ENVIRONMENTAL RISK MANAGEMENT AUTHORITY DECISION Date signed:17 April 2007

Application code: NOR06005 Application category: Import for Release or Release from Containment any New Organism under the Hazardous Substances and New Organisms (HSNO) Act 1996 Applicant: The Californian Thistle Action Group Applicant contact: Richard Hill Purpose: The Californian Thistle Action Group (CalTAG) seek approval to import for release a , Ceratapion onopordi (Brentidae) and a , rubiginosa (Chrysomelidae), for the biological control of the weed Californian thistle (Cirsium arvense) under section 34(1)(a) of the Hazardous Substances and New Organisms Act 1996 (the HSNO Act). Date application received: 10 November 2006 Consideration date: 2 March 2007 Considered by: Committee of the Authority

1 Summary of Decision

1.1 The application to import for release Ceratapion onopordi (Brentidae) and Cassida rubiginosa (Chrysomelidae), for the biological control of the weed Californian thistle (Cirsium arvense) is approved, without controls, having being considered in accordance with the relevant provisions of the Hazardous Substances and New Organisms (HSNO) Act 1996 (the Act) and the HSNO (Methodology) Order 1998 (the Methodology).

2 Application Process and Associated Legislative Criteria

Application receipt

2.1 The application was lodged pursuant to section 34(1)(a) of the Act. The application was formally received and verified as containing sufficient information on 10 November 2006. As required under section 53(1)(b) of the Act, the application was publicly notified. Notification of receipt and a request for submissions were sent to the Minister for the Environment, Department of Conservation (DOC), the Ministry of Agriculture and Forestry (MAF), other government departments and agencies, local authorities, Iwi, Universities, Crown Research Institutes, industry groups, community groups, interest groups and public individuals on 10 November 2006 and notification was placed on the ERMA New Zealand website on the same day. Further notification was made in The New Zealand Herald, The Dominion Post, The Press and the Otago Daily Times on 13 November 2006. Public submissions closed on 19 January 2007.

2.2 Fifty eight submissions were received, of which four submitters indicated a wish to be heard; two in support (No. 8831 and 7804) and two opposed (No. 8804 and 8832). Subsequent correspondence addressed all concerns and as a result, all submitters were satisfied that their concerns were considered within the Evaluation and Review (E&R) report and withdrew their requests to be heard. As a result, the Authority did not consider a hearing necessary and thus no hearing was held for this application. Summary of submissions can be found in Appendix 2 of the E&R report. Information available for consideration

2.3 The documents available for the consideration of the application were:

Application NOR06005 including:

Appendix A: Community consultation;

Appendix B: The biology and weed status of Californian thistle in New Zealand;

Appendix C: Host specificity of Cassida rubiginosa Müll. (Coleoptera: Chrysomelidae) and Apion onopordi Kirby (Coleoptera: Apionidae), potential biological control agents for Californian thistle (Cirsium arvense) in New Zealand. Landcare research contract report: LC0506/096 unpublished (2006);

Relevant references.

Public submissions

Evaluation and Review (E&R) report prepared by ERMA New Zealand:

The E&R report was prepared by the Agency to assist and support decision-making. Correspondence from external experts are included in the appendices of the E&R report.

Decision-making committee

2.4 The application was considered by a Committee of the Authority comprising the following members: Dr Max Suckling (Chair), Helen Atkins and Dr Kieran Elborough.

Sequence of the consideration 2.5 The consideration of the application took place on 02 March 2007. The application was considered under section 38 and determined in accordance with section 38(1)(a) of the

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HSNO Act. Consideration of the application followed the relevant provisions of the Act and the Methodology, as specified in more detail below. Unless otherwise stated, in this decision, references to Clause numbers refer to Clauses of the Methodology and references to section numbers refer to sections of the Act.

3 Submissions 3.1 The Committee agreed with the summary of submissions prepared by the project team (Appendix 2 of the E&R Report). When considering the potential beneficial and adverse effects of these organisms the Committee took into consideration all significant issues raised in the submissions.

3.2 The Committee considered the Department of Conservation’s submission regarding insufficient host range testing for Cassida rubiginosa and concluded that the host range testing of surrogates representing native species provided sufficient evidence to ensure that species outside of the Cardueae tribe were not at risk (see section 5.3.3 of the E&R report for further discussion on the use of surrogates).

