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IntroductIon

Animal pest eradication programmes in New Zealand were once only undertaken by the Department of Conservation (DOC) on isolated offshore islands (e.g., Bellingham et al. 2010). Successful programmes, combined with increasing public concern over the continued decline of our native species, have encouraged increasing numbers of community groups to take up the challenge of attempting animal pest eradications on the mainland. When undertaken by community groups these projects often involve very limited resources countered by inspirational generosity, which is demonstrated by the many thousands of volunteer hours that are expended. This paper summarises some of the challenges and lessons learned from personal experiences with community-based multi species animal pest eradication programmes. I identify and discuss nine key areas within a “learning by doing” approach using examples from mainland and island eradication projects in New Zealand.

LESSonS

Lesson 1: Know thine enemy and its territory.The first rule of engagement is to know what you are

dealing with and where it lives. This knowledge is required to determine whether an eradication is possible and how much it will cost. Importantly, this information needs to inform the client. People involved need to know what they are getting themselves into; a realistic view of what will be required to do this work is essential right at the start.

It is also necessary to demonstrate that there is a good reason to undertake the project. In New Zealand, eradications of invasive species are generally undertaken to protect endangered native species and/or threatened environments or to provide an environment free of animal pests as a refuge for native species.

Making this knowledge available does not necessarily require a large investment in monitoring to determine numbers of each pest species present. However, it does require knowledge about the pest species present, the effects they have on native species, and how introduced species interact with each other as well as with native species. This latter point is important because there may be prey switching or other imbalances if a predator species such as cats (Felis catus) is removed but their prey species, which might be rabbits (Oryctolagus cuniculus), are to remain.

Knowledge of local behavioural ecology is important. For example, rats are more likely to swim in summer months at Great Barrier in the northern Hauraki Gulf, most likely due to increased competition for food and dispersal of juveniles in search of their own territories. Other local environmental factors may affect eradication operations such as terrain and vegetation cover. An early understanding of potential issues that may affect the success of an eradication is vital so that sufficient time is available to plan solutions.

Similar projects conducted elsewhere can assist with planning. These may reveal issues encountered with the targeted species, non-target species, and the project environment. For example, eradication monitoring after the spread of baits within the fenced Maungatautari Ecological Island project indicated that mice may have persisted in windrows of logs and vegetation, feeding on the seeds of weedy vegetation inside the fence. Both factors may have resulted in some mice not eating bait.

At Tawharanui Regional Park, north of Auckland, livestock needed to be removed before aerial bait drops. The stock were also needed to keep grass short enough before the drops so that pasture did not provide food or shelter for rodents or restrict access to bait (Ritchie 2002). After the eradication attempt, mice were detected in long rank grass that had been retired from grazing many years before. The lesson here is that short grass is important to reduce mouse habitat and increase accessibility of bait to mice. In hindsight we should have talked to more people and considered this possibility more carefully.

Bagging them all in one go – personal reflections of a project manager about community based multi species animal pest eradication

programmes in new Zealand

J. Ritchie Environment Manager, Treescape Limited, P O Box 19387 Hamilton 3244, New Zealand. <jor@treescape.co.nz>

Abstract Animal pest eradication programmes conducted by government agencies on offshore islands have encouraged an increasing number of community groups to attempt similar projects on islands as well as the mainland. Community groups often have limited resources but balance these with inspirational generosity and many thousands of volunteer hours. I have learnt nine key lessons regarding community-driven eradication campaigns. These lessons include the need to: know the target species and its environment; produce detailed but simple plans; have a network of contacts; foster a support network of experts; develop a toolbox of techniques; understand the difficulties of detecting pests at low densities; and value the roles of people who want to improve their local environment. Taking these lessons into consideration should assist in the successful planning of future community projects of a similar nature.

Keywords: Community partnerships, limited resources, efficient management systems, increasing experience, learning by doing, continuous improvement

Pages 487-491 In: Veitch, C. R.; Clout, M. N. and Towns, D. R. (eds.). 2011. Island invasives: eradication and management. IUCN, Gland, Switzerland.

