Judy Gilbert - Founding Trustee and Voluntary Manager of Windy Hill Sanctuary

Interview with BARRY SCOTT

How did the concept of a sanctuary at Windy Hill arise?

In the autumn of 1996 I set up some traps around my house on Rosalie Bay Road, like you have to, and was rather shocked to find I caught 60-70 rats. So, another Windy Hill shareholder, who at the time was studying for a Diploma in Environmental Management at the University of Auckland, and myself put together a simple pest management plan, which we took to the Windy Hill Company AGM in 1998, and it was approved. In April 1999 we managed to get enough money, which was mostly donations from myself and my husband, found a person to work with us, and set out around 100 rat traps and began trapping, without knowing much about what we were doing. Early on Steve Hix, a biodiversity officer at Auckland Council, heard what we were doing and came out to the island and set us right about how we needed to lay out traps and how to space the trap stations. By the end of 1999 we had a much better system starting to evolve and neighbours on Benthorn farm, Peter and Helga Speck, were interested to join us, so we took on another employee and worked together. Now 25 years on, we have expanded out as interested landowners have approached us or we have gone to them. We started with just the three blocks owned by Windy Hill Company and now the Sanctuary comprises 16 blocks owned by 58 people, either individually or collectively. Landowners sign up to the Windy Hill Rosalie Bay Catchment Trust through a simple Working Agreement, which describes the responsibilities of both partners. This is the permission from landowners for the Trust to carry out pest management, species monitoring, research, and biodiversity surveys on their property. Fairly early on we realized that the employees shouldn’t be the responsibility of any individual landowner so we formed a Charitable Trust in 2001 and that is the employing entity.  

Were all landowners aligned with the vision?

Once the Windy Hill pest management project was up and running landowners approached us wanting to join in. Among the 58 people involved there is a core group of committed conservationists and then there are people that are just happy to have the work done if it does not cost much or intrude on their privacy and sense of sovereignty. Some of the absentee owners say, “just do it”. There is, of course, a range of landowner values and attitudes about the Sanctuary vision and we are mindful that we are working on their property and adapt our programme if necessary. For example, those landowners who don’t want the risk of toxins have traps only. In all the years we have been running, just two blocks have been sold, and in both cases the new landowners have come on board willingly. All landowners appreciate having less pests on their properties. It is interesting to note a level of assumption that has crept in overtime with some landowners thinking it is our responsibility to manage all the pests on their property. It has always been a partnership. We have been there to help manage pests and monitor the biodiversity to the best of our capacity. We undertake to get the funding, employ the people, do the pest management and biodiversity monitoring. The roles and responsibilities are ongoing conversations. 

Besides rats, we are also keeping on top of feral cats and culling feral pigs. Pigs are challenging, especially the last few years with La Niña, where we have seen a big increase in numbers along the east coast. We have a local hunter who works hard to keep the numbers down, but for some landowners that has not been enough so we have had to review how we manage pigs in partnership with the landowners. Sometimes we have brought in additional hunters to get the numbers down; in 2022 around 50 were culled and so far this year 35. It is important to remember that all we are doing is pest suppression. We are just keeping the lid on so the native species have a lot more of an opportunity to survive. Sanctuaries like ours, which is open, don’t have such high biodiversity outcomes as Glenfern (fenced) or Motu Kaikōura (island); however, both have re-invasions. Sanctuaries like Maungatautari with a ringed fence do better, and pest free islands like Hauturu and the Mokohinau Islands where predators are totally excluded have the best outcomes.

How did you become the leader of this venture? 

My second name is tenacious. So, once I start something I have to finish it even though this has no end at this point. This has been an organic process where we have planned for what we could manage. A key development was release of The New Zealand Biodiversity Strategy in 2000, as this was the first time private land was recognized as holding a lot of NZ’s biodiversity.

