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ENHANCEMENTS OF PEST RISK ANALYSIS TECHNIQUES D2.3 A set of written indicators and a written protocol for scoring levels of impact in the EPPO PRA scheme accessed via a hyperlink in a project web page PD No. D2.3 Author(s): Johan Bremmer, Marc Kenis and Tarek Soliman Partner(s): LEI, CABI, WU Submission date: 26 July 2011 EU Framework 7 Research Project Enhancements of Pest Risk Analysis Techniques (Grant Agreement No. 212459) 1 PRATIQUE No. 212459 Deliverable number: D2.3 Date: 09/05/2017 _____________________________________________________________________ PROJECT OVERVIEW: PRATIQUE is an EC-funded 7th Framework research project designed to address the major challenges for pest risk analysis (PRA) in Europe. It has three principal objectives: (i) to assemble the datasets required to construct PRAs valid for the whole of the EU, (ii) to conduct multi-disciplinary research that enhances the techniques used in PRA and (iii) to provide a decision support scheme for PRA that is efficient and userfriendly. For further information please visit the project website or e-mail the project office using the details provided below: Email: [email protected] Internet: www.pratiqueproject.eu Authors of this report and contact details Name: Johan Bremmer Partner: LEI E-mail: [email protected] Name: Marc Kenis Partner: CABI E-mail: [email protected] Name: Tarek Soliman Partner: WU E-mail: [email protected] Disclaimer: This publication has been funded under the small collaborative project PRATIQUE, an EU 7th Framework Programme for Research, Technological Development and Demonstration addressing theme: [kbbe-2007-1-2-03: development of more efficient risk analysis techniques for pests and pathogens of phytosanitary concern call: fp7- kbbe-2007-1]. PRATIQUE No. 212459 Deliverable number: D2.3 Date: 09/05/2017 _____________________________________________________________________ Table of Contents: 1 Introduction and objectives 2.1 Objectives. 2.2 Indicators 2.3 Scoring systems 2.4 Adjustments of the EPPO PRA scheme 3 Changes to the introduction of the assessment of potential economic consequences 4 Questions, indicators and scoring systems for economic impacts 4.1 Introduction 4.2 Adjustments of the scheme 5 Indicators and scoring systems for social impacts 6 Indicators and scoring systems for environmental impacts 6.1 Introduction 6.2 Questions for plant pests 6.3 Questions for pest plants 7 Scoring systems for additional effects and conclusion 3 5 5 6 7 8 10 10 10 21 24 24 24 37 50 1 Introduction and objectives Text in the DoW: Task 2.3 Guidance for identifying indicators and scoring levels of impact in the EPPO PRA scheme To assess economic, environmental and social impacts, key indicators, such as short-term costs for producers and traders, long-term loss of competitiveness, indirect effects in related sectors, pollution of the environment, vulnerability of receptors and loss of biodiversity can be identified. We will determine the key indicators required for impact assessment and develop a quantitative scoring system for these indicators that can be related to the five levels of impact required for each question in the EPPO PRA scheme. Where the level of impact is difficult to quantify, qualitative values will be applied. The scores will be based on real world examples of pest impacts and information acquired by the review undertaken in task 2.1 and tested with case studies. The results will be supplied to WP3 (Subtask 3.1.2) where guidance on the not scoring To undertake impact assessments in PRAs, the assessor onlyof needs tools different levels of risk within the EPPO PRA scheme is being coordinated to assess the impacts quantitatively, but also guidance on the selection of and prospects for the mapping areas with greatest impacts will be explored indicators to score impacts qualitatively so they can be rated according to with WP3 (Subtask 3.3.4). Thisfive) tasklevels will beofundertaken by CSL, LEI, the five (occasionally more than impact proposed in CABI, the EPPO WU,scheme: JKI and minimal, Imperial.minor, moderate, major or massive. This is of great PRA importance for two reasons: 1. Consistency: it enables the risk assessor to apply the PRA scheme correctly and consistently. 2. Transparency: it enhances the communication and common understanding of pest risks. This is of great importance for regulators when deciding whether phytosanitary measures should be taken, determining the strength of such measures and responding to any challenges. The objective of this report is to recommend indicators to associate with the scores for each question in the impact section of the EPPO PRA scheme, and to develop scoring systems. However, during the execution of this task, it became apparent that the questions in the impact section including the notes needed to be revised. Furthermore, the development of methods for qualitative economic impact assessment and environmental impact assessment (task 2.4) coincided with the revision of the impact section of the PRA scheme. Therefore, these methods are also described in this report. The report is structured as follows. In chapter 2 basic principles are explained. In chapters 3, 4 and 5 each EPPO PRA scheme question on economic, environmental and social impacts respectively is presented and indicators are recommended for each impact score. Chapter 6 contains scoring systems for additional effects. In chapter 7, the results are discussed and the recommendations are summarized. 3 Note The EPPO PRA scheme is currently revised. Suggestions for adjustments arise during development of different tasks in PRATIQUE. Task 2.3 has a major role in linking deliverables developed in WP2 to the scheme. Therefore, this report is developed in cooperation with the EPPO PRA panel in order to secure that the final deliverable fits to the revised scheme. 4 2 Basic principles 2.1 Objectives. The suggested indicators and scoring systems need criteria which can be used to evaluate whether they contribute to the objectives as formulated in chapter 1 (consistency and transparency). Furthermore the results of a PRA must lead to clearly interpretable results, which can be used by policy makers to decide whether phytosanitary measures should be applied. At the end of the Pest Risk Assessment stage, the overall risk, composed from likelihood and magnitude, each scored at a 5-point scale to show whether the risk is very low, low, medium, high or very high must be obtained. Ideally, these categories should have little overlap. The objective of this chapter is to propose the criteria for indicators and scoring systems and to explore the consequences for the EPPO PRA scheme. 