Fig. 1 Rotokare Scenic Reserve – Taranaki.

Ritchie, J. Bagging them all in one go – personal reflections of a project manager about community based multi species animal pest eradication programmes in New Zealand

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At Rotokare Scenic Reserve in Taranaki (Fig. 1), knowledge from the above two projects saw felled tree material during fence construction collected and stacked into windrows outside the fenced area. A large mob of sheep was also run inside the fenced area before the aerial bait drops so long grass was grazed to almost bare ground (Ritchie and Prankerd 2007). Although too early to be sure (the eradication only commenced in 2007), indications are that no mice survived the eradication operation. Unfortunately mice were detected and subsequently caught in late 2009; likely due to a maize truck entering to access a property on the other side of the reserve. The message here is: know your territory and plan for the inevitable if you can’t plan against it.

Lesson 2: Plan the work – work the plan Careful planning is essential. Some people find the

process of developing and writing planning documents frustrating and a diversion of resources away from doing ‘on the ground’ work. Nonetheless, the work must be meticulously planned if it is to successfully deliver on project goals. Resources are always tight for community based projects; funding sources are limited and highly competitive. These are all strong reasons why credibility has to be demonstrated and methodical project management outlined through good planning.

I use the KISS principle: “keep it simple stupid”. This may sound derogatory but it highlights that simple plans with easy language and clearly set out timelines and processes have the greatest chance of acceptance by stakeholders.

However, avoid mountains of paperwork – quality is more important than quantity. Key planning elements for the project need to be carefully defined. It may be necessary to select the best candidate out of a number of proposed projects. Stakeholders such as the community, clients, and funders may need convincing that the project is feasible.

The project manager needs to consider what would happen should they become personally unable to continue with the project. A measure of the quality of plans is whether another person with a reasonable level of skill could take over.

Each project will need an operational plan that clearly sets out how the work will be done (e.g., Prankerd 2007). This is the key document for people doing the work on the ground. Because eradications require rapid responses to new issues, operational plans need to be living working documents. They do not sit on shelves and gather dust, they need to be coffee stained, flecked with dirt and a bit torn because they are reviewed, implemented and amended constantly along the path to eradication.

Documentation is also critical; often there is a lot to think about during these projects. It is important to document how tasks were conducted in order to track progress but also to help others who follow with similar projects. Apply the KISS principle; build simple systems into operational planning and don’t over-complicate recording systems. Consider the use of graphic techniques such as GIS (Fig. 2), station diaries and simple recording forms.

Lesson 3: Eradication is done once Do it once and do it properly because it can be hard

to rebuild confidence to repeat an eradication that fails. It can be very difficult to convince stakeholders and funders that you: a) know why the eradication failed, b) have measures to prevent it happening again and c) be able to

convince people that these measures will work. Never ever compromise on quality – apply this to all aspects of the project including planning, community consultation, people, gear and equipment. Some of this may cost more but consider that the short term cost of success far outweighs the ultimate cost of failure.

Lesson 4: Manage expectations carefullyCommunity groups often do not realize that after an

eradication considerable work may be required to sustain a pest free area over the long term. For example, there is a perception that you can build a pest fence, do a bait drop and then the job is complete. In fact, all multi-species pest eradications on the mainland have required a considerable amount of ground work to remove pests remaining post aerial drops and protect against reinvasions. To my knowledge Rotokare Scenic Reserve is the only one of these areas that is pest free. A number of others are tantalisingly close and may well get there very soon but will continue to require ongoing efforts to maintain this status.

Stakeholders need to know what eradication means. There is often confusion between control and eradication. Control means some invasive animals will remain. Eradication has a zero tolerance policy; often 90% of the effort goes into getting rid of the last animal. This can be very difficult and requires incredibly hard working and dedicated people, often assisted by some very smart dogs.

It is important to sustain the effort, to be realistic about how long and what will be required to reach completion. I use continuous review and improvement and always support, listen to and nurture those people who are out there doing the work in the field, often in physically demanding and monotonous conditions.

