- 2.1 Effectiveness and cost of current control measures in achieving stated pastoral/environmental goals.
- 2.2 Incidence of costs
- 2.3 Severity and distribution of any impact on native flora and fauna.
- 2.4 Humaneness.
- 2.5 The health and social well-being of people.
- 2.6 The use and enjoyment of the public of lands and waters to which they have right of access.
2. Assessment of current control measures
Rabbits were initially introduced, in the mid eighteenth century, to sub-Antarctic islands of the Southern Ocean along with pigs and goats as a source of food for castaways. By 1830 they were being distributed throughout New Zealand for sport. As the land opened up for grazing they spread quickly and by 1870 were regarded as pests. They reached peak abundance by 1890 and vast numbers were killed for industries based on their products (Gibb and Williams).
The need for rabbit control was first recognised in legislative form with the Rabbit Nuisance Act in 1876. Rabbit control was the responsibility of the land owners and a controlling board of landholders levied rates to cover expenses such as inspectors. These boards were not effective and were abolished in 1882.
In 1886 The Rabbit Control Act came into force. Boards were reintroduced and the government provided a 1:1 subsidy on landholder rates-an important incentive. However, few boards were set up (six by 1920) and rabbit control was localised.
A new era of control began with legislation in 1947. This established a Rabbit Destruction Council with local Rabbit Boards pursuing a ‘killer policy’. Important features of the Act were:
- payment of rates by landholders based on area of property or stock carried, to locally elected rabbit boards;
- a 1:1 subsidy by the government on all rates collected;
- all work was done by trained employees of the board;
- rabbits and their products were decommercialised.
This policy was dramatically successful. It was aided, in the mid 1950s, by aerially-dropped baits and the poison sodium monofluoroacetate (1080) replacing strychnine. By the 1960s, apart from hot spots in inland Otago and Canterbury, Marlborough and parts of the east coast of the North Island, rabbits were no longer considered a threat to agricultural production.
In association with this successful period of control since World War II, rabbit habitat quality and hence rabbit numbers declined in many parts of New Zealand, especially in moist, lowland areas. This was because agricultural development regimes, involving pasture improvement and grazing control, followed the initial intensified rabbit control. Therefore the long term strategy for rabbit control is to modify, where possible, the rabbit habitat so that it is less favourable to rabbits. This is more effective than the short term strategy of simply killing rabbits.
The Agricultural Pest Destruction Act was passed in 1967 to address the problem of rabbits and other vertebrate pests. The Agriculture Pest Destruction Council (APDC) became the successor to the Rabbit Destruction Council and pest boards replaced rabbit boards. Costs of control were subject to review and in 1980 the dollar for dollar subsidy by the government was replaced by a single grant for the APDC to distribute. In 1983 the Agriculture Review Committee reported that rabbit populations were generally at acceptable levels over most of the country, except in drier districts where severe problems existed. It recommended that:
- rabbits should not be considered differently from other farm pests;
- land should be classified according to its proneness to rabbits;
- government funding should be phased out except for those areas where environmental qualities were threatened; and
- where land was not prone to rabbits, rabbit control rates should not be levied (Application).
When MAF considered an application to introduce myxomatosis in 1987 this was not supported by the Parliamentary Commissioner for the Environment, but, in recognition that rabbits remained a problem in semi-arid areas, the Commissioner recommended the establishment of a task force to address the problem through the development of integrated land management strategies.
In 1988 the Task Force recommended:
- that the government continue to invest in rabbit management, primarily for resource conservation, but also as partial compensation for the denial of myxomatosis;
- that this investment be concentrated on the approximately 280,000 ha of highly rabbit-prone land in the dry tussock grasslands;
- that the cornerstone of future rabbit and land management in the semi-arid regions should be a property plan;
- that research on the interactions between land type, land use and natural rabbit control agents (biological controls), particularly predators, must be intensified; and
- that funding for the programme be via local government under new contractual arrangements.
These recommendations formed the basis of the Rabbit and Land Management Programme (RLMP) that became operational with the establishment of regional councils in 1989. The review of local government that led to the formation of regional councils abolished the former pest boards and transferred the responsibilities for vertebrate pests to regional councils.
