An estimated 68,000 native birds are killed in New Zealand by introduced predators every night
By removing possums, rats and mustelids from the area, native species like tīeke (saddleback), hihi (stichbird), kākā, kākāriki and toutouwai (North Island robin), which are already naturally colonising suburbs near Zealandia, will find safe habitats to thrive. While this project is focused on removing predators we hope that community groups will become inspired to pursue bird translocations as their suburbs become predator free.
Not just birds, lizards too
The Wellington region has 17 native lizard species, although one of these (the robust skink) is no longer found in the region, and several others are only living on offshore islands where there are no predators.
There are two types of lizards – geckos and skinks, known to Māori collectively as mokomoko. Once you know the difference, they are easy to tell apart. Skinks have scaly skin and narrow heads like a snake, while geckos have soft velvety skin, a defined neck and much larger eyes.
Tuatara are quite different. They are very early ancestors of modern lizards. Although now very rare, they were once seen throughout the country. In Wellington, tuatara are now only found in places where pest predators are intensively controlled, including at Zealandia, Nga Manu Nature Reserve and on some offshore islands.
Lizards live in all different environments, from rocky coastal scree slopes to wetlands and forests. In this region, we have our own arboreal (tree dwelling) lizard, the Wellington green gecko.
You might even see native lizards in urban gardens. They will do much better if we can reduce the pressure of mammal predators and provide good habitat for them.
What’s so bad about rats, stoats and possums?
Rats, stoats and possums kill millions of native birds every year and have pushed species to the brink of extinction. Managing just these three predators for agriculture and conservation costs over $70 million each year.
Rats have been introduced across the globe by human activities. They threaten the survival of many native species from invertebrates like wētā and snails to lizards and birds. Rats eat almost anything which makes them a direct threat and in direct competition with native wildlife. They are common agricultural, industrial and domestic pests and cause a lot of economic damage as well as posing a risk to human health.
Possums were introduced from Australia, and eat many native species including snails and beetles as well as native birds. Possums decimate forest canopies and compete directly with native birds like kiwi for food and resources. Possums spread bovine tuberculosis to cattle and deer, resulting in high costs and lost productivity, and also harm horticulture and commercial forestry crops.
Stoats are one of the mustelid family (along with ferrets and weasels) which were introduced to manage rabbit plagues and found an unwanted place in New Zealand’s landscape. They have caused the extinction of several New Zealand bird species and are the major cause of decline for many other species, including reptiles and invertebrates. Stoats attack defenceless young kiwi and contribute to the continuing decline of mainland kiwi populations.
How many predators are there then?
The number of pests in New Zealand is many times larger than New Zealand’s population of nearly five million. Possum numbers in 2009 were estimated at 30 million. Scientists can’t hazard a guess at how many rats there are because their numbers fluctuate wildly. In Wellington, our possum numbers are relatively low in comparison to other cities, thanks in part to the Miramar Peninsula being possum free and the work of Zealandia but they still exist. Rats and stoats are a problem just like any other city.