Fig. 2 GIS based mapping system used at Lake Rotokare to map and plan responses.

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Lesson 5: Build a network of contactsDespite some claims to the contrary, there are no experts

in eradication work. Each eradication provides new lessons. I find a network of contacts invaluable. They help me in all aspects of eradication work and include a wide cross section of skills; bait manufacturers, animal pest ecologists, helicopter pilots, hunters, editors, field people, public and community relations people, iwi Maori advisers, and my husband. I can access these people whenever I need to and they always help or if they can’t, they know someone else who can. Often I will call upon a few at a time. It is always important to make sure you thank them and acknowledge their contribution.

In one example, rats were nowhere to be found for about six months after aerial baiting at Kaikoura Island. When they were detected again we had to regroup and consider our next plan of attack. To aid my understanding, and give the Motu Kaikoura Trust and its hard working ranger on the island confidence that my advice was as good as possible, I contacted a range of people including DOC island specialists, rodent ecologists at Landcare Research, the bait manufacturer, and a DNA authority at the University of Auckland. These people were invaluable and together we formulated, and continue to refine, a detection, response and prevention programme for the island.

Lesson 6: Build a support networkThe network of contacts is also invaluable for moral

support. Despite the best intentions a lot of personal energy and commitment can be invested into eradication projects.

Challenges can arise such as when a constant and seemingly unstoppable stream of rats was swimming to Kaikoura Island from Great Barrier Island, mice arrived on a maize truck at Rotokare or the barge got delayed when taking 18 tonnes of bait to an island. That is the time when I call the network, ask them to help me stay sane and reassure me that my responses are best solution (Ritchie et al. 2009). This is particularly important for people working on community based projects for whom many of these tasks are new and very daunting.

Lesson 7: Develop a toolbox of techniquesJust as a good builder rarely goes to a job without a

trusty belt pouch filled with essential tools, so too is it rare that a multi-species eradication can be completed with just one technique or tool. Different tools are often required for different species. Even for the same species, a range of tools may increase the chances of achieving eradication because getting that last animal may require novel approaches. For example, at Tawharanui, despite tracking tunnels with peanut butter and rabbit meat as lures, some rats bypassed them along fencelines but were then captured in traps. At Rotokare, despite a 50 x 50 m tracking tunnel grid (about 1100 tunnels, Fig. 2) two stoats escaped detection until they were caught in traps.

Quality must always reign over quantity. Poorly set traps, a bad shot with a rifle, or rotten bait can result in bad experiences and increase the difficulty of catching some animals.

It is also important to know how each tool works. For example, there is a common misconception that tracking tunnels measure density when they only measure presence. One busy mouse (Mus musculus) can cover a tracking card with footprints. Other issues are with rat traps, which may not always be sensitive enough to catch mice, and some toxins, which are less effective than others and for which inappropriate use can result in bait aversion. These issues

must be considered if an eradication programme is to avoid costly mistakes.

There is no need to reinvent the wheel. The network of contacts can help with knowledge about available techniques, their efficacy with specific pests, and situations where they work best. Other projects are a knowledge source that can be learned from and adapted to the current situation. To reciprocate, I in turn provide knowledge and experience to others.

Lesson 8: Absence of evidence is not evidence of absence

Detecting animal pests when at low densities is difficult, especially for animals like mice with very small home ranges. Unless funds are unlimited or the project is very small, it is often not feasible to set up the high density of tracking devices required. For example, monitoring during eradications conducted in the fenced cells at Maungatautari Ecological Island (www.maungatrust.org) found that all mice were detected using a 50 x 50m tracking grid. This may in part be due to behavioural changes by mice in low densities, when their home ranges can become measured in hectares. The Maungatautari work also found that between about October to March it was very hard to detect anything, due to abundant natural food. However, this may also be due to the fact that invertebrates quickly find bait in tunnels and reduce its attractiveness.

The point here is that absence of evidence is not evidence of absence. Intensive monitoring may be required with a range of devices over at least 2-3 years. In New Zealand, this covers all seasons and levels of detectability at least twice, which increases confidence that the last individuals were actually eliminated.

