The wetland at Nick's Head Station at Muriwai, south of Gisborne, is a world-leading example of positive human interactions with the land, and of what vision and money can achieve.

General manager Kim Dodgshun has worked at Nick's Head Station since 1994, eight years before the current owners bought the property. "They inherited me and we've worked well as a team ever since," Kim says.

When Kim arrived, the land that is now the main wetland was being grazed with livestock roaming all over, and with cows wandering along the beach. "It was nothing like it is today."

Early on, Kim had the idea of creating a bird reserve on the property and ran it past wildlife ecologist and former Wildlife Service ranger Sandy Bull.

The plan, however, hit a snag when the owners at the time said they did not wish to proceed with something that would not produce financial returns.

Undeterred, in 1995 Kim managed to obtain a $15,000 Natural Heritage Fund grant from the local district council and, with Sandy's help, starting trapping. "We caught a big polecat down on the beach," Kim says.

They also put up "No shooting" signs – it had been a popular duck shooting site, fenced off 15 hectares and planted flax around the outside. The birds flocked in, bringing seeds from other wetlands in the area and the plants began to grow.

The story of the wetland took another turn in 2003 when the farm changed hands after the Overseas Investment Commission approved an application from a US billionaire to buy the land, in what turned out to be a 12-month-long process.

He had first visited the farm in 2002 and embraced Kim's plans to create a wildlife reserve.

The final step for the sale was to gain iwi approval. Kim says communication was the key and once the iwi knew what the owner planned to do with the property, the deal was  approved.

In response to Kim's plans, the owner said, "Let's make this bigger and better", and brought out renowned landscape architect Thomas Woltz from the US to design the wetland, with advice from Kim and Sandy.

A previous manager who had farmed there for 35 years had set in place the foundations to drain the saltwater from the low lying areas. He put up a netting fence on the beach which collected all the driftwood and storm debris, building a natural wall with sand.

Next, he added another fence on top of that and planted it out with marran grass and other plants.

Later, in the 1960s, a drain was put in to get rid of the remaining saltwater but a narrow, shallow channel remained, with 700 acres of catchment running into it. In summer it dried up. The surrounding paddocks were all very wet with no drainage.

Kim had already planted some native blocks but as Thomas Woltz learnt more about New Zealand and its trees, "the master plan was to revert the land back to how it was 700 or 800 years ago, with a profitable farming operation, back when there were no predators and the land was covered in native trees", Kim says.

Planting began in earnest in 2003 and now there's almost 700,000 natives on the property – coastal varieties with "the big fellas" – rimu, matai and totara – planted among them.

The wetland project began in 2005 – plans were drawn up, the land was surveyed and work began, initially with six diggers.

Kim had warned the contractors that trucks with wheels and 20-tonne diggers wouldn't work in the boggy terrain, but they brought them in anyway and all of them got stuck.

Which left the six smaller diggers. Firstly, a wall was put in to stop the saltwater coming in over the original wall at the beach. "We put in some more small ponds up the valley and worked our way west."

Deep channels – "about 2½-cars deep" – were dug out to ensure the wetland had water year-round.

The material excavated from the channels was made up of a layer of Plasticine-like blue tacky soil sandwiched between shells and "rubbishy" soil. The blue material was used to seal the walls or build the islands, while the "rubbishy" soil helped shape them.

Diggers scraped up the topsoil which was carted on to the shaped islands by trucks with tracks to prepare them for planting.

However, when they came to seal the western side of the wetland, they ran out of the blue soil so plastic liner had to be used in some sections.

"We pegged out all the walls and had three diggers in a row, one digging the holes, another with a big roll of the plastic, working at snail pace, unrolling it, with a third quickly filling it in before the walls collapsed," Kim says. Thankfully, it worked.

"Once it was all done, we had to pump all the water out. "We got council permission to pump it out into the sea over sheets of corrugated iron to protect the beach."

In the process, they found some old kahikatea, big, old stumps of trees, leading them to believe that, pre-settlement, it must have been an old kahikatea swamp.

"There are some stumps on the beach visible at low tide that have been dated at more than 8000 years old," Kim says.

As well as dealing with the challenges presented by the terrain, during planting, they encountered another problem.

Holes were dug with an augur, and some crystal rain put in with soil over the top before the tree was planted with a fertiliser capsule.

Later they went back to one of the islands to put in stakes to mark where the native plants were but found that most of them had been pulled out.

"All the rats were just pulling them out and eating the fertiliser caps. They were having a ball."

The answer was to use about 100 bait stations with Pestoff rat bait, from Farmlands, and "there were bucketloads of rats coming in," Kim says. It's slowed down now.

"That was just another little challenge. I can't believe how well the plants have grown."

Now the islands are all finished and planted with native trees – 10,000 trees to the hectare. On the hills, it's 2500 to the hectare.

The wetland has two 1ha islands and several smaller ones. All the islands are in place of valleys, which was Thomas Woltz's plan, imagining erosion coming down and islands forming.

At its peak, 25 people were working on the project. The labour was all local and all the trees were sourced from the Muriwai area. "Now the locals come to get our native trees," Kim says.

The farm is 3300 acres in total with nine kilometres of coastline. It runs Angus cattle, 285 breeding cows and 3300 sheep. This is likely to be reduced to 3200, with the aim of getting more out of fewer stock, by doing things better, "by selling them when they are ready to go and when the market is ready to take them".

"We are looking at the possibility of going down the regenerative farming path, though the steep contours of Nick's Head Station add to the challenge – more investigations in this area are required."

Facial eczema is a problem so the farm focuses on sourcing facial eczema-resistant stock. The farm uses dicalcic phosphate fertiliser, not straight superphosphate, and nitrogen, which was seldom used, has not been used for about eight years.

The station employs a staff of 16, who look after conservation, including a former DOC worker who does trapping and twice-weekly night shoots by bike, general hands, stockmen, groundsmen, a secretary, a citrus manager and assistant, who have 50 hectares of citrus to tend, plus contractors.

Kim pauses, distracted by something that needs fixing. "Everything we do on this place, we got to maintain it.

"We've got this magic place that we've all had something to do with and created what it is today. We can't let it go back. We can't let wild pine trees start growing.

"We've got convolvulus – we've got to keep taking it out – we've got kikuyu grass on the farm that we have been spraying, we have got to keep at it. "

"The old place never sleeps."

• The bus trip to Nick's Head Station was organised by Kees and Kay Weytmans, who provided delicious, nutritious packed lunches. Kees' efforts to make sure everyone was comfortable during the talks on the jetty by providing lucerne bales to sit on were also much appreciated.
• For more on Nick's Head Station, watch Thomas Woltz's Ted Talk at www.youtube.com/

watch?v=9VlY-3V63yI.