4 Purpose of the Application 4.1 Californian thistle occurs throughout New Zealand and is one of the most serious and persistent weed problems of pastoral and cropping farms. The Californian Thistle Action Group (CalTAG) seek approval to import for release a weevil, Ceratapion onopordi (Brentidae) and a beetle, Cassida rubiginosa (Chrysomelidae), for the biological control of the weed Californian thistle (Cirsium arvense). Efficacy of the Biological Control Agents

4.2 The Committee considered that beneficial effects could only be realised if Ceratapion onopordi and/or Cassida rubiginosa were successful in establishing a self-sustaining population and had an adverse effect on Californian thistle (sections 5.1 and 5.2. of the E&R report).

3.5 The Committee noted that the identification and assessment of effects presented in the E&R report is based on assumptions within the application which represent an ‘expected scenario’. Under this scenario, following the initial release, benefits are predicted to occur within 10 years and will improve with further distribution and establishment of the organisms (section 7.2 of the E&R report).

5 Identification and Assessment of Potentially Significant Adverse Effects (Risks and Costs) and Benefits

Methodology 5.1 The Committee reviewed the identification and assessment of possible effects to: the environment, human health, Māori culture and traditions, society and the community and the market economy as presented in the E&R report. The assessment of potentially

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significant adverse effects was structured according to Clause 12 of the Methodology, including the magnitude of adverse effects and the likelihood of occurrence, options for managing risks, and uncertainty bounds on the information. In assessing costs and benefits the Authority considered whether or not these costs and benefits are monetary, their magnitude or expected value (including uncertainty) and the distribution of costs and benefits over time and affected groups in the community (Clause 13). Risk characteristics were considered in terms of Clause 33 of the Methodology. The degree of uncertainty attached to the evidence was taken into account, as required by Clauses 25, 29, 30 and 32.

5.2 The Committee rated the materiality and significance of uncertainty of each magnitude and the likelihood associated with each potentially significant cost and benefit (Clause 29).

5.3 The Committee considered the information provided relevant and appropriate to the scale and significance of the risks, costs and benefits associated with the application (Clause 8).

5.4 For each potentially significant effect, the level of risk or benefit was calculated using the qualitative scales from Appendix 1 of this report.

5.5 The Committee reviewed all of the potential effects identified by the applicant, submitters and the project team. The Committee identified additional effects (see section 5.38) and agreed that all potential effects had been identified.

5.6 The Committee agreed with the project team’s assessment, in the E&R report (Appendix 1), that some of the potential effects identified were not significant and therefore required no further consideration.

5.7 The Committee considered all of the potentially significant effects assessed in the E&R report. The Committee then assigned a risk, cost or benefit level (between A and F, as defined in Appendix 1 of this report) to each potentially significant effect.

5.8 The Committee confirmed that those effects rated as A or B are considered negligible. Host Specificity and Impacts on Non-Target

5.9 The assessment of potential risks associated with the release of biological control agents relies on robust experiments describing the organism’s host range. This evidence can then be used to determine the extent to which native and/or valued species are at risk.

5.10 Confirmation of adequate host range testing was provided by taxonomist Dr Ilse Breitwieser an expert on the family , to which Californian thistle belongs. The Committee noted that the host range testing was not reviewed by an external entomologist but agreed that this was not necessary.

5.11 The Committee considered the information from host-range testing experiments conducted both overseas and in New Zealand. It was noted that laboratory tests can overestimate a host’s natural range (Gourlay and Hill, 2006). Experimental testing indicated that the host range of Cassida rubiginosa is slightly wider than Ceratapion onopordi

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but still within the thistle tribe (Cardueae). The Committee concluded that the testing was robust and provided evidence that Cassida rubiginosa and Ceratapion onopordi show a high degree of host specificity and therefore, would be unlikely to adversely affect species outside the tribe Cardueae. The Committee noted that there are no New Zealand native species within this tribe.

5.12 Further host range testing was conducted on related tribes containing native species, surrogates representing native species and culturally significant species, ie puha (exotic Sonchus oleraceus). Results indicated minor feeding on S. oleraceus but showed that no larval development occurred on either puha species (S. oleraceus and S. kirkii). The Committee considers that the minor feeding observed is reversible and unlikely to significantly affect puha.