This meant that our work was now guided by a nationally recognized strategy. A flow on from that strategy was the channelling of funding through DOC to private landowners to protect biodiversity. We were one of the first cabs off the ranks followed soon after by Glenfern. We got in early for some of that funding. From those early days the Local Board has always been supportive and approved funding. 

Where does your passion for conservation come from?

I have owned the land on Aotea since I was 19 - it has become my turangawaewae. By osmosis I got to know the bush, all its layers and how the bush flourishes. When we first bought the property there was 100 acres of grass and without any planting done there is now less than a half acre left after 52 years. As a teenager I spent a lot of time on boats and when I first came out to Barrier I fell in love with the place. That was my Barrier connection till I came to live here in 1984. I am a very project focused person who gets up every morning and thinks about what else I can do. When you first come here you are focused on house and garden for the first couple of years but after that you look up and ask yourself what else can be done here for the community and island. So, this fledgling project kept growing from the initial 20 ha at Windy Hill to around 150 ha when the Benthorn Farm was added. When we re-introduced robins to the island in 2004 we realized we needed more protected land for them to thrive. So, by 2006 we were ready to take on another big chunk. As we expanded a pest management plan was developed for each new area. First there was Little Windy Hill in 1999, Benthorn Farm in 2001, and then in 2006 we took on four more properties on the ridge going south to Rosalie Bay, which we called Big Windy. In 2009 we took on another chunk called Rosalie Bay and in 2016 added Derek Bell’s 137 ha block (Taumata), which has a QEII covenant over much of it(1), although this block has recently become independent. Finally, in 2019 we took on another DOC block and private block on the Tryphena Ridge. So, the growth has been very organic, shaped by the properties that have joined. We have agreements signed with two more landowners adding another 83 ha to the Sanctuary area over the next 18 months. These pest managed areas enable us to set up various field trials on the effectiveness of different traps (e.g. Good Nature) and bait regimes, as well as make historical comparisons with older sites. We also have an unmanaged Control site nearby for comparison. 

So much of what you do is science led?

Yes, we have learnt a lot. We undertake a lot of citizen science and our pest management programme is underpinned by science. I wrote a 10-part series for the Barrier Bulletin on Citizen Science, which covered a range of our research activities. For example, we have examined the impact of bait on ruru and trialled the use of worm farms to break down used bait.

We had worm casts professionally tested after six months which showed they did not contain any detectable levels of toxin. We chose worms as they are held up as being able to revitalize almost anything. Given there was no detectable level of the bait after passing through the worm farm that result has enabled us to deal with all our excess bait in large worm farms on site. 

We monitor rat abundance four times per year following standard DOC methodology. We constantly check for the efficacy of what we are trialling. Since 2011 we have synchronized our rat monitoring times with those at Glenfern. More recently OME, Okiwi, and Motu Kaikōura have adopted the same time frames. This gives us a regional picture of rat activity and how well our rat suppression is working. 

Since 2006 we have been monitoring wētā, lizards and invertebrates, giving us some good long-term data. We have 45 onduline stacks spread through the pest managed areas which we use to monitor lizards and invertebrates every six months. We record numbers and species of lizards and invertebrates by visual inspection. We have short lengths of bamboo in trees for wētā in which we measure occupancy. When we started this monitoring in 2006 we compared 10 sites in Windy Hill (pest managed) to 10 control sites (no pest management) and found 30-40% occupancy in the former and none in the latter. Over the first year we found just one wētā and no lizards at all in the unmanaged site. These were graphic illustrations of the benefits of predator control.

We started comprehensive annual bird monitoring in 2000 and this is now supported with the annual Aotea Bird Count. We had a DOC ecologist initially, then John Ogden took over in 2008 to report the data.  John is our ecological advisor and has been a huge help in setting up and analysing the results of the various trials we have carried out(2). This year we plan to carry out a comprehensive analysis of pig numbers and damage as there is currently little information on abundance of these animals across Aotea. 

We have also carried out freshwater stream monitoring over the years to NIWA standards determining species presence and abundance. We found healthy populations of kōura – the native crayfish.

