Liferaft for tūturuatu

Shore plovers are one of the world’s rarest shorebirds and need a huge helping hand to survive. By Peter Lo and Helen Jonas. Images Peter Lo.

Forest & Bird magazine

A version of this story was first published in the Summer 2023 issue of Forest & Bird magazine.

Aotearoa has more than its share of critically endangered species, and tūturuatu shore plover is one of the less well-known members of this group, despite it being a colourful and attractive bird. Perhaps it’s because they have been extinct on the mainland for about 150 years. 

Shore plover are endemic to New Zealand, but with a total population currently hovering around 250 birds they are in imminent danger of disappearing forever. 

These engaging little birds were once found around much of New Zealand’s coastline, but by about 1880 they were confined to a single location in Rēkohu, the Chatham Islands. 

The Department of Conservation initiated a translocation programme nearly 30 years ago to reduce the risk of shore plover becoming extinct. 

Captive-bred juveniles were released on four predator-free islands, with mixed results, while Mangere Island, in Rēkohu, was repopulated by wild juveniles from neighbouring Rangitira. 

Today, tūturuatu are restricted to Mangere, Rangitira, Motutapu, and Waikawa Islands. Translocations to Motuora and Mana Islands eventually failed.

Tūturuatu were first translocated to Waikawa, also known as Portland Island, in 1999. The tiny windswept island, which lies 1.3km off the end of Mahia Peninsula, has a rich history of being home to Māori for 600 years. We have been looking after shore plover on Waikawa, in the Hawke’s Bay, for many years, with the support of the owners, mana whenua, DOC staffers, and local community, including Rocket Lab staff. 

The island is home to the largest number of shore plover outside Rēkohu, as well as tuturiwhatu New Zealand dotterels, tōrea oystercatchers, tītī petrels, migratory birds, and kekeno seals. 

Tūturuatu feed on tidal rock platforms, where they glean invertebrates from the shallows. On Waikawa, they also make use of the sandy beaches. Although quite large, at approximately 140ha, only the northern tip has suitable breeding areas. 

Volunteers Kay Clapperton, Paul Dunford, Jim Walker and Helen Jonas.

From 1999, numbers increased steadily to around 80 birds, including 37 breeding pairs. However, in 2012, the population suddenly crashed and fell to as low as 10 birds, with four pairs. 

After extensive trapping and poisoning, the efforts of a trained dog eventually revealed the culprit was a rat. The rodent was never found, but the dog located a rat nest with scats. 

It was possibly a single individual that caused so much havoc. Subsequent tracking and searches with dogs found no further traces of a rat. 

Since 2014, the tūturuatu population has almost recovered to its pre-rat strength, with some assistance from translocated birds.

Volunteer Kay Clapperton surveys prime shore plover habitat on Waikawa Portland Island, with Mahia Peninsula in background.

Darwin ant incursion

The tūturuatu population on Waikawa Island now faces a new threat. In 2010, an aggressive invasive pest, Darwin ant, was discovered. This voracious forager outcompetes and displaces native ants and will swarm and kill newly hatched chicks. By 2014, the killer ants occupied most of the birds’ nesting area on the northern half of the sandspit. 

The solution to Darwin ants is to apply poison baits to eradicate them from the spit. Baits are laid among the grass and rushes, and along the beach above high tide. Part of the sandspit is temporarily fenced to keep sheep out, and within this area the gel-like bait can be applied to the ground using cartridges and caulking guns. It is not practical to fence off the beach, so here baits must be enclosed inside pottles to prevent sheep encountering them. 

Each baiting operation is a logistical planning challenge, particularly in the post-Covid environment. Firstly, the weather gods need to co-operate to allow boat and/or helicopter transport to and from the island. A small team lands on the island several days before the main baiting event to prepare and lay out bait-filled pottles on the beach. 

On the main baiting day itself, 24 people work in two groups of 12. The bait does not stay attractive for long, so it needs to be put out quickly. A second team stays behind for a few days to retrieve and clean up the pottles and to check tracking tunnels for any sign of rats. 

Results from the latest survey in October 2023 were encouraging. No Darwin ants were found within the poisoned area, but a two-year gap in baiting has allowed them to extend their range southwards on one side of the spit. A small mopping-up operation will be needed to achieve eradication. What does the future hold for these plucky birds? Tūturuatu will thrive on their Waikawa liferaft, so long as they continue to get help to repel the occasional marauder that tries to come aboard. 

The island’s rare combination of suitable habitat and being free from mammalian predators (except mice) is what allows tūturuatu to prosper here. But Waikawa is close to the mainland, so constant vigilance is needed against further pest incursions to protect this special place and its endangered treasures. 

We thank the shareholders of Tawapata South Inc for their continued direction and access to their whenua to care for the taonga of Waikawa. 

Many Department of Conservation staff, volunteers, and Rocket Lab personnel have also participated in this project over many years. The expertise of DOC scientists Dr Chris Green (since retired) and Murray Fea, helicopter pilots, boat skippers, and contractors is gratefully acknowledged. 

DOC staff and volunteers apply baits for Darwin ants.

Helen Jonas is a Department of Conservation officer and the project leader for tūturuatu management on Waikawa Island. Since 2013, Peter Lo has made six trips to Waikawa as a volunteer, and one to Rangatira.

Tūturuatu are delightful characters with an engaging personality. They hold territories when nesting and will approach intruders and greet them with a characteristic head bob as if to say “and who are you?” Although this habit is endearing for bird lovers, it leaves tūturuatu poorly adapted to cope with mammalian predators. 

Furthermore, unusually for a shorebird, they nest under the cover of short coastal vegetation or among driftwood and rocks, which makes them especially vulnerable to introduced predators, including mustelids and feral cats. Other reasons for their decline include habitat loss, disease, predation by gulls and hawks, and being attacked by dogs. 

The male shore plover has a black face, and the beak is mostly red.