ADDITIONAL IMPACT ASSESSMENT AND COST BENEFIT ANALYSIS FOR THE GREATER WELLINGTON REGIONAL PEST MANAGEMENT PLAN 1. PURPOSE

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1 ADDITIONAL IMPACT ASSESSMENT AND COST BENEFIT ANALYSIS FOR THE GREATER WELLINGTON REGIONAL PEST MANAGEMENT PLAN 1. PURPOSE This report provides an impact assessment and cost benefit analysis for the inclusion of wilding conifer and feral deer in the Regional Pest Management Plan (RPMP). It is prepared in accordance with the requirements of the Biosecurity Act 1993 and the related National Policy Direction for Pest Management 2015 (NPD). 2. PROPOSED PROGRESSIVE CONTAINMENT PROGRAMME PESTS 2.1 Wilding conifers European larch, Douglas fir, pine species (Larix decidua, Pseudotsuga menziesii, Pinus spp.) Description Wilding conifers are any introduced conifer tree, including (but not limited to) any of the species listed in Table 1, established by natural means, unless it is located within a forest plantation, and does not create any greater risk of wilding conifer spread to adjacent or nearby land than the forest plantation that it is a part of. For the purposes of this definition, a forest plantation is an area of 1 hectare or more of predominantly planted trees. Table 1. Wilding conifer species COMMON NAME European larch Douglas fir SCIENTIFIC NAME Larix decidua Pseudotsuga menziesii Pine species Bishops pine Contorta or lodgepole pine Corsican pine Dwarf mountain pine Pinus muricata Pinus contorta Pinus nigra Pinus mugo

2 Maritime pine Mountain pine Ponderosa pine Radiata Pine Scots pine Pinus pinaster Pinus unicinata Pinus ponderosa Pinus radiata Pinus sylvestris Wilding conifers are introduced conifers that have mainly established naturally as a result of natural seed spread. This process has been exacerbated by landowners failing to take action when wilding conifers first occur, and much of the ongoing wilding conifer spread in New Zealand is generated from existing areas of reproducing wilding conifers. Much of the initial wilding conifer spread originated from a range of sources, particularly historic or legacy plantings, such as Crown plantings for erosion control (as in our region) and research; long-established shelterbelts and amenity plantings on private and pastoral lease land; and in some locations, from woodlots and forest plantations. Wilding conifers are produced by many different introduced conifer species. Ten conifer species are recognised as currently contributing most to the wilding conifer problem in New Zealand. While some of these species now have little or no commercial value and are no longer planted, or much less frequently planted than in the past, several of these species, particularly Radiata pine (Pinus radiata) and Douglas fir (Pseudostuga menziesii), are highly valuable commercially grown species that contribute significantly to forestry exports. a. Pest status, attributes and distribution Status in New Zealand With the development of the Nation Wilding Conifer Strategy , a number of regional Councils have wilding conifers listed as pests in RPMPs. Relevant biology Attribute Form Habitat Regional distribution Competitive ability Description Various forms from evergreen stunted growth forms (eg, contorta pine) to deciduous (European larch) and tall specimen trees (eg, various pine species and Douglas fir) Range of habitats from open areas to regenerating bush, but most destructive in the high country at alpine and sub-alpine and/or upper bush margin zone. Limited known distribution in Eastern Rimutaka range (Pakuratahi KNE) and some urban and peri-urban problem sites Wilding conifers aggressive colonizing characteristics aid their ability to displace low-level plant communities, especially native grasslands, and create forests. Also Douglas fir is able to spread into shrublands, regenerating native forest and mature forest where there are canopy gaps and a relatively sparse understory.

3 Reproductive ability Resistance to control Benefits Very easily dispersed through wind-blown seeds A range of effective control methods exist. Control of trees on often steep terrain pose whole raft of serious health and safety issues Minimal, some landowners could have seen wilding conifers as a resource. Majority of public and landowners see them as a threat to production and environmental values. Control programme under the RPMS Wilding conifers are managed under site led Key Native Ecosystems, Reserves and Forest Health programmes under the Regional Pest Management Strategy Current situation Wilding conifers has been identified as being in the Wellington Region. Due to the limited known infestation, the progressive containment programme is proposed as: The species is limited in distribution in the Wellington Region. b. Impact assessment Land use/habitats Land use type Current land use infested Potential land use infested Pest significant problem on this land type Dairy - Low No Sheep and beef - Low No Forestry - - No Horticulture - - No Native bush/conservation Low Medium Yes Coastal - - No Estuarine and marine - - No Freshwater/wetland - - No Urban/non productive - Low No