2.2 Indicators The EPPO PRA scheme provides a decision support scheme for the International Standard for Phytosanitary Measures (ISPM) 11 developed by the International Plant Protection Convention. To assess impacts qualitatively, this deliverable provides indicators to enable assessors to judge consistently which of the five scores should be selected when answering questions in the EPPO PRA scheme. However, since many of the questions cover several types of impact, we have developed indicators for the different types of impact, which we call ‘input indicators’. Input indicator values are input in an assessment module, which calculates the impact, expressed by an ‘output indicator’. The output indicator value summarizes the total economic, social or environmental impact. The challenge is illustrated by looking at question 2.1 in the EPPO PRA scheme (EPPO, 2009) available at the start of PRATIQUE: How great a negative effect does the pest have on crop yield and/or quality to cultivated plants or on control costs within its current area of distribution? Note: Factors to consider are types, amount and frequency of damage and crop losses in yield and quality, together with costs of treatment. In this question, three types of economic impact are distinguished: yield loss, quality loss and increase in production costs. We have investigated how each type of impact can be provided with its own input indicator to ensure that it is considered in sufficient detail. We have also explored how these separate indicators can be combined in an output indicator (e.g. €) to give an overall 5 level risk rating, from minimal to massive, for each question. Since ISPM 11 recommends the use of monetary terms, but allows qualitative indicators, monetary terms have been used to express the impacts wherever possible. To enhance decision making, it is recommended to use as few indicators as possible to summarize all potential indicators. This point is 5 extensively discussed in the review of impact assessment modules (D2.1). According to the recommendations of the review, monetary values will not be used to express environmental and social impacts. 2.3 Scoring systems One of the main objectives of the PRATIQUE-project in general and of this task in particular is to enhance consistency in PRA production. This leads to the following principles: 1. Scale dependency. Scoring systems can be formulated in absolute terms and relative terms. If absolute indicators are applied, the magnitude of the impact is expressed independent from the size of the PRA area and the size of the affected industry. If relative indicators are applied, impacts are assessed in relation to the maximal possible impact, without using absolute terms. Impacts need to be expressed in relative terms in the EPPO scheme so that the impact scale depends of the size of the region and/ or the industry. However the maximum possible impact depends on the size of the PRA area and the size of the affected industry. When performing a quantitative impact assessment, the size of the region and the size of the affected industry have to be determined explicitly. Key data about: - The specification of the product - the size of the area suitable for establishment and spread, - the volume of the host plants, both in production systems, in living areas and in natural environments, - the production value and - export volumes have to be supplied in order to enhance interpretation of scores by decision makers. When performing a qualitative analysis, the final conclusion of the impact assessment will have to embedded in estimates of key figures indicating size and importance of the plants and products at risk. 2. Time dependency. Guidance should be given on how the pest risk analyst should take time into account. In the case of assessing magnitudes, it must be clear if the impacts are expressed in total for the whole period until the time horizon or are expressed per year. It is recommended to express the impacts per year when the impacts have reached the maximum level. When a qualitative impact assessment is conducted, there is no need to take the time constraint into account. In the case of a quantitative approach, it is recommended to present the economic impacts per year and to conduct the economic impact assessment when the maximum geographical distribution has been reached and at 5 years forward in accordance with the assessment of spread. Another option is to evaluate the impact for different scenarios where different proportions 6 of the area of potential establishment are considered to be invaded (e.g. 10 %, 25%). 3. Order of magnitude. Impact categories differ from each other in order of magnitude. This principle is based on logarithmic scales in the case boundaries of impact categories are quantified (which is not applied in the EPPO PRA scheme) and can determined by application of a fixed multiplier. 4. Consistency. Scoring systems with similar indicators will be similar. If yield reduction and change in production costs are both measured in euros, than the scoring system will be similar. 2.4 Adjustments of the EPPO PRA scheme Application of the basic principles to derive indicators and scoring systems, and the application of impact assessment modules to calculate the impact requires adjustment of the EPPO PRA scheme. The following reasons for adjustment are used: 1. All questions regarding economic, environmental and social are subsequently grouped together. 2. The questions are formulated in such a way that answers provide the input for the impact assessment modules, whereas the outputs of those modules will need to be related to the 5level scoring system. Furthermore, in line with principle 1, it is recommended that consistent categories are used for scoring risk (likelihood and impacts) and uncertainty together with the written justification. It is therefore recommended that the categories ‘impossible’ and ‘certain’ are deleted in questions 2.10, 2.12, 2.14 and 2.15. 7 3 Changes to the introduction of the assessment of potential economic consequences In the PRA scheme, the section on impact assessment is preceded by an introduction. This introduction needs to be adjusted for the following reasons: 1. Some basic principles have to be added. 2. This section needs some guidance when the use of the quantitative module is recommended and when the qualitative method will suffice. 