• Macquarie Island Wildlife Sanctuary
• Wildlife On Macquarie Island

After decades of being overrun with feral rabbits, World Heritage-listed Macquarie Island is on its way to returning to the wildlife haven it once was. At Sandy Bay on the east coast, royal penguin colonies are coming down from the steep hillsides, with groups of breeding pairs waddling down a well-worn track to the ocean. Macquarie Island Nature Reserve: a philosophical approach to ecosystem conservation and the management of human impact By Leslie Houghton Stephenson and Parks and Wildlife.Macquarie Island Nature Reserve: draft manag Tasmania.Dept. WHYY The Pulse features Island Conservation's Director of Science, Dr. Nick Holmes, in a story about unintended consequences as he explains the introduction and removal of invasive species on Macquarie Island. Maiken Scott (Host): When humans discover a new place they sometimes end up changing what was there in dramatic ways. That happened on Macquarie Island. It’s a tiny, remote spec of.

PIP COURTNEY, PRESENTER: It was one of the most ambitious pest eradication projects in the world: to rid a sub-Antarctic island of rabbits, rats and mice. Seven years and $25 million later, Macquarie Island has been declared pest-free. But the celebrations are tempered, with the discovery of a new environmental threat, as Fiona Breen reports.

FIONA BREEN, REPORTER: It's a long and lonely haul across the icy Southern Ocean from Macquarie Island to Hobart. These sub-Antarctic expeditioners can't wait to get off the ship and head home.

NANCYE WILLIAMS, DOG HANDLER: I'm excited, nervous. It was a long trip up the Derwent and I'm looking forward to seeing mum and my dog on the other side of the gate.

FIONA BREEN: Nancye Williams has spent much of the past four years on remote Macquarie Island, halfway between Tasmania and the Antarctic wilderness. She's walked its length and breadth, with workmates Rico the labrador and Katie the springer spaniel. Part of a massive $25 million pest eradication scheme, they've been hunting for rabbits. Now they're in Hobart, it's time for some rewards.

With an incredible array of wildlife, Macquarie Island (or Macca) is a World Heritage Site and a wonderful spot to visit as part of an Antarctic cruise. In particular, cruises that visit Macquarie Island visit the colonies of King, Gentoo and Southern Rockhopper Penguins.

NANCYE WILLIAMS: Still going to go rabbit hunting. Tomorrow morning is the first thing. And, um, yeah ...

FIONA BREEN: Aren't you sick of hunting?

NANCYE WILLIAMS: No. There hasn't been any rabbits ... (Laughs) ... for the last 2.5 years, so they're looking forward to it and I am as well. They've only had frozen rabbits out of the freezer, so they'll be looking forward to the real thing instead.

FIONA BREEN: Rabbits, rats and mice are a legacy of a long line of visitors to Macquarie Island that goes back to sealers in the early 1800s. The rabbits were deliberately introduced as a fresh food source. The rest were escapees from whaling ships. Over 150 years, they thrived. Rabbits browsed on the vegetation and undermined the hillsides with their burrowing. Rats and mice raided seabird nests and ate native plant seeds.

???: As human beings, we stuffed this up, and now, as human beings, we're fixing it up, which is really good. And to be a part of that, is really neat.

FIONA BREEN: After years of work, things are now turning around.

KEITH SPRINGER, ERADICATION MANAGER: It's really a huge satisfaction that all the people that worked on this project and worked to make it happen have sort of pulled it off. So, yeah, that's an incredible feeling and I suppose, because I've had the good fortune to be on the island recently and see the recovery of vegetation, that's a real reward as well.

FIONA BREEN: For eradication team manager Keith Springer, it's vindication. He's had to navigate through the ups and downs.

KEITH SPRINGER: Nobody had tackled an island the size of Macquarie before to get rid of rabbits - rabbits and mice in particular, so there was a lot of doubters that it could be done. And I think there was - there's maybe a low level of awareness of eradication methodology.

Macquarie Island Wildlife Sanctuary

FIONA BREEN: Early on, tonnes of baits dropped on the island by helicopter killed most of the rabbits, rats and mice. Although the aerial baiting was conducted during a time when there were fewer native species on the island, 2,000 rare and endangered seabirds were also poisoned. It fuelled a campaign to withdraw the program's funding.

Wildlife On Macquarie Island

KEITH SPRINGER (April, 2011): The deaths of some birds in this case can be expected, so it's a reality that we needed to accept early on. We have long-term goals for the project, and so in 50 years' time, for example, and onwards, would the benefits to those species have accrued to the point that the mortality in the first instance is outweighed?

FIONA BREEN: The ABC has followed the eradication program from the start. A year into it, the dogs and their handlers had caught the last 13 rabbits, although they didn't know it at the time. Nancye and her dogs were responsible for two of those last rabbits.

NANCYE WILLIAMS (April, 2012): Katie and Finn detected where it was, in a rock stack. Set some traps and got that rabbit successfully and it was fantastic for the dogs to finally have a fresh rabbit as well, not something that's been pulled out of a freezer. And the second one was down at Petrel Peak. Katie came across that sign: one rabbit dropping in a bird's nest on top of a hill.

FIONA BREEN: By 2012, when Landline returned to Macquarie Island, there were already signs of success.

(April, 2012) Here at Green Gorge, about halfway down Macquarie Island, there's a remarkable transformation taking place. Hillsides once devastated by burrowing rabbits are slowly coming back to life. You can see healthy young shoots springing up under the tall tussock grass. Leafy megaherbs and the endemic Macquarie Island cabbage are thriving. Their leaves, normally nibbled to the stems by rabbits, are perfectly formed.