Patience is a virtue in these projects but may be hard to impress on community groups. However, we managed to do so at Rotokare where the Trust has so far resisted declaring the area pest free. They have also resisted reintroducing lost native species until late 2010 because declaration of pest free status and/or reintroduce native species too early may compromise the whole project. It is difficult to recover stakeholder confidence if pests are detected after they are assumed to have been eradicated. Furthermore, if native species are reintroduced that are sensitive to pest removal tools such as toxins and traps, the chances to quickly and effectively remove a newly detected pest may be compromised.

A lesson we have all learned doing eradication projects, especially those behind pest fences, is that pest free status may only be temporary until a cyclone or once in a lifetime thunderstorm breaches the fence. In these circumstances, an alternative approach to continuously chasing the last animal is that some may be tolerable if kept at biologically insignificant levels. In such cases, effective surveillance and pre-developed response strategies may be all that is required, although these responses need to avoid damage to native species.

Lesson 9: He tangata He tangata He tangataThe people, the people, the people. I’m going out on a

limb here – don’t we do this work for ourselves? We believe implicitly that what we are doing is the right thing to do. We are saving native species and ecosystems, empowering communities, and demonstrating that people can make a difference. Community-run eradication projects are all about people; mainly people who want some help to make a difference in their local environment.

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However, there will also be some people who oppose an eradication, whether as a genuine concern over the use of toxins, the cost of a project, or a concern that it will upset their personal freedoms, e.g., no deer to hunt after they have been eradicated. If the concerns of such individuals are considered, the planning process becomes more robust. Often the information obtained by opposing groups has been misconstrued or is incomplete and it is possible to reach a compromise. For example, at Kaikoura Island mussel farmers (Fig. 3) were initially not prepared to support the aerial baiting operation because of concern about possible impacts on shellfish. They were genuinely concerned about how the use of brodifacoum in close proximity to their farms might be perceived and also about the potential effects of brodifacoum poisoning. We met with the farmers and collated technical information, including the results of an accidental spill of 18 tonnes of bait containing brodifacoum into the sea off the South Island. This data was sent by the farmers to be independently analysed at a science laboratory.

The outcome was support to do the drops conditional on: testing mussels before and after the drops; liability insurance taken out by the Motu Kaikoura Trust; conditions

relating to undertaking the drops outside the harvesting season; and how we would fly the area immediately adjacent to the farms (Ritchie 2008).

The Rotokare project was also a challenge. A 230 hectare forest remnant with a lake in the middle surrounded by a pest-proof fence may seem small and easy. However, it also had public access in summer for boating, picnicking and walking, lambing on the surrounding properties in winter when aerial baiting took place, and 12 species of animal pests ranging from mice to goats (Capra hircus). We went through about six versions of the operational plan (Ritchie and Prankerd 2007) making changes as we gained information and more people read it. The farmers helped write the conditions for the aerial baiting contract, which required all activities to be within the fence and there were observers watching for bait going over the boundary on baiting days. Being flexible and open minded is the key when planning eradications.

Communication is the key. People need time to think about discussions and also need to feel that their opinions have been treated with respect. A common language is required with information presented in a form that suits the audience. Always serve up the good with the bad e.g., there can be adverse effects with some toxins but balance this with the advantages and gains. If both sides of the story are not presented some people may encounter contrary information then use it as evidence that information is being hidden. It is also necessary to be honest if answers are unavailable. For the Tawharanui project (Fig. 4) we didn’t know how long it took for Pestoff 20R (a brodifacoum based bait) to break down in the environment or what a livestock withholding period should be so we undertook studies to find out.

There are many misconceptions about the aerial spread of toxic baits with helicopters and these have been repeated with every eradication project I have worked on. Consent authorities often permit aerial baiting under aerial spraying sections of regional and district plans (unlike aerial spraying where there can be drift, there is no drift with aerial baiting). Another key issue is the public perception that bait is applied in an uncontrolled fashion and that much of the bait goes into the sea during operations that involve coastlines.