3. The numbering of the questions has to be adjusted. Below, an adjusted introduction is presented. The main purpose of this section is to determine whether the introduction of the pest will have unacceptable economic consequences. It may be possible to do this very simply, if sufficient evidence is already available or the risk presented by the pest is widely agreed. Start by answering Questions 6.01 – 6.11. If the responses to question 6.04 and 6.05 are "major" or "massive" or any of the responses to questions 6.06, 6.09, and 6.11 is “major" or "massive” the evaluation of the other questions in this section may not be necessary and you can go to 6.15 unless a detailed study is required or the answers given to these questions have a high level of uncertainty. In cases where the organism has already entered and is established in part of the PRA area, responses to questions 6.01, 6.08 and 6.10, which refer to impacts in its area of current distribution, should be based on an assessment of current impacts in the PRA area in addition to impacts elsewhere. For the qualitative assessment of economic, environmental and social impacts, detailed guidance is provided for every question to help the risk assessor to rate the level of risk. A quantitative module is also available for economic impact assessment1. The quantitative module is appropriate for use in cases when (a) at least moderate economic impacts are expected, (b) these impacts cover a large area or affect different industries and 1 The quantitative economic impact module has not been fully evaluated by the EPPO PRA Development Panel so this module is only directly linked to the PRATIQUE version of Capra (for further explanation see PRATIQUE deliverable 6.5). 8 (c) sources (data, time and skills) are available to conduct a quantitative analysis. Quantitative assessments are particularly likely to be required where the level of impacts is unclear or the analysis is required to justify measures. The key data necessary for a quantitative analysis include: the specification of the product, the size of the area suitable for establishment and spread, the amount of the host plants, both in production systems (total yield), in living areas and in natural environments, the production value and export volumes. Expert judgement is used to provide an evaluation of the likely scale of impact. Detailed guidance is provided for every question to help the risk assessor to rate the level of risk. If precise economic evaluations are available for certain pest/host plant combinations, it will be useful to provide details. The replies should take account of both short-term and long-term effects of all aspects of agricultural, environmental and social impact. When a qualitative impact assessment is conducted, there is no need to take the time constraint into account. In the case of a quantitative approach, it is recommended to present the economic impacts per year and to conduct the economic impact assessment when the maximum geographical distribution has been reached (see q. 6.04) and at 5 years forward (see q. 6.05) Another option is to evaluate the impact for different scenarios where different proportions of the area of potential establishment are considered to be invaded (e.g. 10 %, 25%). In any case, providing replies for all hosts (or all habitats) and all situations may be laborious, and it is desirable to focus the assessment as much as possible. The study of a single case may be sufficient, e.g. if the effect on one host exceeds the effect on all other hosts together. It may be appropriate to consider all hosts/habitats together in answering the questions once, if effects on these hosts are comparable. If a selection is made, it should be justified. Only in certain circumstances will it be necessary to answer the questions separately for specific hosts or habitats. This is the case if the majority of the affected producers suffer minor or moderate impacts, but a small group suffers major or massive impacts. Differences can be caused by different host plants; differences between crops and amenity plants or differences between cropping system: conventional and organic production. When the PRA is performed on a pest proposed for deregulation, the current impact noted in the area may be linked to the implementation of phytosanitary measures. The assessor should evaluate the possible impact for a scenario where these measures targeting the pest are withdrawn. 9 4 Questions, indicators and scoring systems for economic impacts 4.1 Introduction In this chapter, suggestions will be made to the questions regarding economic impacts. The questions will be formulated in such a way that the answers are input in the economic impact assessment module. The old questions numbered with 2.x are followed by new questions numbered with 6.x. In the case of a quantitative assessment, figures have to be given, in the case of a qualitative approach, qualitative scores will suffice. Indicators, both qualitative (option 1) and quantitative (option 2) are presented after the question. The qualitative risk ratings can be used in the qualitative economic impact assessment module (see annex 1) and the quantitative risk ratings in the quantitative economic impact assessment module (see PRATIQUE Deliverable D2.5). Rating guidance for qualitative risk ratings is provided directly after the questions. In the case questions are limited adjusted, examples of performed PRA are given. The organisms are Rhabdoscelus obscurus, Raoiella indica, Drosophila suzukii and Hydrocotyle ranunculoides. 4.2 Adjustments of the scheme 2.1 How great a negative effect does the pest have on crop yield and/or quality to cultivated plants or on control costs within its current area of distribution? Note: factors to consider are types, amount and frequency of damage and crop losses in yield and quality, together with costs of treatment. Level uncertainty: of Low minimal, minor, moderate, major, massive Medium High 6.01 How great a negative effect does the pest have on crop yield and/or quality of cultivated plants or on control costs within its current area of distribution? Note: Effect on crop yield and/or quality are usually expressed as a relative decrease (%) per crop per ha or relative increase in total control costs. When following the rating guidance, it is important to take into account the annual variation in crop yield and quality that normally occurs in different crops. For some crops, e.g. those grown in protected conditions, such as tomatoes, cut flowers and pot plants, the annual yield fluctuations are normally very small and a yield loss greater than 10% can be considered as a massive impact. For crops with high yearly fluctuations, e.g. fruit and arable products and a loss of more than 50% would be needed before it can be considered to be a massive impact. Other crops, such as nursery stock, outdoor vegetables and forestry, take an intermediate position. The main causes of the fluctuation are due to the weather and the lower amount of protection provided, the higher the annual variation in yield. Other aspects to be taken into account include 10 biennial bearing (e.g. fruit) which increases yield variation, whether the product is a bulk product (maize) or a high quality product (e.g. roses) and whether the product is harvested annually (e.g. vegetables). The more quality is an important product feature, the lower the yield variation is. If product the production cycle takes more than one year (e.g. forestry), yield variation due to weather conditions are levelled. In annex 2, a decision tree is presented to determine the yield variation for the product. minimal, minor, moderate, major, massive Level of Low Medium uncertainty: High Rating guidance: Minimal: no yield and/or quality losses recorded. Minor: yield and/or quality losses recorded but pest is fully controlled by nontargeted measures and control costs cannot be distinguished from normal plant protection costs. Moderate: yield and/or quality losses are limited, some targeted measures needed, but additional control costs are limited. Major: yield and/or quality losses are considerable, targeted measures are frequently needed and the treatment is costly. Massive: yield and/or quality losses are severe; high mortality of plants may also occur which can only be reduced by very expensive measures. Examples (the final judgement is based on the worst case): Rhabdoscelus obscurus: Minor to moderate. Palm trees: Minor to Moderate Halfpapp & Storey (1991) performed a survey of 22 palm-nurseries in Queensland (Australia) and interviewed the growers of these nurseries. Seventeen out of the 22 growers had problems with R. obscurus ranging from mild to severe. The 5 nurseries without the problems with the palm weevil were either recently established or had heavy chemical control programs which suggested that frequent application of insecticides may sufficiently control the weevil. According to NIAA (1998): R. obscurus is a serious problem to palm growers in Queensland and causes a loss of public confidence in palms in public and private landscaping. Presently, the palm nursery industry in Queensland and New South Wales report minor occurrence of this pest on a cyclical basis. Palm growers use organophosphate insecticides when R. obscurus is encountered and consider it to be a minor pest (pers. comm. M. Ashton, Biosecurity Queensland, Australia). Banana: Minor Mungomery (1937 cited in Halfpapp & Storey, 1991) did not know of any bananas being attacked in Queensland. Fay (2001) reported that palm nurseries in north Queensland have had to face increasing problems with R. obscurus since 1991. Bianchi & Owen (1965) performed a survey on several islands in the Great Pacific Ocean: no records could be found on damage levels in banana in the literature. 11 Raoiella indica: Minimal to major Coconut: Major Information on damage and related yield losses varies. Information from coconut growers in Trinidad indicate that production was reduced by 75% percent, two years after introduction of the mite (Duncan et al., 2006) although a causal relationship has not been demonstrated. There are reports of severe foliage damage on coconut plantations, young palms and seedlings in India, but no indication of its effect on yield (Sathiamma 1996; Jeppson et al., 1975). Raoiella indica may cause yield loss in nuts of Areca catechu L. (Betel nut palm) when infestations are lingering and severe (Puttarudriah & Channa Basavanna, 1958). (Uncertainty is medium because of the lack of data on yield losses from countries where it is present e.g. India) Date palms: minimal In date palms it is not considered as an economically important pest in the Near-East (Elwan, 2000; Zaid & Arias-Jimenez 2002, Gerson et al. 1983). The EWG considered that the lack of published information on damage on date palms and ornamental palms from Israel, Egypt, Oman and Iran is an indication of the minor importance of the pest in these areas. Bananas: minimal There is severe yellowing on bananas, but no quantitative data on crop yield reduction with damage recorded on leaves in Puerto Rico, Trinidad and Tobago and Venezuela. Damage on leaves due to other pests may be confused with R. indica (Kane et al., 2006; Welbourn, 2007). There are no reports of damage on banana in Israel. Ornamentals: minimal There is no evidence of loss of quality in ornamentals (gingers, Heliconia and Strelitzias) used for planting or as cut flowers. Drosophila suzukii: massive; In California, Oregon and Washington crop losses of up to 100% in some fields have been reported. In Willamette Valley (Oregon) peach growers experienced losses of up to 80 percent in some orchards (Herring, 2009). In the part of the PRA area where the pest has been detected the situation is as follows: In 2010 losses of up to 80% occurred in strawberry crops of the Alpes Maritimes region of southern France (pers. comm. Reynaud, 2010). Similar losses have also been quoted in the Province of Trento in raspberries (pers. comm. Grassi, 2010). Hydrocotyle ranunculoides: Major In the Netherlands, some water boards faced a doubling of costs each year during the 1990s, and, in 2000, the total annual control costs were around 1 million euros (van der Krabben & Rotteveel, 2003). In 2007, in the Netherlands, 11 water boards out of 26 responded to an inquiry stating that they spent an additional 1.8 million euros for the management of H. ranunculoides over and above normal operating costs for this plant (van Valkenburg, pers. comm., 2009). 12 In Flanders, the estimated cost for the management of H. ranunculoides is 1.5 million euros per year (needed during 3 years from 2009) (Triest, pers. comm., 2009). In the UK, the estimate for control of the total area infested by H. ranunculoides by herbicides was between £250,000 and £300,000 per year (Harper, 2002). In 2008, £1.93 million were spent on the management and disposal of H. ranunculoides (Newman, pers. comm., 2009). In 6 years, the costs were multiplied 7 times. Xanthomonas axonopodis pv. allii: Major In countries where it is present Xanthomonas axonopodis pv. allii has caused significant yield losses of onions and high control costs when conditions have been suitable. Xanthomonas pv. allii negatively affects bulb size of onions because it destroys the foliage thus reducing yield. In the continental United States, yield losses in onions crops ranging from 10 to 50% were reported (Nunez et al., 2002; Schwartz & Otto, 2000). In Réunion Island, yield losses of up to 50% were also recorded (Pruvost, unpublished data). Data from Barbados indicates cases where an entire onion crop loss was observed (O’ Garro & Paulraj, 1997). 