In 2012 we carried out a fungal foray led by Marg Pardine over a five-day period with my team and the last day with the public. We have also funded surveys of Hochstetter frogs in both Windy Hill (2010) and Te Paparahi (2012, 2015 and 2021). Unfortunately, none were found in the Windy Hill Sanctuary, but there is a stable population present in Te Paparahi(3). We have also carried out skink and gecko surveys at Windy Hill. Herpetologist Trent Bell created a beautiful field guide to all the lizards in the Sanctuary enabling the field team to distinguish between gecko species and skink species. We have built up a lot of resources and information which we share freely. I have recently been in discussion with George Perry, who has arranged for a student to analyse much more fully all the invertebrate and lizard data we have collected and write it up for publication. There is still much to learn.

We have undertaken 5 seabird surveys, three with the help of Jo Sim from DabChickNZ.  20 active black petrel/tākoketai burrows have been found within the sanctuary and several ōi/grey faced petrel burrows, although the latter are often in sites that are very difficult to get to. During her most recent survey in April of this year, she discovered two Cooks Petrel burrows. 

All our toxin use is underpinned with science. We are using the socially most acceptable bait we can, which is diphacenone. We have trialled various pellet toxins but found rats much prefer paste baits. All bait and trap stations are checked every 3 months with those on the perimeter of the pest managed areas monthly. We are able to check stations this infrequently due to many years of keeping the rats suppressed. We have over 100 km of tracks which require constant maintenance to keep them clear. After storms there is quite a lot of work re-opening tracks. 

What is the Trust's source of income?

We have raised around $4m since we started which is extraordinary. One of the key elements in raising money is telling the compelling story. In our story we tell how our work not only benefits the environment but also the social and local economy too. We have a high level of financial accountability and are always on time with reports for our funders. Over the years we have had funding from DOC, Auckland Regional Council, the Local Board, Auckland Council, Foundation North, Lotteries, QEII National Trust, and others. As philanthropists, my husband and I put a big chunk in each year, and each landowner makes a donation towards the work on their property.  DOC has been very good over the years with their Community Conservation Partnership Fund but last year we failed to get any funding as did everyone on Barrier. Three year funding is often approved as funders like Lotteries, Foundation North and the Department of Conservation, accept that restoring biodiversity is a long term goal.

After 150 years of trashing the environment it is going to take a long time to restore it. Of the $4m we have raised over the 25 years, over $2m has gone back into the community as wages, which is a solid contribution to the economic well-being of the island. There is also a huge amount of voluntary work. All our Trustees work on a voluntary basis. Five landowners give their time to trapping around their properties while the remainder of the work is carried out by our field team. Currently, the annual budget for employees is around $250,000 – a lot of money to raise. We have also taken on other projects to support the Trust. In 2018 we picked up the community aspiration to have a native plant Nursery on the island. This was a good opportunity to utilise our capacity to create, manifest and fund a new project, which created two more jobs. The Nursery has now been taken over by Motu Community Nursery Social Enterprises. 

The Trust previously had the contract to run the island biosecurity programme from 2003 to 2022 – an array of traps and bait stations around all the wharves, boat ramps, and jetties - which generated income for the Trust. Since 2022 Auckland Council has become our biggest funder with funds generated by their Natural Environment Targeted Rate. The Sanctuary long term integrated pest management and biodiversity monitoring and ecological significance has made us a BioFocus area in the Auckland Council plan and a worthwhile project to fund. Within the Sanctuary is 250 ha of QEII covenanted land and three DOC blocks, which adds a layer of perpetuity to their protection. 

Now that you have been going for 25 years what changes do you notice?

