that “you could shake a tree and they would fall down like apples”), is now confined to a few offshore islands. Today, there are 140 kakapo’s left in this world.
Half of New Zealand’s bird species have disappeared. For the remainders, the battle is on. Already in the 50’s the government payed deer and possum cullers to keep the populations under control. Today individual volunteers, local trusts, companies and scientific institutions support the work of the DOC to protect what is left. Conservation has become one of the major keywords of New Zealand. School classes and communities are being involved to teach people why it is worth protecting their natural resources.
A vast and in places dense network of traps is used to keep pest and predator numbers low. A few islands have been made pest-free and were turned into safe havens for some of the country’s most vulnerable birds and plants. Controversial 1080 poison is airdropped in the hope to avoid rat populations from rising. Millions and millions of dollars and countless hours of personal time are invested every year to keep what is left of New Zealand’s native ecosystem alive.
Is it working? Yes. Where efforts are focused, birds pushed to the brink have revived. The forests sing again. The rata, mistletoe and orchids flower once more. Yet it will never be what it was. Islands can be kept safe and regions can be controlled, but from the vast back country not all of these introduced species can be removed. There will not be flocks of birds thousands strong swirling over the fiords of New Zealand again.
Is it worth continuing? Yes. Those areas we passed where DOC is working hard to make it happen are magnificent. The forests sing, and the birds hop around over and under their canopy.
We wrote this because we believe it is important to know. Because it is important to show more than those beautiful places we walked through, to show it all: the good, the bad and the ugly. And because unfortunately, New Zealand is not the only place where we are losing precious natural resources. In Norway and Sweden, the places we would call home, the situation is not all that much better. We can all make an impact, no matter how small. Plant native vegetation in your garden. Spread information about conservation issues. Or find out what is going on in your area. It’s that easy.
For more information on New Zealand conservation projects and organizations you can amongst others check out:
– http://www.doc.govt.nz/our-work/battle-for-our-birds/ on the past beech mast year and the predator control program
– http://kakaporecovery.org.nz/ bringing the kakapo back from the brink of extinction
– http://www.yellow-eyedpenguin.org.nz/ protecting the yellow-eyed penguin, unique to New Zealand
– http://www.openspace.org.nz/ protecting valuable forest and wetland areas
– http://www.apwt.org.nz/ kiwi and kea recovery in the Arthur Pass region
– http://www.whioforever.co.nz/nation-wide program for the protection of the endangered blue duck