4 Water bodies occupied Water Body Type Current water body infested Potential water body infested Lakes - - Rivers & Streams - - Wetlands - - Ponds & dams - - Drains & canals - - Troughs - - High = Most infested/preferred Low = Less infested/preferred How is it a problem? Category Current Potential Comment Source Production Dairy - - Description Sheep and beef - - Forestry - - Horticulture - - Tourism - - International trade - - Other - - Environment Soil resources - Low Alters decomposition rates and nutrient cycling. Can raise soil levels through sedimentation. Water quality Low Moderate Can cause lowering of the water table. Threatened species Low High Significant threat to indigenous biodiversity as it can form dense stands of monoculture

5 replacing alpine and sub alpine ecosystems. Species diversity High Dense stands compete with indigenous species and prevent native recruitment. Social/cultural Human health - - Recreation - Moderate Forms dense and impenetrable stands that obstruct access and changes general landscape feel of the area. Māori culture Low Can impede or restrict access to cultural sites Options to respond to Wilding conifers 1. Do nothing: In this scenario, no control of Wilding conifers is undertaken, and the assumption is made that the species continues to establish in new areas and no attempt is made to control infestations. 2. Progressive containment: In which the intermediate outcome for the programme is to contain or reduce the geographic distribution of the subject, or an organism being spread by the subject, to an area over time. Level of analysis In relation to the NPD considerations (section 6(1) outlines four criteria) a low-level analysis was deemed appropriate for Wilding conifers. c. Cost-benefit analysis Benefits of each option Benefit Option No regional intervention Progressive containment To reduce the geographic distribution or extent (do-nothing approach) Low limited to alpine and subalpine terrain in the Medium High as wilding pines can have significant adverse impact on land production, landscape,

6 of Wilding Conifers to protect the Wellington Region s indigenous environmental values, specifically alpine and subalpine habitat biodiversity. Wellington region. environmental and native biodiversity values. Also wilding conifer control reduces risk to Māori losing access wahi tapu sites and loss of taonga species. Costs of each option Programme costs No regional intervention (do-nothing approach) Annual cost (excl GST) Option Progressive containment Annual cost (excl GST) Council costs - $20,000 Control Surveillance Administration Education/awareness Land occupier costs - - Total ($) - $20,000 Costs of effects on values Medium very few known sites and limited natural habitats that would be adversely affected by the spread of wilding conifers Low - a progressive containment programme would reduce the impact on the environment for a modest cost of control. CBA assumptions and inputs Pest assumptions Values Programme assumptions Values Current area infested: 800ha Proposed programme: Progressive containment Maximum potential area infested: 5,000ha Proposed annual expenditure by Council: $20,000 Time to reach maximum extent: 75 (5) Repeated inspections and works required: Inspect and control by service delivery annually.

7 Current impacts ($): Unknown Discount rate: 4% d. Risks to success Risk that each option will not achieve the NPD objective 6(2)(g) Option No regional intervention Progressive containment (do-nothing approach) Risk type Outcome risk (technical and operational risks) Medium - infestations would increase. Voluntary control by landowners likely to have little impact. Low some risk if using chemical control due to the potential for nontarget damage. Regulatory Risk Low Low some risk if using chemical control but known infestations are not in an area easily accessible to public. Legal risk Low Low Socio-political risk Medium if left uncontrolled it could extend its range and become a nuisance to the public of the region. Under a do-nothing approach there would be a moderate to high risk of public and political criticism of Greater Wellington for not being more proactive over wilding conifer management, as it is done in neighbouring regions. Medium high - if no prevention, this plant could expand its range which could become a nuisance and be noticed by the general public in future. Other risks - - e. Who should pay? Matters for consideration in allocating costs for proposed Wilding Conifer plan Legislative rights and responsibilities Management objectives Stage of infestation None known. Progressive containment. Very few known infestations and all are under control

8 Most effective control agents Urgency Efficiency and effectiveness Practicality of targeting beneficiaries Practicality of targeting exacerbators Administrative efficiency Security Fairness Reasonable Parties bearing indirect costs Transitional cost allocation arrangements Mechanisms available Greater Wellington control is likely to be more effective due to the limited number of known sites and the potential of infestation. Moderate Greater Wellington owns or administers land with known infestations. Greater Wellington control is the most effective option The main beneficiaries are the wider community for biodiversity benefits and this group can be readily targeted through the General Rate. Exacerbators other than Greater Wellington are currently unknown. General rate is highly efficient for addressing community benefits related to biodiversity. Rating mechanisms are generally secure. Fair as only known infestations are on the publically owned land Yes. None known. None required. General rate is the most readily available mechanism. Levies are expensive to establish and administer. Beneficiaries and exacerbators Group Beneficiary Exacerbator Change behaviour Benefits exceed costs Control cost effectively Land occupiers Regional community Minor Minor Yes Yes Yes Major Major No Yes No Proposed allocation of costs The proposed programme costs are to be 100% Council costs, allocated across the various rating districts used in the Wellington Region under the Local Government (Rating) Act 2002.