2.2 How great a negative effect is the pest likely to have on crop yield and/or quality in the PRA area without any control measures? Note: the ecological conditions in the PRA area may be adequate for pest survival but may not be suitable for pest populations to build up to levels at which significant damage is caused to the host plant(s). Rates of pest growth, reproduction, longevity and mortality may all need to be taken into account to determine whether these levels are exceeded. Consider also effects on non-commercial crops, e.g. private gardens, amenity plantings. Level uncertainty: of Low minimal, minor, moderate, major, massive Medium High 2.11 How likely is it that natural enemies, already present in the PRA area, will not reduce populations of the pest below the economic threshold? Note: For pest plants, natural enemies include herbivores and pathogens. Level uncertainty: very unlikely, unlikely, moderately likely, likely, very likely of Low Medium High New question 6.02 How great a negative effect is the pest likely to have on crop yield and/or quality of cultivated plants in the PRA area without any control measures? 13 Note: This information can be derived from trials where no measures are taken on some plots. Consider the note and the answer to question 6.01. The ecological conditions in the PRA area may be adequate for pest survival but may not be suitable for pest populations to build up to levels at which significant damage is caused to the host plant(s). Rates of pest growth, reproduction, longevity and mortality may all need to be taken into account to determine whether these levels are exceeded despite the presence of natural enemies. Consider also the effects on non-commercial crops, e.g. private gardens, amenity plantings. Level uncertainty: of Low minimal, minor, moderate, major, massive Medium High Minimal: no yield and/or quality losses are expected Minor: yield and/or quality losses are expected but they cannot be distinguished from normal variation Moderate: yield and/or quality losses are limited but they exceed normal variation, some targeted measures may be necessary Major: yield and/or quality losses can be considerable, targeted measures may frequently be needed Massive: yield and/or quality losses will be severe; and/or high mortality of plants is expected Examples: R. obscurus: Minor The effect is expected to be limited since it seems unlikely that large populations will build up in glasshouses and most damage will be caused by the import of infested plants from areas where the pest is present and not from new infestations in the PRA area. Raoiella indica: Minor The main host where damage is recorded (coconut) is present in very low quantities in the EPPO region (beach landscape in Canary Islands). There is banana production in the EPPO region, but the crop yield reduction due to R. indica on banana is unknown. No judgement can be made for ornamental plants as there is no information. Phoenix canariensis is recorded as a host but there is no specific evidence of yield loss. Drosophila suzukii: massive Based on the information available regarding significant damage already occurring within the PRA area, the the likelihood of 'massive' negative effects on crop yield is considered to be high. However, recent experiences in North America since 2008 have shown that, 14 although there are annual variations in pest populations, the impact of this species on local agriculture tends to decrease due to increased awareness, improved monitoring, and more effective targeting of treatments (pers comm. Hueppelsheuser and Hauser, 2010). Hydrocotyle ranunculoides: Minimal There are currently no impacts recorded in crops, but it was considered that flooding of low lying agricultural areas is possible due to blockage of water level control structures. New question: 6.03 How great a negative effect is the pest likely to have on yield and/or quality of cultivated plants in the PRA area without any additional control measures? Note: Consider the note and answer to question 6.01 and consider the pest survival and population growth when producers only apply current crop protection measures. Level uncertainty: of Low minimal, minor, moderate, major, massive Medium High Rating guidance: Minimal: no yield and/or quality losses are expected. Minor: yield and/or quality losses are expected but they cannot be distinguished from normal variation and are insufficient to justify additional measures. Moderate: yield and/or quality losses are limited, some targeted measures may be necessary. Major: yield and/or quality losses can be considerable, targeted measures may be frequently be needed. Massive: yield and/or quality losses will be severe; high mortality of plants is expected. 2.3 How easily can the pest be controlled in the PRA area without phytosanitary measures? Note: Consider the existing control measures and their efficacy against the pest. Difficulty of control can result from such factors as lack of effective plant protection products against this pest, resistance to plant protection products, difficulty to change cultural practices, occurrence of the pest in natural habitats, private gardens or amenity land, simultaneous presence of more than one stage in the life cycle, absence of resistant cultivars. very easily, easily, with some difficulty, with much difficulty, impossible Level of Low Medium High uncertainty: 15 6.04 How great a negative effect is the pest likely to have on yield and/or quality of cultivated plants in the PRA area when all potential measures legally available to the producer are applied, without phytosanitary measures? Note: Consider the note and answer to question 6.01. Take into account the existing and potential control measures and their efficacy against the pest. Difficulty of control can result from such factors as lack of effective plant protection products against this pest, resistance to plant protection products, difficulty to change cultural practices, occurrence of the pest in natural habitats, private gardens or amenity land, simultaneous presence of more than one stage in the life cycle, absence of resistant cultivars. Include both normal farm practice costs and costs of control of measures which are additional to the common agricultural practice and which are assumed to be taken from a sound managerial perspective, in particular: - ease of detection of the pest: species that are difficult to detect will require a greater surveillance and monitoring effort which will indirectly result in higher production costs. - treatment: treatment options may vary (plant protection products, physical removal, etc.) Treatment costs may be divided into operating (e.g. chemical, fuel, equipment) and labour (i. e. hours per ha). minimal, minor, moderate, major, massive Level of Low Medium High uncertainty: Rating guidance: Minimal: no yield and/or quality losses expected. Minor: yield and/or quality losses are expected or cannot be distinguished from normal variation. Moderate: yield and/or quality losses are limited Major: yield and/or quality losses can be considerable. Massive: yield and/or quality losses will be severe; high mortality of plants is expected. 