5.13 The Committee noted that the host range testing indicates that Ceratapion onopordi and Cassida rubiginosa pose a low level of risk to non-target valued plants (see sections 5.38 and 5.44 of this report).

5.14 The Committee noted that there are valued and potentially valued species within the tribe Cardueae that fall within the host range of the proposed biological control agents, eg variegated thistle (), safflower (Carthamus tinctoriusi), cornflower (Centaurea cyanus) and globe (Cynara solymus). The Committee also noted that they had no information on how significant these species were as crops or home-grown food sources and therefore noted uncertainty about the magnitude of effects. The Environment Adverse and Beneficial Effects 5.15 The Committee considered that the beneficial effects to the environment outlined in the E&R report were not significant as thistle species do not significantly impinge on native environments.

5.16 Adverse effect 1: That Ceratapion onopordi and Cassida rubiginosa provide additional resources increasing the abundance of predaceous and parasitoid . Consequently, populations of native/valued insects are reduced.

5.17 The Committee reviewed the information provided in the E&R report and the comments from expert reviewers and considered that the addition of these species would not significantly add to the prey biomass of pastoral ecosystems. The Committee thus considered that at worst there would be a minimal effect on the food web and the likelihood of that effect is improbable, and that the associated level of risk is A (negligible).

5.18 Adverse effect 2: Reduction in populations of native/valued herbivores through increased competition by Ceratapion onopordi and Cassida rubiginosa.

5.19 The Committee noted that there is no evidence to suggest that any native species rely exclusively on Californian thistle for their survival. The Committee considered at worst any effects on native/valued herbivores to be minimal and the likelihood of that effect highly improbable, and that the associated level of adverse effect is A (negligible).

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5.20 Adverse effect 3: Damage to the ecosystem from the release of a more damaging biological control agent or unwanted associated organism (for further information see the market economy sections 5.46 and 5.49 of this report).

5.21 The Committee acknowledged the applicant’s intentions to keep both organisms in containment in order to confirm their identification and to eliminate any associated organisms (for further information on the quarantine procedures see section 7.4.11- 7.4.14 of the E&R report). The Committee considered that the effect of releasing an incorrectly identified organism or an associated organism to be moderate and the likelihood highly improbable, and the associated level of adverse effect is B (negligible).

5.22 Adverse effect 4: Damage to native flora from non-target feeding.

5.23 The Committee considered that any damage to valued species (not native) is an effect relevant to the market economy and has addressed those effects separately (see section 5.44). Having reviewed the potential for non target effects (see above sections 5.9-5.14) the Committee considered that at worst the effect of non target feeding on native plants is minimal the likelihood highly improbable, and the associated level of adverse effect A (negligible).

5.24 Adverse effect 5: Damage to non-target host species via the transmission of a European rust fungus Puccinia punctiformis.

5.25 The Committee identified this effect as not significant as Puccinia punctiformis is host specific to thistles, is not an inseparable organism and already occurs in New Zealand.

5.26 In addition, both biological control agents will be reared through at least one generation in a quarantine containment facility to eliminate any fungal contamination.

Human Health and Safety 5.27 The Committee considered that there were no significant adverse or beneficial effects to human health and safety. Thus no further assessment was warranted.

Māori Culture and Traditions

Consultation 5.28 The Committee were satisfied that national consultation had been conducted in accordance with ERMA New Zealand guidelines.

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Adverse Effects 5.29 Adverse effect 1: Potential impacts on kaitiakitanga from adverse effects to puha.

Ceratapion onopordi

5.30 The Committee reviewed the results from the host range testing and concluded that no adults attacked or could complete development on any puha (Sonchus spp.). Consequently the Committee considered any risks negligible and thus no further consideration of these effects was necessary.

Cassida rubiginosa

5.31 The Committee considered evidence in the host range testing that indicated low incidences of Cassida rubiginosa feeding on Sonchus oleraceus (exotic puha). The Committee recognised the cultural significance of taonga species and the associated range of risk adopted in the E&R report. It is noted that Cassida rubiginosa is predicted to attack S. oleraceus at low levels. However, no larval development occurred on either puha species (S. oleraceus or S. kirkii), suggesting that puha could not support populations of Cassida rubiginosa (Gourlay and Hill, 2006). The Committee considered that any minor feeding was, reversible and unlikely to debilitate S. oleraceus.