9 f. Preferred option Progressive containment is the preferred option and is realistic given the distribution of the species. Greater Wellington will undertake direct control (through its service delivery programme) of Wilding conifers at all known sites. The control costs involved under a progressive containment programme are relatively minor compared to the benefits to the regional biodiversity and natural environments.

10 3. PROPOSED SITE-LED PROGRAMME PESTS 3.1 Feral deer (Cervus elaphus) Red deer were liberated in Wairarapa in the 1800s and were well established by early 1900s. Fallow and sika were illegally released in the Wellington region in more recent times for recreational hunting. Red deer still remain the most common species in the region. Feral deer frequent native bush, regenerated scrubland, exotic forestry and rough grassland in the region. Any deer which is not held behind effective fences or otherwise constrained, and identified in accordance with a recognised identification system, is considered to be feral by GWRC. a. Pest status, attributes and distribution Status in New Zealand Naturalised. Under the Wild Animal Control Act 1977, any deer that is not - (A) held behind effective fences or otherwise constrained; and (B) identified in accordance with an animal identification device approved under the National Animal Identification and Tracing Act 2012 or in accordance with an identification system approved under section 50 of the Biosecurity Act 1993 and approved by the Director-General for the purposes of this Act, is recognised as a wild or feral deer. Relevant biology Attribute Form Description Fallow are a small deer, with a coat that is either black, brown with spots, or occasionally, white. Adults weigh between 30 and 85kg. Red deer are a medium sized deer with a reddish brown coat and a creamy coloured rump patch. Adults weigh between 80 to 200kg. They are the largest and most common deer in the region. Sika are a small deer, chestnut coloured in summer with spots, and dark coloured in the winter, When alarmed, sika display a white rump patch, and make a piercing whistle. Adults weigh between 45 and 85kg. Habitat Generalist herbivore that browses a wide variety of plant species but often concentrates the majority of feeding on a small number of favoured species. They are able to stand on

11 two legs to reach higher vegetation, and will eat fresh leaf litter as well as live vegetation. Feral deer are able to occupy a wide variety of climates and habitat types, and are able to survive in the absence of a permanent water source. Regional distribution Competitive ability Reproductive ability Resistance to control Benefits Widespread Efficient in digestion of plant and leaf material, facilitating the use of a wide variety of plant species. Palatable bush plant species such as pate, broadleaf, three-finger, lancewood, and hen and chicken fern can be all but removed from the ground tier. Browsing reduces vegetation cover and density and causes the loss of plant species richness and altered community composition in favour of unpalatable species. Pest plant invasion can occur under these circumstances. Deer also damage vegetation planted on land retired for soil conservation purposes and newly planted or young trees in exotic forests. Polygynous mating system (one male with a group of females) with high reproductive success. One offspring produced per year. Juveniles stay with the mother for about 6 months. No natural predators in New Zealand. Controlled by shooting and high-quality fencing. High recreational hunting values and also limited wild meat exports Control programme under the RPMS Feral deer are controlled under site led Key Native Ecosystems, Reserves and Forest Health programmes under the Regional Pest Management Strategy Current situation Feral deer are widespread throughout the region, however high numbers are localised. Control programmes are maintained by service delivery in several Key Native Ecosystem sites in the region by Greater Wellington and hunted by the recreational and professional hunters.

12 b. Impact assessment Land use/habitat types Land use type Current land use infested Potential land use infested Pest significant problem on this land type Dairy - Low No Sheep and beef Low Moderate Yes Forestry Low Moderate Yes Horticulture Low Low No Native bush / conservation High High Yes Coastal Low High No Estuarine and marine - - No Freshwater / wetland - - No Urban / non productive Low Low No How is it a problem? Category Current Potential Comment Production Dairy - Low Competes with stock for pasture and reduces pasture productivity. May spread livestock diseases. Sheep and beef Low Moderate Removal of vegetation through browsing and trampling can cause soil erosion, particularly in the eastern hill country. Forestry Low Moderate Can cause severe damage to young trees in plantation forests by trampling seedlings, browsing young trees and stripping bark from older trees. Horticulture - Low Can cause damage to fruit trees and crops.

