The money is flowing in and the birdlife flowing back ... but it's early days yet.
Nelson Mail reporter Naomi Arnold checks progress on the Brook Waimarama Sanctuary in this great article from The Nelson Mail.
The birds are coming down out of the hills and back into our lives. There's been a skinny brown weka poking around the bushes near the Nelson Post Shop during the last couple of weeks, and others spotted running through the gardens of The Wood.
There are more kereru weighing down city branches, more tui on the flaxes, and more bellbirds in Richmond gardens. In fact, there are more birds around here than there have been for years.
Their increasing numbers are due to the pest-trapping programmes in the hills from Richmond to Delaware Bay, which have been wiping out rats, stoats, possums, and more.
But those behind the Brook Waimarama Sanctuary, an ambitious conservation project at the head of Nelson's Brook Valley, want more.
The old water reserve is already a biological haven, a dense pocket of mature beech, podocarp and broadleaf forest, some of which has never been felled. As trapping, tree-planting, weeding and track works progress in the valley - which includes 17,000 pests killed in fewer than six years and 80km of new tracks cut - it's also become full of new life. Pairs of little green rifleman, each weighing less than a $1 coin, have been spotted raising successful clutches. There are more robins, more falcons, and trappers even report hearing kaka at the tops.
Brook Sanctuary general manager Hudson Dodd says all that is excellent news - but only to a point. "It tells the story of a need for a fence."
The trust behind the sanctuary wants to build a pest-proof fence surrounding the valley, capable of blocking predators, from mice to deer.
Once that's done, they want to step up the pest-killing, and by 2015 they want to stock the area with kiwi, tuatara, kakapo, robin, weka, bats, falcons, insects, and more - even spectacular burrow-nesting seabirds, the guano of which would bring back additional biological richness to the area.
The goal is to have enough birds in the sanctuary to be left alone to grow and breed, so they'll spread further south into the wilderness, including Mt Richmond Conservation Area, and through forested corridors to the gardens of greater Nelson.
It will be the largest sanctuary in the South Island and the second-largest in New Zealand, with a circumference twice the size of, and an area three times bigger than, Wellington's Zealandia (formerly the Karori Wildlife Sanctuary), with much more established forest.
"Karori likes to talk about their project being a 500-year journey," Mr Dodd says. "But we've got a 400-year start on it."
In time, the trust expects the sanctuary will be nationally significant for tourism and conservation of endangered species, and will be the No 1 visitor attraction in Nelson. There has even been talk of establishing a lodge overlooking the protected bush.
It has been well supported so far. Nelson City Council is in the midst of assessing the sanctuary's independent Arrow Strategy business case and feasibility study to determine if ratepayers will support it to the tune of $1m; that's due to be discussed at a council meeting on May 14.
Tasman District Council has pledged $300,000, though both sets of council funding depend on the trust meeting its own targets. Your Lotto ticket may also have helped. In November, the Lotteries Grants Board announced a $500,000 grant to the trust, the board's largest donation in a decade. There's also been a one-off anonymous donation of $250,000, and hundreds of local households who support the scheme as financial members. That's not to mention the 26,000 hours of free labour a year from more than 250 volunteers, and the huge amount of donated goods, such as peanut butter and eggs: some of the top consumables in any self-respecting pest-trapping regime.
Mr Dodd expects the first sod to be turned in November this year. But he won't be making apologies if they don't raise enough money in time. From the start, he says, the project has been aiming to stay out of debt.
"We could have built it years ago by borrowing the funds to do it, but the trust committed to this conservative approach," he says. "We're doing it the old-fashioned way. That takes time."
The trust has been wanting to build this fence since early 2002. It's been so long, in fact, that Mr Dodd acknowledges patience among some sectors of the community is stretching thin.
The global economic crisis forced fundraising to take a backseat for a while, but as the economy recovers, the push is now on again.
They've just launched the last phase of their fundraising campaign, dubbed Save Our Babies - Get Behind the Fence, and have been at the Saturday market for the last month seeking exposure and support.
The trust is looking for people to sponsor fence posts, which cost varying amounts depending on the visibility of the "zone". A post up on the ridge will cost $100; one at the sanctuary entrance is $5000.
But the idea of a pest-proof fence up the Brook doesn't sit well with everyone. The 2009 resource consent decision notes a matter of "major concern" to submitters was the financial viability of the application and its impact on ratepayers for future operating costs.
Its opponents get particularly nervous when they look at Wellington's Zealandia. In a December editorial, The Dominion Post labelled it "an unmitigated failure" as a tourism venture and "a financial black hole" after ratepayers were forced to bail out the struggling sanctuary - even though at the same time, the project was lauded for returning the dawn chorus to the city.
Bryce Buckland is one of those who thinks a fence is a bad idea. "I think it's a dream. Absolutely a dream," he says.
The experienced Birdlife on Grampians pest-trapper is a veteran of the Lake Rotoiti mainland island project, which could be described as a sanctuary without a fence. He says that he, Mr Dodd, and trust chairman Dave Butler - another Rotoiti veteran - have "agreed to disagree" on the wisdom of the project. Mr Buckland supports the conservation work, but says the fence is an expensive distraction and the money would be better put into trapping, or invested for more projects.