5.32 The Committee concluded that at worst the adverse effects on puha to be moderate and the likelihood highly improbable, and allocated a level of adverse effect to be B (negligible).

5.33 Adverse effect 2: Potential impacts on kaitiakitanga from adverse impacts on mahinga kai.

Ceratapion onopordi

5.34 The Committee reviewed results from the host range testing and concluded that no adults attacked or could complete development on any Sonchus spp. (puha). Consequently the Committee considered any risks negligible and thus no further consideration of these effects was necessary.

Cassida rubiginosa

5.35 The Committee considered evidence in the host range testing that indicated low incidences of Cassida rubiginosa feeding on Sonchus oleraceus (exotic puha). The Committee recognised the cultural significance of taonga species and the associated range of risk adopted in the E&R report. It is noted that Cassida rubiginosa is predicted to attack S. oleraceus at low levels. However, no larval development occurred on either puha species (S. oleraceus or S. kirkii), suggesting that puha could not support populations of Cassida rubiginosa (Gourlay and Hill, 2006). The Committee considered that any minor feeding was, reversible and unlikely to debilitate S. oleraceus.

5.36 The Committee concluded that at worst the adverse effects on puha to be moderate and the likelihood highly improbable, and allocated a level of adverse effect to be B (negligible).

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Beneficial Effects

5.37 No specific kaitiaki and/or Iwi/Māori cultural benefits to mauri were identified by the Committee. Society and the Community

5.38 The Committee noted that adverse and beneficial effects on society and the community were not considered in the E&R report for home grown ornamentals and valued food species that fall within the biological control agents’ host range. The Committee considered these effects and incorporated them into the decision. Adverse effects

5.39 Adverse effect 1: That the introduction of the proposed biological control agents would cause adverse effects to garden ornamentals or garden plants grown for food values.

5.40 The Committee reviewed the results from the host range testing and concluded that certain garden ornamentals and valued food plants could become hosts for the proposed biological control agents, ie cornflower, safflower and globe artichoke.

5.41 The Committee noted that home gardeners would be unlikely to spray their plants and instead either tolerate the damage caused by the biological control agents or cease growing these species. Also noted was the lack of information and therefore uncertainty on the distribution of these species.

5.42 The Committee noted that low level effects on garden plants will be localised and reversible. Therefore, the Committee considered that any effect to ornamentals or food species to be at worst minor, the likelihood improbable, and allocated a level of adverse effect to be B (negligible).

Beneficial effects 5.43 The Committee considered that there were no potentially significant beneficial effects to society and the community and no further assessment was made.

The Market Economy

5.44 The Committee noted that there was little public or commercial interest in this application indicated by the relatively low number of submissions. The Committee considered the magnitude of any adverse effects on the market economy to be based on limited information about the nature and state of the commercial market of safflower, variegated thistle (relevant because of the essential oils that can be obtained from this ) and globe artichoke. Thus, a conservative approach was adopted.

5.45 The Committee concluded that the commercial impact could be assumed to be relatively small ($10,000 annually nation wide). However, a low level of attack on these plants is predicted with the introduction of both biological control agents (Gourlay, 2003) and is

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likely to affect commercial growers. The Committee noted that Ceratapion onopordi and Cassida rubiginosa occur in sympatry in where they are not considered principal pests of these crops. However, this may be a consequence of population constraints due to an increased abundance of predators and parasitoides that do not occur in New Zealand. Conversely, the Committee noted that Ceratapion onopordi and Cassida rubiginosa could, if required, be killed by existing pesticide programs. On making an assessment of adverse effects the Committee also considered the predicted extent of damage caused by Ceratapion onopordi and Cassida rubiginosa. That is, whether the whole crop will be damaged versus cosmetic damage and whether the grower would likely change crops.

5.46 Of some concern to the Committee was the potential for accidental introduction of a closely related species Cassida deflorata which is known as a pest of globe artichoke. This concern arises because Cassida deflorata is morphologically similar to Cassida rubiginosa and thus could be mis-identified. Ensuring the correct identification of the imported species is the responsibility of MAF and will be addressed within the associated Import Health Standard (IHS). Adverse effects

Cassida rubiginosa and Ceratapion onopordi

5.47 Adverse effect 1: That the biological control agents would cause adverse effects to the market economy of valued crops, ie, safflower, variegated thistle and globe artichoke.