13 Tourism - - Resource - can be seen as a tourist attraction, also hunting tourism International trade - - Resource - modest exports of wild venison to overseas markets Environment Soil resources Low Moderate Removal of vegetation through browsing and trampling can cause erosion. Water quality Low Moderate Erosion of soil can lead to increased sedimentation in waterways. Threatened species Low Moderate Eats a wide variety of plant species and can eliminate preferred (palatable) species, leading to changes in plant species composition, and preventing forest regeneration and succession. Species diversity High Eats a wide variety of plant species and can eliminate preferred (palatable) species, leading to changes in plant species composition, and preventing forest regeneration and succession. Social / cultural Human health Low Damages and eliminates palatable native plant species and alters structure of native forest, which can affect recreational experiences. Viewed as a recreational resource by hunters. Recreation Low Destroys native forests and damages peri-urban gardens. Māori culture Moderate Destroys native forests and eats culturally important plants. Options to respond 1. Do nothing: In this scenario, no control of feral deer is undertaken, and the assumption is made that the species continues to establish and no attempt is made to control the population. 2. Site-led: In which the intermediate outcome for the programme is that the subject, or an organism being spread by the subject, that is capable of causing damage to a place is excluded or eradicated from that place, or is contained, reduced or controlled within the place to an extent that protects the values of that place.

14 Level of analysis In relation to the NPD considerations (section 6(1) outlines four criteria) a low-level analysis was deemed appropriate for feral deer. c. Cost-benefit analysis Benefits of each option Benefit Option Protect the cultural and economic values of KNE areas and on TA reserves in the region. No regional intervention (donothing approach) Council avoids the costs of an intervention approach. Site-led Provides for a rule for the control of feral deer. Mitigates adverse impacts of feral deer in high value native biodiversity areas by maintaining low deer numbers. Costs of each option Programme Costs Option Council costs Control Surveillance Administration Education / awareness No regional intervention (donothing approach) Annual cost (excl GST) $5,000 mostly staff time responding to public enquiries Site-led Annual cost (excl GST) $13,500 contact management and control work. $5,000 mostly staff time responding to public enquiries Land occupier costs $- $- Total ($) $5,000 $18,500 Costs of effects on values High - Due to feral deer having a large home range, no respect for boundaries, and can reinvade areas from long distances, control efforts can be short lived if constant control is not maintained. Feral deer occur throughout some rural and semi- Low - Costs to values are reduced. Ongoing costs of a control programme.

15 rural areas of the Wellington Region. Environmental impacts are recognised as being severe where no control is undertaken. d. Risks to success Risk that each option will not achieve the NPD objective 6(2)(g) Options Risk type Outcome Risk (Technical and operational risks) No regional intervention (do-nothing approach) Medium Control of individuals in the wild can be difficult due to the animal intelligence and wariness; access to all land types, and therefore may not be successfully implemented by the public in the absence of regionally coordinated management by Council. Inadequately contained farmed deer and illegal releases represent an ongoing source of reinvasion of high biodiversity value areas. Site-led None identified. Regulatory Risk None identified. Medium - Potential for deliberate releases to establish or supplement wild populations as a hunting resource. Legal risk None identified. None identified. Socio-political risk None identified. Medium - Valued by iwi and some sectors of the public as a cultural, recreational and/or food provisioning resource. Other risks None identified. None identified. e. Who should pay? Matters for consideration in allocating costs for proposed feral deer plan

16 Legislative rights and responsibilities Management objectives Stage of infestation Most effective control agents Urgency Efficiency and effectiveness Practicality of targeting beneficiaries Practicality of targeting exacerbators Administrative efficiency Security Fairness Reasonable Parties bearing indirect costs Transitional cost allocation arrangements Mechanisms available Responsibilities under the Wild Animal Control Act 1977 Site-led. Established throughout the region. Greater Wellington to undertake direct control by service delivery in Key Native Ecosystems and in actively managed Territorial Authority reserves. Low. General rate is highly efficient for addressing community benefits related to biodiversity. Individual beneficiaries cannot be easily targeted at a regional level other than through a levy. The majority of benefits are for the public of the region as a common good through maintained or improved native biodiversity values. Wider beneficiaries can be targeted through general rate. Feral deer are highly mobile so difficult to target exacerbators. General rate is highly efficient where common good and wider public benefits are addressed. Rating mechanisms are generally secure. Moderate. Wider community covering costs for a pest which may not currently affect them directly. Given the moderate funding requirements and difficulty of alternative approaches the general rate is a reasonable approach. Hunters experience some loss of value associated with perceived reduced hunting opportunity. None required. General rate is the most readily available mechanisms. Levies are expensive to establish and administer. Beneficiaries and exacerbators Group Beneficiary Exacerbator Change behaviour Benefits exceed costs Control cost effectively

17 Land occupiers (Crown and Private) Regional Community Major Major Yes Yes Yes Major - No Yes Yes Proposed allocation of costs The proposed programme will be funded through the general rate allocated across the various rating districts used in the Wellington Region under the Local Government (Rating) Act 2002, and cost recovery. f. Preferred option Site-led Key Native Ecosystem and TA Reserves programme is the preferred option and is realistic given the region wide distribution of feral deer. Greater Wellington will undertake direct control (through its service delivery programme) of feral deer on selected KNE sites. The control costs involved under site-led programme are relatively minor compared to the benefits to the regional biodiversity and natural environments.