Giant weta find new pest-free home

WETA RELEASE: DOC scientific advisor Chris Green, far left, speaks to a crowd about the wetapunga release.
WETA RELEASE: DOC scientific advisor Chris Green, far left, speaks to a crowd about the wetapunga release.

They are arguably New Zealand's ugliest creatures with maori even naming them "God of ugly things", but 25 giant wetapunga were the centre of attention for an adoring crowd yesterday as they were released onto pest-free Tiritiri Matangi Island off the Whangaparoa Peninsula.

Not only are they our largest insect, wetapunga are one of the heaviest insects in the world.

"These are big insects. An adult female body can measure 10cm long and with its legs it covers your whole hand," says Department of Conservation scientific adviser Dr Chris Green.

WETAPUNGA: Twenty-five of these endearingly ugly creatures were released on Tiritiri Matangi Island on Saturday in an effort to ensure their survival.
WETAPUNGA: Twenty-five of these endearingly ugly creatures were released on Tiritiri Matangi Island on Saturday in an effort to ensure their survival.

Weighing in at 35 grams, adult females are can heavier than a house sparrow. Some female wetapunga can weigh as much as 50g.

But looks can be deceiving.

"Despite their size and fearsome appearance wetapunga are quite docile," says Green.

They are also threatened.

A tasty morsel for introduced pests like rats and stoats, the insects soon disappeared from the Northland and Auckland mainland as well as almost all the Hauraki Gulf Islands. Hauturu/Little Barrier has been it's last refuge.

While there were small kiore rats on the island which kept numbers down, they hadn't decimated the weta population as the bigger rats on the mainland had. The island was cleared of rats completely in 2004.

"Making Hauturu pest-free by eradicating kiore rats ensured wetapunga were able to survive on the island.

"We've seen wetapunga double in numbers on Little Barrier since we removed the rats. But it's very risky having the entire population of a species in one location."

"To protect wetapunga from the risk of extinction we've taken adults from Little Barrier and successfully bred them in captivity. We're now moving captive bred wetapunga to new pest-free island homes," says Green.

The 25 wetapunga were bred at zoological attraction Butterfly Creek near Auckland International Airport. They were bred from 18 adult wetapunga captured on Little Barrier Island in December 2008 and May 2009. 

In September last year 25 younger weta were also released onto Motuora Island off the Mahurangi coast.

More than 100 wetapunga bred at Butterfly Creek are planned to be moved onto each island over the next five years.

In addition 20 wetapunga will be transferred to each island direct from Hauturu to increase the genetic diversity of the two new populations.

"It will take a number of years to build self-sustaining populations of wetapunga on Tiritiri Matangi and Motuora because these giant insects have long life cycles," says Green.

"They're feeding well, eating the leaves of a range of native plants. They're bigger than the wetapunga released on Motuora.

"Some are adults, some are close to adulthood. We hope they'll start mating and laying eggs on Tiritiri Matangi in late summer around March," says Butterfly Creek wetapunga expert Paul Barrett.

The wetapunga are housed in purpose-built facilities at Butterfly Creek with the breeding programme sponsored by Greenfingers Garden Bags Ltd.

Tiritiri Matangi is a sanctuary Island and is managed by community group Supporters of Tiritiri Matangi in a partnership with DOC, just as Motuora Island is jointly-managed by the Motuora Restoration Society.

"The release is a milestone in the restoration of the natural heritage of the island. Having wetapunga on Tiritiri Matangi enhances the island's reputation as a sanctuary for a wide range of our rare and magnificent wildlife close to our biggest city," Supporters of Tiritiri Matangi spokesman Peter Lee says.

Group members and others were out in force on Saturday with 150 hoping to catch a glimpse and snap a shot of the bulky armoured insects.

Being nocturnal the insects couldn't be released into the open during the day as they would likely be lunch for the many birds on the island, says Green.

Instead they were put into bamboo sleeves, up in the canopy where they would venture out during the night.

The Government has come under strong criticism from conservation and biology scientists from universities and institutes around the country recently for their plans to cut 96 jobs over the next six months within the conservation department, aiming at saving $7.5 million.

More than 100 signed a letter of caution to Conservation Minister Kate Wilkinson and DOC director general Al Morrison last week.

Job losses would seriously erode DOC's efforts in conservation management and planning, as many species and ecosystems "teeter on the edge of oblivion", the scientists say.

In the 2009 Budget, DOC had $54m shaved from its budget. Last year $550,000 was saved by centralising corporate office functions, with the loss of 20 jobs.

Although Morrison and Wilkinson have previously said rangers and field based staff would not be affected by the cuts, that claim has been described as "ludicrous" by the scientists.

While some DOC programmes like the kakapo recovery along with others like wetapunga recovery programme has backing from community and business groups, other species might be more vulnerable.

"Other species are not particularly charismatic, or the ecosystems are not particularly accessible. For those, DOC has to be there," signatory Massey University postdoctoral fellow Kevin Parker says.

"Ongoing reduction in capacity, support and funding for New Zealand conservation" was causing concern.

At the release, Ministry of Conservation representative Sean Goddard emphasized that "recent changes are to internal organization restructuring to preserve conservation programmes in the field so they are as efficient as possible".

Programmes like the wetapunga recovery programme would not be affected by the cuts, he says.

Rodney Times