2.4 How great an increase in production costs (including control costs) is likely to be caused by the pest in the PRA area? Note: both normal farm practice costs and costs of control should be included, in particular: - ease of detection of the pest: species that are difficult to detect will require a greater surveillance and monitoring effort which will indirectly result in higher production costs. - treatment: treatment options may vary (plant protection products, physical removal,…). Treatment costs may be divided into operating (e.g. chemical, fuel, equipment) and labour (i. e. hours per ha). minimal, minor, moderate, major, massive 16 Level uncertainty: of Low Medium High 6.05 How great an increase in production costs (including control costs) is likely to be caused by the pest in the PRA area in the absence of phytosanitary measures? Note: This is evaluated on the basis of the relative increase (%) in total costs (e.g. €). Include the costs of all additional measures which are considered in question 5.04 and costs incurred to prevent environmental impacts. Consider also the answer to question 6.02. Level uncertainty: of Low minimal, minor, moderate, major, massive Medium High Rating guidance: Minimal: no increase of costs expected. Minor: additional costs are negligible. Moderate: some targeted measures needed, with limited additional costs. Major: targeted measures frequently needed, which are expensive. Massive: targeted measures intensively used which are very expensive. Examples Rhabdoscelus obscurus: Minor The pest is difficult to control. Production costs will increase due to extra applications of crop protection products and due to plant losses (symptomatic plants can not be sold and will have to be destroyed). Costs for crop protection in glasshouse horticulture are, however, relatively low. For pot plants in general the costs for crop protection agents are about 0.4% of the total production costs (Lauwere & Bremmer, 2006). Costs for crop protection (including labour and fertilizers) are about 1 and 2 % of the total production costs for Chamaedorea and Chrysalidocarpus lutescens (Van Woerden, 2005). Thus the increase in production costs will be mainly determined by the loss of plants due to the pest. These losses are, however expected to be mainly limited to plants that had already been infested prior to import. Raoiella indica: Minimal The main host where damage is recorded (coconut) is present in very low quantities in the EPPO region (beach landscape in Canary Islands). There is banana production in the EPPO region, but the crop yield reduction due to R. indica on banana is unknown. No judgement can be made for ornamental plants as there is no information. Phoenix canariensis is recorded as a host but there is no specific evidence of yield loss. Drosophila suzukii: Moderate Costs will be incurred for labour and materials associated with monitoring, sanitation management, and additional targeted applications of plant protection products. Due to limited experience in areas experiencing D. 17 suzukii infestations, there is some uncertainty regarding exactly how expensive control and management strategies may be. Optimal control management strategies are yet to be well defined and these may or may not incur increased costs in terms of chemical use and/or labour. Hydrocotyle ranunculoides: Moderate to major Control costs could be similar to those already spent in infested parts of the PRA area. A weevil, Listronotus elongatus, has been demonstrated to feed exclusively on Hydrocotyle species in Argentina, and further work on this potential bio-control agent is planned in the UK (Newman, 2003). The cost of a preliminary study was £30.000, but the cost of a full biological control project would be £500.000 (Newman, pers. comm., 2009). 2.10 How likely is the presence of the pest in the PRA area to cause losses in export markets? Note: consider the extent of any phytosanitary measures likely to be imposed by trading partners. Impossible/very unlikely, unlikely, moderately likely, likely, very likely/certain Level of Low Medium High uncertainty: 6.06 Based on the total market, i.e. the size of the domestic market plus any export market, for the plants and plant product(s) at risk, what will be the likely impact of a loss in export markets, e.g. as a result of trading partners imposing export bans from the PRA area? Note: consider whether plant products potentially affected by the pest are exported from the PRA area and how important such exports are, for example by estimating the proportion of production that is exported. Take into account the major existing (or potential) export markets and how likely each is to impose an export ban from the PRA area. This is expressed as a relative decrease in market size. Level uncertainty: of Low minimal, minor, moderate, major, massive Medium High Rating guidance Minimal: no effect on market size is expected. Minor: the effect on market size is negligible and cannot be distinguished from normal variation. Moderate: some effects on market size are expected. Major: considerable effects on market size are expected. Massive: severe effects on market size are expected. Examples Phytophthora ramorum causes damage to a range of host plants in nursery stock. It is likely that infestation in Europe will cause export bans in the USA 18 and Canada. However, these export markets are of limited importance. Therefore, the score is ‘minor’. Meloidogyne chitwoodi leads to minor or moderate yield loss in potato production. Although M. chitwoodi has the quarantine status in some export countries, the presence of M. chitwoodi in some parts of the EU has not reduced the exported volume to these countries. Therefore, the score is ‘minor’. Anoplophora glabripennis larvae feed beneath the bark and then bore into the wood. This may kill forest and amenity trees and reduce the quality of timber because of bore-holes. The most important threat is the reduction of export of trees and wood because of the quarantine status of this organism in most parts of the world. Because of the relative importance of export the score is ‘major’. 