The overall goal of the RLMP was to improve the long-term sustainability of land resources and consequently rural communities in rabbit-prone areas. The programme ran from 1989-95. It covered 400,000 ha in Otago, Canterbury and Marlborough, ultimately encompassing 97 properties. It became a partnership between central and regional government and landowners to evolve an integrated strategy of land management with a total combined investment of around $35 million (Taylor Baines and Associates, 1990). The monitoring and research involved in the programme led to a better understanding of the problem - of rabbits and their predators, ecosystems, farm systems and economics, land use options, the need for agencies and communities to work in partnership and how to measure progress toward sustainability. Other benefits from the programme included the construction of extensive rabbit fencing and a reduction in the poisoning frequency (Application).
Despite the gains from the RLMP rabbits remain a significant obstacle to achieving sustainable land management in moderate to extremely high rabbit prone areas. Surveys during the RLMP showed that the cost of control exceeded income in many farms having moderate to extreme rabbit prone land and that taxpayer-ratepayer subsidies were supporting rabbit control.
The Application outlines the development of the present Regional Pest Management Strategies (RPMS). In 1993 the Biosecurity Act came into effect, replacing all former pest control legislation. It brought a cost-benefit justification that must be met before control requirements could be imposed. This justification requires that the benefits of undertaking pest control exceed the costs and that the benefits of control through a RPMS must exceed the benefits of individual action. The Act requires that "beneficiaries" and "exacerbators" pay.
Government subsidies for rabbit control, which had been in effect since 1887, finally came to an end in 1995.
Commercial trade of feral rabbits also became possible for the first time in several decades.
The rabbit lost its status as a pest of national importance and became a pest of regional importance. This had the effect of allowing different responses to different types and degrees of severity of feral rabbit problem.
Enforceable rabbit control is progressively being brought under new RPMS’s established through public consultative processes in each region of New Zealand where rabbits are declared to be a pest. There are 16 regional councils (which include the four district councils that are unitary authorities). Thirteen of these have controls in their RPMS for rabbits. Each RPMS has nominated its own regional council as the management agency for its rabbit control strategy.
The Crown may be bound legally by a RPMS through an Order in Council. Such an Order in Council would need to define the extent to which the strategy would impose costs and obligations on the Crown. In deciding policy for the Biosecurity Act, Cabinet agreed that the Crown would be bound only in respect of pests on its land which are imposing external costs, i.e. the Crown should take a ‘good neighbour’ approach.
2.1 Effectiveness and cost of current control measures in achieving stated pastoral/environmental goals.
Pastoral and environmental goals
The goals of the current control programme are not stated in the Application but the rabbit control plans of each RPMS define the upper limits of rabbit numbers measured on the McLean scale for an area, beyond which control is required.
Effectiveness of current control measures
| The RCD Applicant Group in their Response to Review Reports, Part Two, states: | |
| "Despite these obligations, (i.e. the legal requirements of the RPMS and Land Law Act, 1948) and the best efforts of most landholders, the current range of control tools does not allow sustainable management of the rabbit pest." | |
| Also, in relation to the effectiveness of control on the most rabbit prone land the Application shows no optimism: | |
| "Regardless of land use, rabbit control using current tools is clearly unaffordable on much of the most rabbit-prone land. Because of soil type, climate, altitude, slope and other inherent conditions, the options to modify habitats to reduce proneness are strictly limited. In considering the control methods available, the Rabbit and Land Management Task Force (1988) recognised that, for these areas, none of the current alternatives will significantly reduce the need for, or the consequent cost of, rabbit control." | |
The main techniques currently used in New Zealand for controlling rabbit numbers are poisoning with 1080 and pindone, shooting, trapping and gassing.
Poisoning with 1080 is the primary means of rabbit control and the Application claims this to be the most cost effective method for lowering very high rabbit numbers. Although kill rates exceeding 90% are common it is not unusual for rabbit numbers to increase rapidly so that poisoning with 1080 needs to be repeated every 3-5 years. The poison is usually applied in the autumn and winter but summer poisonings have been resumed this year and late winter applications will occur in the future in some areas. There is some anecdotal evidence that there has been an increase in the rate of recovery of rabbit numbers in some areas of the South Island in the past 2-3 years and a consequential shorter interval between poisoning with 1080. The reason is unknown but the increase in rabbit numbers may be related to favourable seasons resulting in ideal conditions for rabbits.