He compares it to Natureland, which can't attract enough visitors to cover its costs even though there are hordes of animals standing around waiting to be looked at. How will the secretive lives of birds attract enough people to keep the place solvent? "I'd hate to see ratepayers get dragged into that."
He says the terrain is very steep, prone to high winds and northerly storms, and damage from flooding. The devastating July 2008 storm would have "totally destroyed" the fence.
"Apart from the cost, there's no way they'll ever keep it vermin-proof, so they're going to have to constantly keep on working at it anyway; the tracks will have to be maintained to a very high standard and because that area is steep and quite unstable there'll always be slips coming down and once the fence is there they can't just push that slippage over the bank.
"There's a lot of public support behind it and it's quite right [but] I think the fence is going to be their undoing."
Original submitters against the resource consent - in concerns echoed by indefatigable Mail letter-writers - have also questioned the wisdom of using ratepayer money for the fence, and objected to the council funding a private group, particularly one that will fence off land and charge a fee for what is now publicly accessible (though the resource consent decision noted that the council could withdraw public access at any time, and no person was making profit from the scheme).
Dave Butler has been involved since the very beginning - since the Mail first reported on the enthusiasm for the scheme in February 2002.
Eleven years later, Mr Butler says the time it's taken to raise the money is actually a strength; it's allowed the trust to professionalise the operation and steer it towards something more suited to the modern world.
"We're in a much stronger position now than we would have been five years ago."
With about a dozen sanctuaries already operating in New Zealand, Mr Butler says they've learned more about fence construction, maintenance and pest eradication. He says the Brook is keen to avoid others' mistakes, including Zealandia's.
"We've really had to prove a sustainable business model at the outset before some of the recent funding would come through," he says.
Mr Dodd says people shouldn't compare the Brook to Zealandia, which got into money troubles with its "overly rosy" visitor projections.
He says the Brook trust has been deliberately conservative in that respect - 30,000 people a year, as predicted in the business case and feasibility study, which said the trust was "well-placed" to cover its ongoing costs and considered it sustainable.
Entry fees will be set as low as possible, and not as high as Zealandia's $28.50 per adult - the feasibility study indicates they'll be about $14 for adults and $7 for children, though Mr Dodd says that's not settled yet.
He agrees the site is indeed steep.
"I've heard this concern from numerous people. It's really rugged terrain up there. I can tell you from having visited numerous other fenced sanctuaries in New Zealand that these pest-proof fences have already been built on extremely steep and rugged terrain. In terms of constructing the fence it's quite do-able; it can be done."
As for slips, Mr Dodd says the Dun Mountain walkway was cut 150 years ago by "guys with picks and shovels", and since then, there's been only "very minor" slippage.
"Native forest holds slope stability in place better than anything else. We have modern engineering techniques to employ that will do an even better job of holding the road bench in place than those guys with picks and shovels.
"We're quite confident that engineering know-how, the fence design and specs are proven and we have every chance of a successful construction of the fence."
As for the dangers of the site in a storm, Mr Butler says there are good systems in place for detecting damage - an electric wire running across the top of the fence that signals when branches fall on it.
"There's always going to be issues with periodic cyclones; a lot of work goes in initially with the way the bench for the track is cut.
"We don't see that as being a major impediment, and basically build in the funds to deal with that sort of thing."
Do they need to build a fence at all? Why not sink all the money into trapping?
It really depends on what creatures you want to bring back to your site, Mr Butler says.
"It's quite clear that say in this part of the world with trapping we could potentially introduce kiwi, but that's about where it stops," he says. "There are a lot of species that can't be brought on to the mainland without a fence. The list at the Brook is an incredibly exciting one."
Mr Dodd says in the six years they've been monitoring pests with tracking tunnels - inked paper which the animals scamper over, leaving footprints behind - numbers have plateaued.
"We believe we've more or less reached the level of pest control that can be achieved through trapping and hunting, which is underscoring the need for a fence."
But he says they don't have "a fence fetish".
"You'll hear among all sorts of members of the community, including some councillors, that it's six of one, half a dozen of the other: Build a fence or use trapping and hunting. There's some truth to that but it's apples to oranges in terms of conservation objectives.
"It has come to this: The only way to bring some of these species back from the brink of extinction is through fencing and eradication."
He says the project is as much about getting people close to nature as the nature itself.
Kids who grow up without a tui in their backyards can't easily visit our offshore island sanctuaries where rescued bird species thrive, biologically crucial though those sanctuaries are.
Even if those kids walk a popular track like the Abel Tasman, they're still physically removed from the avian riches of nearby Adele Island - and that is not making them respond or care about our native animal life.
"That's why the trust has put a lot of resources and attention into developing a robust science and environmental education programme, where kids can experience an outdoor education and get their hands dirty and feet wet in a way a lot of kids these days don't get to do," Mr Dodd says. "They look at screens more than nature."
He also says it will bring economic development. Regardless of whether they hit the No 1 tourist attraction goal, he says it will become a major attraction in Nelson's tourist portfolio, for those visitors who usually visit our three national parks but bypass urban areas except to buy tickets and groceries.
Mr Butler is confident they'll make their November target; that come spring, they'll be digging into that rich soil for the first fence post.
"The momentum that there is now is pretty exciting; we see significant funding coming through month after month," he says. "You can feel it with everybody involved that now is the time we are getting there."