2.5 How great a reduction in consumer demand is the pest likely to cause in the PRA area? Minimal extent, minor extent, moderate extent, major extent, massive extent Level of Low Medium High uncertainty: 6.07 To what extent will direct impacts be borne by producers? Note: This is evaluated as the proportion (%) of total economic impact (the sum of the questions 6.04, 6.05 and 6.06) borne by the producers. Producers can try to transfer economic losses to consumers and to other producers in order to decrease impacts on themselves. Factors that enable producers to decrease impacts include: - the alternative use of the product, e.g. a shift from human consumption to use for animal feed - the negotiation power of the producer to change the price of the product, - the potential to grow other crops. The ease with which production can be adjusted depends on: - the time needed for new crops to reach full production, e.g. one season for potatoes and several years for apples, - the availability of factors such as labour, land and the investments which may have to be made to increase production (investment in plants for planting, buildings such as glasshouses, etc.), - factors such as market expectations and the potential for storage of the product until prices rise. Factors that limit producers capacity to decrease impacts include: - consumer responsiveness (can consumers postpone consumption or shift to substitutes?), - reductions in market share due to loss of image or dependency on the harmed products, such as wood which is used as packaging 19 material. This can also affect the sale of products which are not infested. A producer will almost never be able to pass on all costs. More details including a decision tree to derive indirect impacts are presented in Annex 3. Level uncertainty: Option 1: minimal, minor, moderate, major, massive of Low Medium High Option 2: no judgment possible/ ask an economist When no judgment is chosen, the assessor should specify in the PRA that the impact may be overestimated. Rating guidance (see annex 2) Minimal: almost totally decrease of direct impacts because prices increase due to lack of any possibilities for consumers to use alternatives or to postpone consumption Minor: direct impacts decrease largely because prices increase due to limited possibilities for consumers to use alternatives or to postpone consumption Moderate: direct impacts decrease partly because prices increase somewhat due to some possibilities for consumers to use alternatives or to postpone consumption or the producers has some possibilities to shift to alternative products. Major: direct impacts decrease slightly because prices almost don’t increase due to possibilities for consumers to use alternatives or to postpone consumption and the producers has limited possibilities to shift to alternative products. Massive: decreasing direct impacts cannot be expected because prices don’t increase due to possibilities for consumers to use alternatives or to postpone consumption and the producers has no possibilities to shift to alternative products. 20 5 Indicators and scoring systems for social impacts In this chapter adjustments to the questions regarding social impacts are presented. The old questions numbered with 2.x are followed by new questions numbered with 6.x. Rating guidance for qualitative scores is provided. 2.8 How important is social damage caused by the pest within its current area of distribution? Note: Social effects may arise as a result of impacts to commercial or recreational values, life support/human health, biodiversity, aesthetics or beneficial uses. Social effects could be, for example, changing the habits of a proportion of the population (e.g. limiting the supply of a socially important food) damaging the livelihood of a proportion of the human population, affecting human use (e.g. water quality, recreational uses, tourism, animal grazing, hunting, fishing). Effects on human or animal health, the water table and tourism could also be considered, as appropriate, by other agencies/authorities. Level uncertainty: of Low minimal, minor, moderate, major, massive Medium High 6.10 How important is social damage caused by the pest within its current area of distribution? Note: Social effects are impacts on human well-being, other than economic impacts. The main social effects are: • Landscape effects. To assess the impacts on the landscape two elements need to be involved: o Land use function (agriculture, living area) o Contribution to wellbeing (aesthetic value, cultural/ historic value) • Loss of employment • Effects on human health (in addition to effects on plant health) • Products and services such as water quality, animal grazing, hunting and fishing (in addition to effects on plant health). Effects on human or animal health, the water table and tourism could be considered, as appropriate, by other agencies/authorities. Level uncertainty: of Low minimal, minor, moderate, major, massive Medium High Rating guidance landscape effects Minimal: damage to landscape has no consequences for landscape value Minor: some plants which play an important role in determining the attractiveness of the landscape are damaged or die 21 Moderate: some plants that play an important role in determining the attractiveness of the landscape are damaged or die Major: a substantial proportion of the plants that play an important role in determining the attractiveness of the landscape are damaged or die Massive: the majority of the plants that play an important role in determining the attractiveness of the landscape die. Rating guidance for loss of employment Minimal: No loss of employment occurs due to economic impact occurs Minor: Some loss of employment due to economic impacts may occur, but cannot be distinguished from normal loss of employment Moderate: Loss of employment due to economic impacts occurs to a limited extent Major: Considerable loss of employment and bankruptcy due to economic impacts occurs Massive: Due to economic impacts, the majority of the affected producers go bankrupt and their employees loose there job Combined rating guidance: Take the maximum score of landscape effects and loss of employment NB! No rating guidance for human health effects and products and services will be provided in order to ensure that the risk rating for this question will not be dominated by these aspects. Effects on human health and products and services should be reported as additional comments. Example Phytophthora ramorum causes damage to different host plants in managed gardens. Since some of these plants play an important role in determining the attractiveness of the landscape (and may thus influence the number of tourists), the score is at least moderate. In areas where most of these plants are hosts, the score can be major or massive. 