Definitely more birds – monitoring shows a lift in kākā, kererū, and tūī. More lizards than in the unmanaged block. So, the biodiversity is definitely improved and this is often commented on by local visitors. But it is still not nearly as good as it could be if we were a pest free island(4),(5). Aotea could be magnificent in its species abundance like Hauturu if only we had the courage to do it. We are surrounded by pest free islands – Rakitu, Mercury, Cuvier, and the Mokohinau islands. Technically it is feasible but socially we are a long way off that licence because we have not yet carried out a survey of all residents and ratepayers and asked how we can ecologically protect this motu. It’s something AGBET or the Ecovision project could do. What is needed is a face-to-face survey with as many residents and ratepayers as possible, similar to the one undertaken for the Tū Mai Taonga project – we need to gauge support for a predator free island and how it might be done. Until we do that we are only guessing at how much support there is on the island for becoming pest free. Finding out people’s views will help what information needs to be shared and what long term plans need to be made. 

Have we lost our ambition?

The concerns people raised at the time could well be answered by the success of the aerial eradication – for example, nothing was made of the fact that mussels suspended in cages around the island were unaffected by the toxin drop. There is still no post eradication plan for the island and there must be a written record prepared of what was achieved on Rakitu. Post drop monitoring is essential as it will become an important long term record of how the biodiversity of the island recovers. Predator free 2050 has really main-streamed pest management and thousands of kiwis are now engaged in pest management and realise how essential it is. The Aotea Trap Library has been hugely successful – there have never been as many people carrying out pest control on the island as now. But one big concern if we get rid of the rats on Aotea is the mice. Zealandia, Maungatautari, and Tāwharanui Regional Park all failed to get rid of their mice after the rats were eradicated.  So, the problem of mice has to be addressed. Maybe there will be a mouse specific toxin in the future.

How do you deal with the naysayers?

All concerns are valid but one has to accept that for some there will never be a justification for the use of toxins. Listen to what they have to say and keep putting forward what we have learnt here. With the continuing alarming loss of biodiversity around the world from the impacts of climate change and habitat loss we can’t afford to muck around much longer. We are not short of humans, but we are getting mighty short of critters. I view the use of toxins to eradicate pests here like chemotherapy – when a person is sick heavy duty toxins are used to kill off the unwanted cancer cells to sustain life – Aotea is the body in need of toxins to sustain the native species here.  

What have been the lows for you?

The biggest low is that after 25 years Aotea is not already pest free and our native species thriving rather than being in free-fall except in protected areas. Another biggie is the lack of new tools for predator control. What we started with in 1999 traps or bait stations has not improved. Many of the new solutions are too complicated and expensive to put in place and don’t appear to work all that well in areas where pests are already suppressed.  New tools are often trialled in a virgin forest not pest suppressed  areas like ours. Those developing these tools should trial at sites such as ours to really test their long-term effectiveness – every project aims to get to zero or low densities of rats after all.  The tools also need to be deployed at scale and consider the behaviour and activity of pests. A good example is the trapping of cats during a particular phase of the moon when they are very active, something Cam Speedy and Sam the Trap Man emphasized at the Ecovision Pestival last year, and something Māori have been aware of for a long time. While we can do this for cat traps it is not possible for thousands of rat traps. There is also the need to understand that what might be a ‘hotspot’ for a particular pest at one time will change, depending on availability of food sources and the like. You need to ruthlessly suppress over entire landscapes as pest suppressed areas are like a giant lure for rats. They are very smart animals, and we think they can smell abundant food and less competition. Having to invest a lot of time, effort and money to sustain smallish pest suppressed areas on the island for the foreseeable future is like pouring funds down a black hole. On all levels, a pest free island makes great sense.

You have been doing this now for 25 years so what is your succession plan?

In January, the succession plan commenced with Louise Mack, ex DoC, taking on the role of managing field operations. This leaves me with overall governance, communications, funding, and working with visitors, scientists & landowners. Given the size of the enterprise Lou will progressively take over different chunks of the Sanctuary management over the next few years. 

If the new person wants to change how things are done, how will you respond? 

