Waikawa haven for tūturuatu

A pair of tūturuatu/ shore plover out patrolling their territory. Picture by Jack Ward

by Jack Ward

Surviving on Waikawa (Portland) Island is not for the faint-hearted, especially for a tiny bird.

Always under the watch of nearby Māhia Peninsula and Rocket Lab, the island is only a kilometre from the mainland yet the sense of disconnection from the world is apparent from the moment the helicopter lands.

Tawapata South Incorporated, descendants of the original settlers,  own the island.  Onenui Station on the Māhia Peninsula runs some sheep there.

It is home to more than a third of the world’s population of tūturuatu or shore plover.

The birds were first introduced to the island in 1999.

Helen Jonas, biodiversity ranger for the Department of Conservation (DoC) has been involved with the birds’ recovery for 12 years.

“I enjoy working with the birds — I mean, look, this is my office,” Ms Jonas says as we walk along the shore on the lookout for pairs of the plucky plover.

“I have always wanted to work in the bush since day dot when my dad took me tramping.”

It is the mating season, until February,  for the shore plover.

The pairs are very territorial, alerting their mate to intruders with a trill-like chirp.

“Some mate for life, and others move around like people do,” chuckles Ms Jonas.

Predation on the island is rare but when it happens, it leaves the local population in tatters.

In 2012, a single predator savaged the population from 80 to only 10 individuals.

The purpose of this two-day trip to Waikawa is for biosecurity, detection and a Darwin ant survey.

Darwin ants, native to Australia and fond of ports have been discovered on the island, although it is not clear how the ants arrived.

One of five ant species on the island, the Darwin ant identification is the smell it emits when threatened.

Their defence mechanism is a potent pheromone — an ammonia smell that stings the nostrils.

On an earlier trip this year, 1200 bait stations and 82 tubes were laid in a fenced-off area in one-metre grids along the northern tip of the island to eradicate the Darwin ants.

The fenced area covered 16,454sqm and the results showed ant activity in only 11 of the 1200 bait stations after leaving the bait out for a day.

“We want to see how many ants were killed last trip and remove them from the northern spit of the island,” Ms Jonas says.

Coloured stakes were laid at 20-metre intervals along the spit with either blue, pink or silver colourings and bait lines with Fipronil bait to attract the ants.

The bait lines were set on the first afternoon on the island and revisited the next afternoon.

Next morning conservation stalwart Hans Rook took us on a trek around the island to check and clean 80 instant kill traps.

Mr Rook has over 50 years of conservation knowledge having worked for the-then Wildlife Service and its successor DoC from 1972  until 2014. He started as a 17-year-old.

“It was never a job for me, but a 42-year holiday,” he says.

Mr Rook, known as Rooky, has retired but he still volunteers.

“Conservation is a hobby and a religion,” he says.

“I have worked on some incredible islands that you may go to once and then never again — just absolute magic.”

He worked with the late Don Merton in the 1970s on Big Mangere Island in the Chatham Islands to bring the black robin population back from near extinction, and with kākāpō in the Milford catchment.

Rooky is meticulous as he cleans the traps after  decades of experience on the conservation front-line. He is like a palaeontologist carefully brushing around a fossil.

“I brush the sides, check for snails wedged under the trap trigger plates, clean the steel trap and replace the egg.”

Snails have developed tough shells to survive in their coastal environment.

By getting under the traps, they can compromise them and a predator can potentially slip through without setting off the trap.

The use of eggs is a visual lure for predators such as rats.

It is a natural food source and the eggy smell permeates through the shell.

“The traps need to function at 100 percent here as they are on the combat edge for when a predator ends up here, and all the hard work is lost.

“These traps are an instant kill and the number one defence.”

Rooky is quick to acknowledge Ms Jonas and her work ethic.

“I admire Helen’s commitment and dedication because, without that, it does not work — you have got to have that drive and that girl does not have a lazy bone in her body.

“You need that long-term commitment because you do not get knowledge in five minutes.

“I can contribute by helping to do the mundane things like trap maintenance while Helen can focus on the birds.

“All I want is something done right. All I wish for is that all these traps are always fully operational.”

Our journey across the island takes in more remote traps marked by colourful buoys.

We walk past a dead fur seal pup and a sunbathing seal in the space of 15 minutes. The battle for survival is everywhere.

Rooky said the rise in population for the fur seals created competition for food and there were always winners and losers.

“It is survival of the fittest. The mother will separate from the pup after a year when she becomes fertile again and heads to the breeding grounds and the pup has to fend for itself.”

Returning from our trek, we ready ourselves, with the help of kai for the afternoon for the ant survey.

The survey yields only two pottles of ants, from outside the area which is closest to the woolshed before the fenced area.

It is a success and proof that the poison operation is working.

“All the pottles in the poison zone were empty — the operation was amazing,” says Ms Jonas.

The battle is not over though.

“We still need to do the southwestern side of the island and utilise technology with a device to put out the bait in small enough quantities at regular intervals on the cliffs so they stick to the surface.”

The Fipronil poison is the same as the one used for Argentine ants.

“There is nothing available for a natural chemical on the scale we need for the ants.”

That evening we observe an evening show by the white-faced storm petrel otherwise known as the Jesus bird as they take to the night sky to find their burrows.

Attracted by our lights, they make a beeline for us and we have a few close calls, feeling the down drafts from their flapping wings.

It is the final morning of the trip and we accompany Helen to see some of the tūturuatu pairs.

The ants are unwanted guests here.

“We do not know the full extent of damage by the ants but there is some,” Ms Jonas says.

“We have to get rid of the ants to protect the chicks.

“The ants gang up on the chicks when they are vulnerable and the parents cannot do anything.”

Exploring south of the jetty is the area Ms Jonas calls the Fendalton of Waikawa.

It is a highly desirable property for the tūturuatu pairs along the shore by the sea.

Walking along, we are greeted by their trills at our encroachment on their territory but they are not scared off, which is their Achilles heel.

“The shore plovers think they are bully boys.

“Earlier this year we had stoat dogs on the island checking on biosecurity and the shore plovers came straight up to them.”

The final count of 36 mating pairs is an increase from the 33 pairs last year as young shore plovers come into the breeding circle.

This is a result of translocation with chicks from the Chatham Islands where they are endemic.

“It introduces new blood to the island and by mixing the genetic code, it makes the species more robust.”

Ms Jonas says it takes a year before distinct features start to emerge, indicating the gender of the tūturuatu/ shore plover. “The males have a black mask and the beak is a defined line between the black and orange colouration.

“The females have a smudgy lighter mask and the colour transition is smudgy. In the bird world, the boys always look the best.”

The warmer months mean the visits to Waikawa involve check-listing biodiversity and traps to take action if there is a predator on the island.

Leaving the island behind, all signs are positive for the shore plover.

“They are in great nick, if there continue to be no predators.”