5.48 The Committee considered a minimal magnitude of effect (best case scenario) likely and allocated an associated level of risk D (non-negligible). In addition, the Committee considered a conservative approach that a minor magnitude of effect (worst case scenario) is improbable and allocated an associated level of risk B (negligible).

Cassida rubiginosa

5.49 Adverse effect 2: That the wrong species (Cassida deflorata) is introduced and causes adverse effects to the market economy of globe .

5.50 Of concern to the Committee was the accidental release of C. deflorata which preferentially attacks globe artichokes. The Committee considered the magnitude of risk to globe artichokes with the knowledge of the artichoke industry. The Committee directed that MAF be alerted to address this issue in the corresponding IHS.

5.51 The Committee adopted a conservative approach as there was limited information available on this species and assigned the magnitude of effect as moderate and a likelihood of improbable and thus the level of risk C (non-negligible).

Beneficial Effects

Cassida rubiginosa and Ceratapion onopordi

5.52 Beneficial effect 1: That the biological control of thistles would facilitate improved farm production and earnings.

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5.53 Approximately $4,000 (actual figure in application $3,101) per farm is lost annually on production costs attributable to Californian thistle. This loss summed across New Zealand’s 15,000 commercial farms totals more than $60 million annually. Based on a conservative approach, if only 10% of the Californian thistle problem was removed (10 years in a best case scenario) this leaves $6 million in annual thistle costs. The Committee halved this amount again as a conservative approach to any benefits to total $3 million which, according to Table 2 in the E&R report (Appendix 4: Magnitude of beneficial effect) represents a major magnitude of effect. The Committee considered that under normal operating conditions (as represented in Europe) this was likely to occur and allocated the associated level of beneficial effect as F (significant).

5.54 Beneficial effect 2: That the biological control of Californian thistle would reduce expenditure on other thistle control tactics.

5.55 Host specificity tests conclude that the proposed biological control agents are restricted to the thistle tribe Cardueae. Thus, all thistle species will potentially become hosts to Ceratapion onopordi and Cassida rubiginosa.

5.56 According to the applicant, assessments on thistle control expenditure in Otago and Southland average to approximately $50 million per annum. Based on a conservative approach, and Table 2 (Appendix: 4 of the E&R report), the Committee considered that 5% of this average ($2.5 million) represents a major magnitude of effect. The Committee concluded that this was likely to occur and had an associated level of beneficial effect F (significant).

6 Overall Evaluation of Risks, Costs and Benefits

Approach to uncertainty 6.1 Section 7 of the HSNO Act, and Clause 29 and 32 of the Methodology requires the Committee to take into account the need for caution in managing adverse and beneficial effects where there is scientific and technical uncertainty. The Committee thus used scenarios to set upper and lower bounds on the assessment of risks and the evaluation and decision was based on the higher value of the risk, ie a conservative approach. The Committee concluded that there was some uncertainty associated with the adverse and beneficial effects that were assessed as significant and that this uncertainty was incorporated via a conservative approach in the decision.

Approach to risk 6.2 When considering applications, Clause 33 of the Methodology requires the Authority to regard the extent to which the following risk characteristics exist (see below a-e). This provides guidance on how cautious or risk averse the Committee should be in weighing up risks and costs against benefits. The Committee noted that some of these risk characteristics are not particularly relevant to biological control agents as they are selected to minimise these characteristics:

a) Exposure to the risk is involuntary;

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The Committee considered that the exposure to the risk is voluntary for the farming communities that actively release the agents and involuntary for the people living in areas to which the insects may spread themselves.

b) The risk will persist over time:

Both Ceratapion onopordi and Cassida rubiginosa are managed by pesticide programmes on associated valued crops in Europe. The Committee considered that both organisms could potentially be eradicated if they become pests in New Zealand. Therefore risk is not necessarily persistent.

c) The risk is subject to uncontrollable spread and is likely to extend its effects beyond the immediate location of incidence:

Both Ceratapion onopordi and Cassida rubiginosa are likely to need human assistance to disperse (see section 5.1.2 of the E&R report). Thus the Committee considered that any spread of effects beyond the release sites would be limited.