Lou and new field Manager Jordan Scarlett, who began in November last year, are already bringing rigour to elements of our programme. It is awesome to have such highly qualified people leading our field team of six. Our entire team now is the most qualified we have ever had. For me, it’s very much about letting go and trusting in their abilities to continue the mahi to a high standard. 

Any other highlights?

An unexpected highlight has come through the 30 plus people we have employed over time. As someone never short of a job or sense of purposefulness I have delighted in seeing the commitment, skill, and sense of achievement in employees who have skilled up and treasured their job. Many have become proud of the conservation professionalism developed and the self-esteem that goes with that. 

Our relationship with Ngāti Rehua Ngātiwai ki Aotea is one of mutual respect. We have a long-standing MOU with their Trust Board and they have provided the cultural richness to our three North Island robin translocations to the island. The iwi led Tū Mai Taonga has a Technical Advisory Group, which I sit on to share the learnings from our Sanctuary. 

Another highlight has been the close relationships formed with University of Auckland and Massey University, and the 3 doctorate and 5 master students who have carried out research in the Sanctuary. Importantly, while our team is able to guide and pass on knowledge to them, we also learn from them. There have been some excellent botanical and vegetation surveys carried out here although there is still a gap in our knowledge of the lichen and moss flora within the Sanctuary – we have experts in this field planned for a visit in October this year.  

The Windy Hill Sanctuary is now well regarded throughout New Zealand as a model for conservation on private land and has received several awards including the:

• Green Ribbon Award for Caring for Biodiversity from the Ministry for the Environment (2003) 

• E-Award for Caring for the Land and Biodiversity from the Auckland Regional Council (2003) 

• Stella Francis Award for Conservation Excellence from the Department of Conservation (2004)

• Mayoral Conservation Award (Eradication) from Auckland Council. 

• NZ Biosecurity Awards Runner Up (2021)

I never envisaged we would still be going after 25 years. Over that time 66,000 rats have been trapped and probably the same number poisoned making it over 120,000 rats that have been removed from this environment! Plus 452 feral cats and 352 feral pigs culled and 66 wasp nests!

So, what is your long-term vision?

It remains the same as it was 25 years ago and that is to see a pest free Aotea | Great Barrier Island. It always has been. Imagine if this island was like Hauturu/Little Barrier. It would be just magical. All the resources we now put into pest control could be redirected towards translocating back to Aotea the many threatened species we have lost, like bellbirds, saddlebacks, stitchbirds, and rifleman. Returning lost lizards and invertebrates. That’s my big dream. With Tū Mai Taonga and iwi also having the same dream of restoring the mauri of Aotea, we may, in time, together, realise it. 

Acknowledgements

John Ogden (Trustee and Science Advisor), Rose Harland (Trustee and Community Conversations), Sue Thompson (Trust Administration), The Sanctuary Field Team, the 58 property owners who have placed the responsibility for the ecological restoration of their properties with the Trust, and the many others who have volunteered or helped the Trust, often pro bono, over many years. Many of these are named in a recent Windy Hill Sanctuary Newsletter(6).

Images & Video

All images are from the Windy Hill and Rosalie Bay Catchment Trust Photo Collection. Thanks to Steve Young for sharing his video interview with Judy in November 2023.

References

1. Judy Gilbert (2019). Twenty years of ecological restoration. Windy Hill Rosalie Bay Catchment Trust Report. 

2. John Ogden and Judy Gilbert were the founding trustees of the Great Barrier Island Environmental Trust (GBIET) in November 2003. Environmental News #47. Summer 2023.

3. Judy Gilbert (2021). Hochstetter’s frogs hanging in there on Aotea. Environmental News #46. Winter 2022, pages 8-9.

4. Auckland Council video of Windy Hill Sanctuary: https://vimeo.com/scienceagency/review/956887877/5129e0f99c

5. Steve Young interviews Judy Gilbert (2023): https://youtu.be/YgnSLuSzBkw

6. Judy Gilbert (2024). Influences on an Island Sanctuary. Windy Hill Sanctuary Newsletter #46 June 2024.