Such issues should be approached pragmatically and head on. Local authority planners are always open to new information but need to be satisfied that the information you provide can be substantiated. It is important to aid their understanding.

Fig. 3 Proximity of mussel farms to Kaikoura Island.

Fig. 4 Bait breakdown monitoring cage.

Fig. 5 Aerial baiting coverage at Kaikoura Island.

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Changing public perception is difficult but not impossible. It helps to view problems as challenges to be overcome. At Kaikoura Island, we did this by inviting some people who were concerned about the aerial baiting operation (Fig. 5) to observe one. They met the pilot, had a lesson on how our monitoring systems worked (random bait grids, bucket flow checks, GIS downloading of flight lines after each load) and went out in a boat to watch baiting on coastal cliffs. The latter included going ashore to look for and count baits on exposed coastal reef platforms. The result was an appreciation of the rigor employed during these operations and reduced concern.

People are always vital components of the projects I work on. They inspire and provide invaluable assistance in many ways including the championing of projects and the undertaking of the work on the ground. Often this work is voluntary and requires considerable time, effort, and cost to each individual. This is inspirational generosity – these people often repeatedly assist and then find others to expand the pool of helpers. For example, at Glenfern Sanctuary, a 230 ha pest fenced peninsula on Great Barrier (www.glenfern.org.nz), a 50 x 50 m tracking tunnel grid has been installed after the aerial spread of bait in winter 2008. Monitoring this grid monthly is hard monotonous work but it is managed by highly capable local people and a band of volunteers from all over New Zealand. Many volunteers return repeatedly to walk in steep bush placing ink cards and bait into >1100 tunnels. The same is the case at Rotokare. The knowledge these people build up should not be undervalued.

We encourage these participants to write notes in project diaries of any ideas, observations they might have. Acknowledging these efforts is essential. We do this by newsletter updates, barbecues, celebrations, and invitations to special events. One such event at Tawharanui was the release of North Island brown kiwi (Apteryx mantelli) in 2006 after a 50 year absence from the Auckland mainland (Fig. 6). Two hundred and fifty people came to the first release on a wet, wild day. But it was one way to celebrate, encourage and reward these workers and their community.

AcKnoWLEdGEMEntS

I would like to thank Cam Speedy and Sharon Kast for reviewing this paper. I would also like to acknowledge the Auckland Regional Council, Rotokare Scenic Reserve Trust, Motu Kaikoura Trust, Glenfern Sanctuary Trust, Maungatautari Ecological Island Trust, Xcluder Pest Proof

Fencing Company, the Dancing Star Foundation, Skywork Helicopters Limited and Animal Control Products Limited for providing me with the opportunity to both work on inspiring projects and with dedicated people. I would also like to acknowledge the Department of Conservation for paving the eradication pathway in New Zealand and to the many DOC staff who have provided me with advice and support.

I dedicate this paper to Tony Bouzaid, the driving force behind Glenfern Sanctuary.

rEFErEncESBellingham P.J.; Towns D.R.; Cameron E.K.; Davis J.J.; Wardle D.A.;

Wilmshurst J.M. and Mulder C.P.H. 2010. New Zealand island restoration: seabirds, predators and the importance of history. New Zealand Journal of Ecology 34: 115-136.

Prankerd, K. 2007. Rotokare Scenic Reserve Trust pest eradication operational plan. Produced for Rotokare Scenic Reserve Trust.

Ritchie, J. 2002. Tawharanui Regional Park Open Sanctuary operational plan 2000-2005. Produced for Auckland Regional Council.

Ritchie, J. and Prankerd, K. 2007. Rotokare Scenic Reserve animal pest eradication plan. Produced for Rotokare Scenic Reserve Trust.

Ritchie, J. 2008. Kaikoura Island eradication operational plan. Produced for Motu Kaikoura Trust.

Ritchie, J.; Miller, R.; Galloway, D. and Scarlett, W. 2009. Motu Kaikoura Scenic Reserve biosecurity plan (Draft 2). Produced for Motu Kaikoura Trust.

Fig. 6 Return of kiwi to Tawharanui Open Sanctuary.