d) The potential effects are irreversible:

Any impact on non-target valued crops, ie safflower, globe artichoke and variegated thistle, could be managed by existing pesticides. Thus the Committee consider any effects minor and reversible.

e) The risk is not known or understood by the general public and there is little experience or understanding of possible measures for managing the potential adverse effect:

If Ceratapion onopordi and Cassida rubiginosa become significant pests of valued crops, ie safflower, globe artichoke and variegated thistle, the Committee considered that they could be managed similarly to other invertebrate pests by the application of generic pesticides. Aggregation and comparison of risks, costs and benefits 6.3 A summary of the potentially significant effects, the magnitude of that effect should it occur, the likelihood of the effect being realised, the uncertainty regarding that effect and its associated level of risk or benefit, as determined by the Committee is provided in Table 1 (section 7 of this decision).

6.4 As there are two non-negligible adverse effects, Clause 27 of the Methodology applies and the Committee must take into account the extent to which the risk and any costs associated with C. rubiginosa and C. onopordi may be outweighed by the benefits.

6.5 The Committee noted that there would be a management mechanism included in MAF’s IHS to control the risks associated with importing C. deflorata.

6.6 Clause 34 sets out the process for evaluating the combined impact of risks, costs and benefits. The use of common units of measurement is not feasible due to the widely differing nature of the effects. Therefore the Committee has used a ranking approach

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based on the level of risks/costs/benefits as summarised in Table 1. The Committee considered whether the benefits to the market economy of thistle control and increased farm production outweighed the costs to the market economy of potential adverse effects on valued plants.

6.7 The Committee considered the overall beneficial effects of releasing Ceratapion onopordi and Cassida rubiginosa for the biological control of Californian thistle outweighed the adverse effects.

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7 Summary of potentially significant adverse and beneficial effects

Table 1 Potentially significant adverse effects (risks and costs) Description Magnitude Likelihood Effect Uncertainty/Comments level

The environment

Cassida rubiginosa and Ceratapion onopordi provide additional Minimal Improbable A This assessment is based resources increasing the abundance of predaceous and on a conservative scenario parasitoid insects. Consequently, populations of native/valued (see section 7.2 of the E&R insects are reduced. report)

Reduction in the populations of native/valued herbivores Minimal Highly Improbable A This assessment is based through increased competition by Ceratapion onopordi and on a conservative scenario Cassida rubiginosa. (see section 7.2 of the E&R report)

Damage to the ecosystem from the release of a more damaging Moderate Highly improbable B This assessment is based biological control agent or unwanted associated organism. on a conservative scenario (see section 7.2 of the E&R report)

Damage to native populations from non-target feeding. Minimal Highly improbable A This assessment is based on a conservative scenario

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(see section 7.2 of the E&R report)

Māori culture and traditions

Potential impacts on of Cassida rubiginosa kaitiakitanga from Moderate Highly Improbable B This assessment is based adverse effects to puha. on a conservative scenario (see section 7.2 of the E&R report)

Potential impacts of Cassida rubiginosa on kaitiakitanga from Moderate Highly Improbable B This assessment is based adverse impacts on mahinga kai. on a conservative scenario (see section 7.2 of the E&R report)

Society and community

That the introduction of the proposed biological control agents Minor Improbable B This assessment is based would cause adverse effects to garden ornamentals or garden on a conservative scenario plants grown for food values. (see section 7.2 of the E&R report)

The market economy

That the biological control agents would cause adverse effects Minimal Likely D This assessment is based to the market economy of valued crops ie safflower, variegated Minor Improbable on a conservative scenario B thistle and globe artichoke. (see section 7.2 of the E&R report)

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This assessment is based Moderate Improbable on a conservative scenario That the wrong species (Cassida deflorata) is introduced and C (see section 7.2 of the E&R causes adverse effects to the market economy of globe report) artichokes.

