Its marshy waters are home to dozens of threatened species of bird, including the prized kōtuku, but New Zealand’s largest unmodified wetland is on fragile ground
Sunrise over the Ōkārito Lagoon. It is an ancient and pristine landscape, stretching 3,200 hectares across estuary waters and brackish inlets, home to over 70 species of birds, many threatened.
On a flat-bottomed boat Paula Sheridan and Swade Finch, owners of Ōkārito Eco Boat tours, slide through watery channels shrouded by rainforest beneath the rumpled outline of Aoraki Mt Cook and Mt Tasman. A lone kōtuku gazes through its reflection in search of food, one of a resident population of about eight-10 that stay here year round.
“They are stunning birds,” says Sheridan. “There’s only about 180 in the country – this one we affectionately call Hieronius. This is such a good example of how birds thrive in places like this. The tidal flats here are really rich in food, that is what attracts them. There’s just not so many of them left. After a time you do feel a sense of responsibility towards it.”
Ōkarito Lagoon, just north of Franz Josef on the West Coast, is the country’s largest unmodified wetland. Over a single hour Sheridan points to a large flock of tarāpuka black-billed gulls (the most threatened gull species in the world), royal spoonbills, Caspian terns, oystercatchers, cormorants and tara iti, white-fronted or fairy terns. Tūturiwhatu, banded dotterels, the smallest wading bird on the Lagoon, skitter across the shore line.
But the pristine state is as much to do with geographic remoteness and community perseverance as it is legal protection.
Although we have already lost 90 percent of our wetlands since European settlement, and even though the Lagoon borders on the Te Wāhipounamu South West New Zealand World Heritage Area and the Westland Tai Poutini National Park, the water itself is not protected under the Ramsar Convention on Wetlands, an intergovernmental treaty for the conservation and wise use of wetlands of international importance to which New Zealand is a signatory party.
Such recognition would still allow duck shooting, fishing and shellfish-collecting but local proposals to have the Lagoon included on the “Ramsar List” – the last one in 2017 – seem to fall into the too-hard basket for the small community, population 30.
“Is there a diversity of opinion about the protection of this water?” asks Frank Film producer Gerard Smyth.
Retired forestry scientist and local trapper Ian James agrees Ōkārito Lagoon is of national park quality but says the community has worked with local Ngāi Tahu to make the area a mātaitai reserve. Mātaitai reserves recognise and provide for traditional fishing through local management. They allow customary and recreational fishing but usually don’t allow commercial fishing.
“That protects the land and waterways for the environment and the people, and no commercial activity is involved,” says James. “It works very well. The flounder fishery is in good health, the shellfish are in good health. If one of the fisheries was being over-exploited we can put a rāhui on that fishery to allow it to recover.”
James is also working to bring down the number of introduced pests plaguing the region. For seven years he has been trapping rats, stoats and possums.
“It has certainly helped keep bird numbers up – no question. I’ve been getting 80-95 per cent of the pests with the traps, but until we get ZIP here there will still be a few left behind.”
ZIP – Zero Invasive Predators – is the government-run programme initiated in 2019 in partnership with the Next Foundation to permanently remove possums, rats and stoats from large mainland areas of New Zealand, in keeping with Predator Free 2050 goals. The programme was successfully launched in the Perth River Valley, a 12,000 hectare wilderness area inland from the Lagoon, using “boots on the ground” labour alongside innovative trapping, baiting and detection techniques.
This year, through Predator Free South Westland, it is embarking on an ambitious plan to rid about 110,000 hectares of predators.
“We hope to eliminate every rat, every stoat and every possum,” says James. “I am confident they will get there – they have the resources and the people but it is not going to be easy.”
The Lagoon, and its remarkable wildlife, needs all the help it can get.
“I want to think it is always going to be this way,” says Sheridan, “but sometimes you have to do a little bit of work to make sure that it is. We have to think ahead and not take anything for granted”.
“We can look after it,” says Finch. “It’ll be here so others will get to enjoy it. We just have to put the time and the effort and the energy in.”