The Application and many submitters refer to the problem of 1080 poison-shyness amongst rabbits although there is little documented scientific evidence for this. (Ecosystems).
The present control programme’s reliance on large and frequent applications of a single toxin, 1080, means it is vulnerable to the adaptiveness of the rabbit, changes in community values and changes in market forces outside of New Zealand. There is increasing awareness and concern by most New Zealanders about the widespread use of poisons, such as 1080, in the environment. New Zealand uses approximately 4 tonnes of 1080 a year and about 500 kg is used to control rabbits (Parkes, 1995). The Parliamentary Commissioner for the Environment (1994) warns:
"Continued heavy reliance on 1080, or any other single toxin, is not advisable over the long term."
Secondary control methods, which include shooting, trapping, fencing and gassing are used to variable effect. Natural geographic rabbit boundaries and rabbit proof fences also assist in the application of these control measures by enabling manageable blocks to be selected for control operations and by limiting re-infestation of the blocks. The disadvantage with rabbit proof fences is that they are costly to set up and maintain.
A professional rabbiter who uses secondary control methods, is critical of the Application and the regional councils because of their promotion of 1080 poison as the only effective means of control. He claims his secondary control methods, used in close cooperation with land owners, have proven to be very effective and cheaper than 1080 on extremely rabbit prone land. However, most farmers have mixed success with secondary control and find that it only serves to delay the inevitable 1080 poisoning by 1-2 years.
A few submitters called for additional methods of rabbit control such as supplementing the diet of cats in the winter so that there was a high number of predators in spring when rabbits started to breed, the return of strychnine, and the introduction of myxomatosis.
Farm management practices are inevitably disrupted by large-scale poisoning operations. Areas treated with poisoned bait must be destocked prior to and following the control operations. Often land must be retired for up to 3 months during critical winter periods or stock losses will result. This is a major problem for small landowners who have to move all of their stock off the property during a poisoning operation. Properties near built up areas may not be permitted to use poisons and effective rabbit control may not be attainable.
The control of rabbits is very frustrating for farmers. Despite learning a great deal about the technical issues and management of control from the Rabbit and Land Management Programme, and many affected communities taking responsibility for the control of the pest, the potential of the rabbits to disrupt the viability of enterprises and degrade the ecosystem remains as great as ever. Low farm returns compound the problem.
| The High Country Trustees, an organisation comprised of 45 families who live and work in the high country from Canterbury to Southland comment: | |
| "We would like to strongly indicate that the current position is one of farmers having insufficient funds for adequate rabbit control, leading towards an increase in numbers, potential loss of the gains made under the Rabbit and Land Management Programme, and unsustainable land management situations. In our view the potential land damage from such an event is untenable under the Resource Management Act, as well as disastrous for the rural community." | |
Some submitters criticise land management strategies that encourage high rabbit densities. They call for a closer integration of rabbit and land management research, better identification of rabbit-prone lands, control strategies modified for bait-shy rabbits and more subdivision of the worst affected areas. Other suggestions include development of unfavourable habitat, scrub control and root raking, and retirement of affected land. Land use changes, such as forestry, are suggested but these other land use options are also limited by the risks associated with rabbits. There is a call for land owners who do nothing to control rabbits to be held to account.
Rabbit harvesting
See section 5.11.
Retirement of land from production
A few submitters suggested that some land should be retired from production because its use for production is ecologically unsound. Rabbit control and land restoration would then become a responsibility of the Crown rather than individuals.
Some land overrun with rabbits has in fact been retired from production, but the farmer remains liable for the cost of rabbit control. The costs of control and restoration are beyond the resources of the farmer and it is unlikely that the costs will be met from pastoral farming. Such land, particularly that in the high country, in addition to conservation and environmental values, has social and amenity values as discussed in section 1.4. There appears, however, to be no strategy to ensure that these values are preserved. The incidence of costs is considered in section 2.2.