Potentially significant beneficial effects (benefits) Description Magnitude Likelihood Effect Uncertainty/Comments level

The market economy

Major Likely F This assessment is based That the biological control of thistles would facilitate improved on a conservative farm production and earnings. scenario (see section 7.2 of the E&R report)

That the biological control of thistles would reduce Major Likely F This assessment is based expenditure on other thistle control tactics. on a conservative scenario (see section 7.2 of the E&R report)

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8 Decision 8.1 The Committee has made its decision in accordance with section 38(1), taking into account the matters specified in section 6 and the principles stated in section 5. The Committee is satisfied that the organisms meet the minimum standards as set out in section 36 having regard to the abilities of the organisms to establish undesirable self-sustaining populations and the ease of eradication. This view is based on the conclusion that the organisms are not likely to cause any significant displacement of any native species, to cause any significant deterioration of natural habitats, to cause any significant adverse effects on human health, to cause any significant adverse effect to New Zealand's inherent genetic diversity or to cause disease, be parasitic or act as a vector for disease other than against the target thistle plants.

8.2 The Committee is satisfied that there is sufficient information to assess the potential adverse effects of the organisms.

8.3 The Committee noted that the Biosecurity Act 1993 requires adherence to the associated MAF Import Health Standard (IHS) that ensures that no undesirable associated organisms are imported with Ceratapion onopordi and Cassida rubiginosa.

8.4 The Committee noted that the purpose of release is for the formation of self- sustaining populations, and taking into account the potential for adverse effects, any such population would not be considered undesirable. However, should a self- sustaining population form and become undesirable, eradication or management with pesticides may be possible.

8.5 The Committee has considered all of the potential effects of the organisms, the ability of the organisms to establish self-sustaining populations and the ease of eradication of populations of the organisms. Overall analysis indicated that the beneficial effects of the release of the two biological control agents outweigh the adverse effects.

8.6 The application for release of Ceratapion onopordi (Brentidae) and Cassida rubiginosa (Chrysomelidae), for the biological control of the weed Californian thistle (Cirsium arvense) is thus approved, without controls.

8.7 In reaching this decision the Committee has applied the following criteria in the Methodology:

Clause 9 – equivalent of sections 5, 6 and 8; Clause 10 – equivalent of sections 36 and 37; Clause 12 – evaluation of assessment of risks; Clause 13 – evaluation of assessment of costs and benefits; Clause 15 and 16 – information from submissions; Clause 17, 18 and 19 – information from experts; Clause 20 – information produced from other bodies;

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Clause 21 – the decision accords with the requirements of the Act and regulations; Clause 22 – the evaluation of risks, costs and benefits – relevant considerations; Clause 23 – obtaining further information; Clause 24 – the use of recognised risk identification, assessment, evaluation and management techniques; Clause 25 – the evaluation of risks; Clause 27 – the extent to which the costs are outweighed by the benefits; Clause 29 and 32 – considering uncertainty; Clause 33 – the risk characteristics; and Clause 34 – the aggregation and comparison of risks, costs and benefits.

9 References Gourlay, AH 2003. Host specificity of Apion onopordi Kirby (Coleoptera: Apionidae), a potential control agent for Californian thistle (Cirsium arvense) in New Zealand. Landcare Research Report LC0304/003, unpublished.

Gourlay, AH, Hill, RL 2006. Host specificity of Cassida rubiginosa Müll. (Coleoptera: Chrysomelidae) and Apion onopordi Kirby (Coleoptera: Apionidae), potential control agents for Californian Thistle (Cirsium arvense) in New Zealand. Landcare Research Report LC0506/096, unpublished.

______Dr Kieran Elborough on behalf of Dr Max Suckling; Chairperson of the Decision- making Committee

Date: 17 April 2007 Approval codes: NOR000039 - 40

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Appendix 1:

Level of risk/benefit

Calculating the level of risk Using these qualitative descriptors for magnitude of effect and likelihood of the event occurring, an additional two-way table representing a level of risk (combined likelihood and measure of effect) can be constructed as shown in the Table below, where six levels of effect are allocated: A, B, C, D, E and F. These terms have been used to emphasise that the matrix is a device for determining which risks (benefits) require further analysis to determine their significance in the decision making process. Avoiding labels such as ‘low’, ‘medium’, and ‘high’ removes the aspect of perception of absolute levels of risk/benefit.

Calculating the level of risk/benefit Magnitude of effect Likelihood Minimal Minor Moderate Major Massive Highly improbable A A B C D Improbable A B C D E Very unlikely B C D E E Unlikely C D E E F Likely D E E F F Very likely E E F F F Extremely likely E F F F F

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