Bringing back the natives

Once the island was made predator free and the planting programme had started to create suitable habitat, animals began to return to the island and increase in number. Some made their own way back to the island while others have been translocated to the island by FOMLI. Some of the island inhabitants are described below.

Kiwi

Kiwi were first introduced to the island in 2001 when adult birds Helga and Glen were released as part of a trial to see how kiwi would fare on the island. They did extremely well, and since 2003 the island has been operating as a ‘Kiwi Creche’ for Operation Nest Egg (“ONE”) and rescued kiwi chicks. A crèche site is a predator free environment where young kiwi chicks, hatched in the wild or artificially incubated, are released to grow on without risk of predation.  Once the chicks reach 1200g or more they are then capable of defending themselves from stoats, which are the primary predator of young kiwi chicks, and can be returned to the mainland. In nine years nearly 100 chicks have ‘graduated’ from the island crèche and have been returned to the mainland. At any one time the island is home to four adults (breeding pairs Glen & Baldrick and Sir Ed and Kahui whetu) and up to 30 “ONE” chicks.

Shore birds

The island is used by a variety of shorebirds for feeding, roosting and breeding. “Nationally vulnerable” New Zealand dotterel and “At Risk” variable oyster catchers nest on the island in spring and summer. Pied shag, little black shag, “Nationally vulnerable” reef heron, white faced heron, Caspian terns and black backed gulls are all commonly seen roosting and feeding on and around the island. There are also seasonal visitors including royal spoonbills in winter and more occasional visitors such as bar-tailed godwits.

New Zealand dotterel Variable oyster catcher

Forest & grassland birds

The regenerating forest and grasslands on Matakohe are home to an ever-increasing number and variety of birds. Both banded rail and fernbird (now rare at mainland sites) self-introduced to the island once it became predator free. Both of these secretive species are now very common on the island and breed very successfully. New Zealand pipit, fantail, grey warblers, wax eyes, kingfisher and Australasian harriers are also very common. Morepork, pukeko, and shining cuckoo are more seasonal visitors. The larger frugivourous birds like the kukupa and honeyeaters like the tui are also still only seasonal visitors, as the food sources on the island continue to develop.  As well as the native species, the island is also home to numerous exotic bird species including Californian quail and ring-necked pheasants.

Seabirds - Grey faced petrel

Seabirds form an important part of island ecosystems and FOMLI is currently part way through a long-term project to try and re-introduce grey faced petrel or “oi” back to the island. Due to predation from introduced pests on the mainland, these birds are now only found on isolated headlands and offshore islands such as the Hen and Chicks.  The oi lay a single egg in a burrow and have a long incubation period.  Once chicks fledge they head out to the open ocean to the South Pacific and the Tasman sea and do not return to breed for five years. When they reach breeding age they home back to the site from which they fledged. To establish a new colony you therefore need to translocate the birds as chicks prior to fledging, which is still a relatively new technique with no guarantees of birds successfully imprinting on the new site. FOMLI has undertaken 7 translocations from 2004 - 2015, raising chicks in artificial burrows on the island and hand-feeding them until they fledged. The project saw 226 petrels successfully fledge.  In May 2010 the first of these fledged chicks returned, with several more individuals identified at the site since. No breeding has yet occurred but it is hoped that this might happen in the near future.

Lizards

New Zealand has a surprisingly unique and diverse lizard fauna with over 100 different species.  However, they are an increasingly rare sight on the mainland, due to habitat loss and predation, and many New Zealanders are not even aware of their existence. Fortunately islands like Matakohe now provide a refuge for some of these species. To date seven species have been reintroduced to the island to join the one species, copper skink, that survived on the island after it was deforested. Shore skink, a coastal species and avid sun baskers, were introduced from Mimiwhangata in 2007. This was followed by the secretive and nocturnal ornate skink in 2008, which were released into forest habitat. Moko skink, common gecko and pacific gecko were then introduced in 2010. Moko skink prefer open grassland habitats while Pacific gecko and common gecko are nocturnal species that use coastal scrub habitats and cliffs. The nocturnal forest gecko, which as their name suggests are a forest inhabitant, were released in 2011.  The following year the diurnal green gecko, which prefer scrub habitat were released. A further translocation of ‘egg-laying skink’, is planned for the near future.

Ornate skink Pacific gecko


Invertebrates

Being free from rodent predators, the island is bursting with ‘creepy crawlies’ of all kinds. FOMLI has re-introduced stick insects, and tree weta which are doing particularly well and have spread all over the island.  Giant centipede survived on the island in low numbers and are now increasingly common. In the future there are plans to introduce more invertebrates to create a complete ecosystem such as carnivorous snails, ground dwelling beetles that cycle nutrients on the forest floor, and large endemic herbivores such as weevils. 

The exotic Argentine ant is one insect that is definitely not wanted on the island. Annual surveys are carried out to check for these ants and pot plants are quarantined and treated before transport to the island. Read more.