Parkes (1995) states that the surrender of pastoral rights to the conservation estate is expected for a total of 954 km2 in 27 leases (3.9% of the total pastoral lease area). In addition to this process, some leases have been bought by the Crown so that the properties may be used as part of the settlement of Ngai Tahu’s claim before the Waitangi Tribunal and parts of other leases have been acquired by DoC. Some of this land carries rabbits and this will mean that DoC will have an increasing rabbit problem.
If rabbit management is to be sustained and management responses are to be commensurate with the risks and benefits, costs and risks must be borne equitably by those who benefit. The risks and benefits are relatively clear on productive freehold land, but are currently less clear in the South Island high country, particularly as the tenure of the pastoral leases has changed (Parkes, 1995).
Costs
According to the Application, annual costs of rabbit control in New Zealand are at least $22 million. This is almost double the original estimate of Brown and Copeland. Refer to section 8.
Many farmers are finding it difficult to afford rabbit control and some cannot. In Southland where rabbit populations tend to be of low to medium density, control costs between $2.00-$40.00 per hectare. Costs on moderate to extremely highly prone land vary but are generally $40-$70 per hectare. On one property in an area of extremely high rabbit proneness the projected cost of control with 1080 was $100 per hectare.
| Submitters stated that the high costs of rabbit control restrict the development of farms and their profitability. For example, one submitter (490) who owns a 4,000 hectare property has 250 hectares where rabbits are reaching 7 and 8 on the McLean scale two years after 1080 poisoning: | |
| "Rabbit control costs me directly $35,000 to $40,000 every year and indirectly a lot of lost opportunities through lost grazing potential, deferred maintenance spending on weed control and capital replacement items." | |
Another season of low wool prices means escalating pest control costs will take their toll on farming families. The financial limitations mean that a cheaper alternative to large-scale aerial 1080 poisoning is needed if farming operations are to remain viable at today’s commodity prices. The ongoing costs of rabbit control often exceed the economic return from the land and are a major constraint to the implementation of sustainable land use in areas of high rabbit proneness. Some farmers are able to cross-subsidise, using the better returns from lower rabbit prone areas to assist rabbit control in the areas of high proneness.
| The current high cost structures of control are viewed by some of the submitters as a recipe for disaster. They see the present system as poorly managed and economically unsustainable. | |
| "While the Rabbit and Land Management Programme made a short term impact on rabbit numbers, the net result after the close of the programme has been to leave farmers exactly where they were in terms of rabbit numbers and no solution in sight. In addition, the programme eliminated any cash reserves they may have had and has left them with an economically unsustainable, poorly managed pest management strategy operated by the Regional Council." (Mackenzie District Council - 239). | |
A 1992/93 survey of 18 of the 97 properties in the RLMP showed the costs of rabbit control exceeded income in 10%, 75% and 90% of land in the moderate, high and extreme rabbit-prone classes respectively. It concluded that while rabbit numbers had been reduced in all but some intractable areas of Otago, it had been at the expense of a combined taxpayer-ratepayer subsidy of 70%. The economic viability of many of the properties taking part in the programme was doubtful (Parkes, 1995).
As stated earlier, DoC spent $397,000 in the 1996/97 year for rabbit control. Control is often for their "good neighbour" role rather than for conservation gain.
In the most rabbit-prone and most rabbit affected localities, the costs of rabbit control by conventional methods cannot be financially justified by the returns that reduced rabbit numbers bring to the business. Rabbit control at present costs does not appear to be sustainable in the long term.
2.2 Incidence of costs
The costs of rabbit control are met by the land holder who may also be the land owner.
| The Crown is the largest single land owner in the rabbit prone country: conservation lands; unoccupied Crown land; Ministry of Defence land; all pastoral leases; special leases; grazing licences; and pastoral occupation licences. About 48% of the South Island high country is held under Crown pastoral leases specified by the Land Act 1948. The leases allow the use of the land primarily for pastoral purposes and have perpetual rights of renewal. The RCD Applicant Group emphasises the interests of the Crown in its Response to Review Reports, Part Two: | |
| "Although leasees are responsible for rabbit control on Crown leasehold lands, the inadequacy of the current range of control tools has led to overgrazing and loss of vegetation and soil. Therefore: | |
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Of critical importance in any pest management strategy for rabbits is the difficulty of assessing the benefits and costs of control strategies and deciding who should pay. For example, on undeveloped high and extremely highly rabbit-prone land in Otago and the Mackenzie basin, the costs of current "best practise" rabbit control exceed the present income from the land. Individual owners have different proportions of such uneconomic land and questions remain unanswered as to who should pay to control rabbits on these lands, which also have conservation, environmental and social values. If farmers are forced to leave their farms who will care for the land and meet the costs of rabbit control and restitution of the land? See also section 2.1 and the discussion: retirement of land from grazing.