On a hike 16 kilometres across the island from Green Gorge to the main station, there were emerging signs of new life.

DANA BERGSTROM, ECOLOGIST (April, 2012): It's an entire ecosystem in response. And one of the things that's really exciting is that we're seeing gossamer slopes covered in spider webs and that's something I've never seen in the last 20 or 30 years that I've been coming to the island. A lot of the invertebrates, the native invertebrates, are coming back in bounds.

FIONA BREEN: In 2012, however, the island hunters knew that some of their hardest work was before them. They'd not seen a rabbit for months, and yet, they couldn't be sure they'd got them all.

KEITH SPRINGER (April, 2012): The job just gets much, much harder when there's so few. So the team of about 15 hunters with the dogs have been looking for several months now and they haven't found any fresh sign of a rabbit, so that's an indication of the level of effort that's going in and not yet finding signs of those very small numbers of remaining bunnies.

FIONA BREEN: Now, two years later, they've finished the job. The hunters say they've searched every nook and cranny they could access with their dogs and found nothing. Over the entire campaign, they clocked up 92,000 kilometres on the GPS.

Are you positive there's no more rabbits or mice or rats down there?

KEITH SPRINGER: I'm as positive as I can be, given that the hunting teams carry GPSs. We log all their travel and we plot it on a map of the island and it's been covered so thoroughly that if there was a rabbit there that was eating something or digging or leaving prints in snow or mud, I'm confident we would've found it.

FIONA BREEN: Steve Austin has trained dogs for more than two decades, including police, quarantine and search and rescue dogs.

STEVE AUSTIN, DOG TRAINER: You see this happening and you know that if they hit the water, they're gone.

FIONA BREEN: The Macquarie Island project was his biggest challenge.

STEVE AUSTIN: This has taken a lot of dogs to get here. I mean, what you see now is the end result of probably 40 or 50 or 60 dogs. These dogs are the cream of the crop.

FIONA BREEN: In the early days, everyone was watching. There was scepticism amongst scientists and workers on the island about having dogs in a World Heritage area.

STEVE AUSTIN: At Macquarie, it was not only just finding the rabbit odour, but ignoring all the other stuff and ignoring the elephant seal and the fur seal and the penguins - that was the most difficult part of their training. No kills, no injuries on native animals. A wonderful result.

FIONA BREEN: Today, Steve Austin is in Hobart to catch up with the eradication team. It's time to assess his former pupils, see how they've fared in the rugged and wet terrain. He's taking them through their paces.

STEVE AUSTIN: I think they look fantastic. I mean, we might have a health resort for springer spaniels down there. He looks in great shape.

FIONA BREEN: It's a bittersweet time for the handlers as they watch Steve Austin with the dogs. His assessment will determine the dogs' future. Some will work in quarantine, others will end up in Tasmania's invasive species unit. One is heading to Chile for another pest eradication project.

KEITH SPRINGER: A bit of a change of scenery for Finn, who's going there, and Finn's handler, Karen, is going to work on that job as well with Finn.

FIONA BREEN: For the handlers, the day is nearing when they'll have to say goodbye to these companions. They've been working with them nearly seven days a week on Macquarie Island and it's going to be tough.

NANCYE WILLIAMS: Definitely an emotional time, um, knowing that at the end of it you have to hand them back and not see them again. It's pretty full-on.

FIONA BREEN: How you going to do it?

NANCYE WILLIAMS: I don't know. I think I just have to hand over the lead and walk away.

FIONA BREEN: Now the pest eradication team has left Macquarie, its population has dropped from 30 to 16. The World Heritage-listed spot will continue to be a research base for Australia's Antarctic Division and Tasmania's Parks and Wildlife. Macquarie Island's problems, however, are not over. Scientists have uncovered another environmental disaster.

JENNIE WHINAM, ECOLOGIST TAS. PARKS AND WILDLIFE: Massive areas of vegetation across the plateau are dying and then they erode out and then they're blown away and so we're actually getting instability in the higher parts of the plateau as well as losing the major keystone species for Macquarie Island's plateau vegetation.

FIONA BREEN: Ecologist Jennie Whinam has worked on Macquarie regularly for the past 30 years. About five years ago, she noticed patches of vegetation dying on the island's high plateau. It was the start of a rapid decline for the endemic cushion plant known as azorella.

JENNIE WHINAM: We know that it's probably related to a combination of effects, likely to be things like changes in the patterns of weather. Everybody who's been going for a long time has noticed longer drier periods, changes in the wind direction. However, we have isolated a few pathogens from the plants, but we don't know if these are actually the cause, the primary cause of the dieback, or whether they're secondary.

FIONA BREEN: Azorella covers 90 per cent of the plateau, which is in itself a huge part of the land mass of Macquarie Island. While rabbits did nibble on these plants, scientists say the dieback continued even after the rabbits were gone.

JENNIE WHINAM: It is a keystone species, important for a whole lot of other plant and invertebrate species, and so losing azorella in such a large extent is quite a significant blow for the island at a time when most of the other vegetation is recovering.

FIONA BREEN: In a desperate effort to save the now critically endangered plant, scientists have set up an orchard on the north end of the island. They've had some success. The first seeds have been produced. At the rate the entire upper plateau is dying, they could end up being the last azorella plants on the island.

At least for now, one battle is over; these dogs and their trainer have done their job. Their legacy will live on on Macquarie Island.

STEVE AUSTIN: We've got it pest-free, rabbit-free and that now will go back to its original state, which is a World Heritage area and these guys were part of making that successful. To see 'em now come back so healthy and happy and be a part of that great result, it's just the highlight of my career - by far, by far.

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