2.3 Severity and distribution of any impact on native flora and fauna.
Of the existing control measures for rabbits, poisoning has the greatest potential for affecting native animals. Direct losses of birds and invertebrates can occur but data does not exist which quantifies its frequency or ecological importance. Secondary losses of predators through the consumption of poisoned rabbits can occur but predator losses are only about 8%.
Existing control measures can have severe effects on rabbits (1080 operations can kill 95%), inducing predators to focus more on available native species. However, the timing, locality and extent of these operations is known in advance. To a degree, then, predatory outcomes can be predicted and mitigating actions on behalf of native species can be planned and executed. However, it is only recently that DoC has undertaken limited predator control work in conjunction with rabbit control measures.
See section 5.2.2 for a discussion on prey switching of predators.
Control of predators
Declines of several native species are ongoing and predation is a major cause. Costs of trapping for predator control to achieve conservation goals are high and the benefits localised. Poisoning methods are far more cost-effective but need urgent research to improve efficacy and check environmental safety risks.
Effects on flora
The effects on flora of a reduction in rabbit numbers following successful rabbit control are expected to be the same regardless of the control tool. These impacts are discussed in section 5.2.
2.4 Humaneness.
See section 3.3.
2.5 The health and social well-being of people.
It is very frustrating for some farmers attempting to control rabbits especially when there is a rapid recovery in numbers and when the cost of control exceeds the return on the land. It is also very distressing to see the impact on production and the degradation of the land associated with high rabbit densities.
Farming families in the highly rabbit-prone areas are known in some cases to be under severe financial stress and it is believed that this would be reduced significantly if they could control rabbits cost-effectively.
The direct pressures upon farming families caused by rabbits are significant, and include: increased financial costs and risks; decreased ability to budget accurately due to the volatile nature of rabbit populations, adding to an already difficult economic regime for farms; high work loads, in carrying out rabbit control; loss of family time caused by one of the family having to be out at night on rabbit control; increased risk of accident from working with vehicles and firearms in rough terrain.
Submitters claim that the social cost of rabbits is traumatic and the stress on individuals and families is "devastating" and "soul destroying". The effects on production and profitability impact on the lives of farmers, as well as on down stream industries, employment and rural communities.
Poor farm returns means fewer farming families and reduced farm labour, with effects on schools, social services and organisations that are noted as already marginal in many rural areas.
2.6 The use and enjoyment of the public of lands and waters to which they have right of access.
No comments have been made in the Application or by submitters.
Conclusion
| I agree with the Application conclusion on page 42: | |
| "To counter the rabbit problem, New Zealand has made use of a range of control methods. A combination of many of these methods - notably poisoning and shooting, trapping or fumigating - has generally succeeded in lowering rabbit numbers at least temporarily, and Regional Pest Management Strategies ensure the continuation of a planned and integrated approach to control." | |
While current methods of rabbit control are effective they have a high cost in relation to the commodity prices recovered from rabbit affected types of land. For properties with medium to extreme rabbit proneness the cost of rabbit control is often greater than the financial returns that control brings. Rabbit control is therefore not financially sustainable so rabbit numbers are increasing together with the resultant degradation of the land in the worst areas.
In addition, the present reliance on the use of 1080 is a serious weakness in the current approach to pest management given the potential market risks and technical limitations associated with its widespread use.
I therefore find that there is a case for an alternative rabbit control tool.
Contact for Enquiries
Manager, Strategic Science Team
MAF Biosecurity New Zealand
PO Box 2526
Wellington
NEW ZEALAND
Phone: +64 4 894 0115
Fax: +64 4 894 0731
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