2.9 How important is the social damage likely to be in the PRA area? Level uncertainty: of Low minimal, minor, moderate, major, massive Medium High 6.11 How important is social damage likely to be in the PRA area? Level uncertainty: of Low minimal, minor, moderate, major, massive Medium High Rating guidance landscape effects Minimal: damage to landscape has no consequences for landscape value Minor: some plants which do not play an important role in determining the attractiveness of the landscape are damaged or die 22 Moderate: some plants that play an important role in determining the attractiveness of the landscape are damaged or die Major: a substantial proportion of the plants play an important role in determining the attractiveness of the landscape are damaged or die Massive: the majority of the plants that play an important role in determining the attractiveness of the landscape die. Rating guidance loss of employment Minimal: No loss of employment occurs due to economic impacts Minor: Some loss of employment due to economic impacts may occur, but cannot be distinguished from normal loss of employment Moderate: Loss of employment due to economic impacts occurs to a limited extent Major: Considerable loss of employment and bankruptcy due to economic impacts occurs Massive: Due to economic impacts, the majority of the affected producers go bankrupt and their employees loose there job Combined rating guidance: Take the maximum score of landscape effects and loss of employment NB! No rating guidance for human health effects and products and services should be provided in order to ensure that the risk rating for this question will not be dominated by these aspects. Effects on human health and products and services should be reported as additional comments. 23 6 Indicators and scoring systems for environmental impacts 6.1 Introduction In this chapter, the two questions (2.6 and 2.7) about the environmental impacts are converted into a set of questions, covering all different aspect of environmental impacts. Rating guidance has been provided as well as examples. Finally, a rating system has been presented to summarize the scores of the sub-questions into a final score for environmental impacts. Furthermore, two separate sets of questions have been provided for plant pests and for pest plants. 6.2 Questions for plant pests 6.08. How important is the environmental impact caused by the pest within its current area of invasion? (former question 2.6) N/A, Minimal, minor, moderate, major, massive In this question we rate the current environmental impact in other invaded regions that can be used as indicator for determining the potential environmental impact in the PRA area (Q. 6.09). If the species has not invaded any other area, or if the invasion is too recent and too little is known about its ecology in the invaded areas, this question cannot be answered properly (assuming that no additional investigations can be undertaken during the time available for producing the PRA). The assessor may choose to go directly to Q 6.09. He/she may also choose to answer these questions based on well studied closely-related species or data for the target species from the region of origin. Although the concept of “environmental impact” of an indigenous species on native biodiversity and ecosystem is debatable, in some cases native species clearly have an environmental impact, usually resulting either from climate change or ecological mismanagement (e.g. Dendroctonus ponderosae presently causing serious outbreaks and extending its range in Canada, various weeds now invasive in their native range, etc.). Nevertheless, the assessor should take into account the fact that the environmental impact of a pest in its region of origin is often a very poor predictor of potential impact in regions where it has been introduced. In particular, the absence of any obvious environmental impact in a region of origin should not be considered as a predictor for a low impact in a new area. Examples of species for which Q. 6.08 may be difficult to answer include: - Choristoneura fumiferana and Pissodes strobi: These North American species have never invaded any area. - Anoplophora glabripennis and A. chinensis: For the moment (2010) all outbreaks in invaded areas worldwide are still under eradication and the 24 - - beetle has not yet been studied in natural areas or even semi-natural forests in invaded areas. Diaphania perspectalis and Paysandisia archon: Their invasion in Europe is too recent to accurately assess their current impacts, and they have never invaded any other region. Most pathogens and strictly agricultural pests have been poorly studied for their environmental impact. When data on impact are available in several invaded regions, priority should be given to impact observed in regions that are most closely related, geographically and eco-climatologically, to the PRA region. However, data from other regions should not be excluded. For example, when performing a PRA on an invasive pest for the entire Europe, data on impact already observed in Europe should be given priority, but information from other regions should also be provided. In any case, the assessor should specify the region where the information on impact has been gathered. 6.08.0A Based on the above, do you consider that the question on the environmental impact caused by the pest within its current area of invasion can be answered? If Yes: Go to 6.08.01 If No, but information is available for the native area of the pest, Go to 6.08.01. If No, but there is some evidence that the environmental impact may be significant in the PRA area: answer N/A for 6.08 and Go to 6.09.0C If No, and the assessor is certain that, in any case, the environmental impact will be lower than the economic impact (e.g. a purely agricultural pest not known to occur in other environments): answer N/A for 6.08 and 6.09 (the assessor will have to justify this decision). The pest has to be assessed for three categories of impact using several indicators that need to be rated. The precise region (and whether invaded or native) and the species (target species or closely-related species) for which the question is answered should be clearly described by the assessors. The subquestions to be answered are organized as follows: Negative impact on native biodiversity 6.08.01. To what extent does the pest cause a decline in native species? 6.08.02. To what extent does the pest cause changes in the composition and structure of native species communities? 6.08.03. To what extent does the pest hybridize with native species? Alteration of ecosystem processes and patterns 6.08.04. To what extent does the pest cause physical modifications of habitats? 6.08.05. To what extent does the pest cause changes in nutrient cycling and availability? 6.08.06. To what extent does the pest cause modifications of natural successions? 6.08.07. To what extent does the pest disrupt trophic and mutualistic interactions? 25 Conservation impacts 6.08.08. To what extent does the pest occur in habitats of high conservation value? 6.08.09. To what extent does the pest cause harm to rare or vulnerable species? For each of the indicators, a rating is given based on three choices: Low, Medium or High. Information is provided for each indicator on the meaning of these scores. For each answer, the associated uncertainty should also be assessed, the possible options are Low, Medium or High. Low: the assessor has low uncertainty that the rating is correct (i.e. the impact has been studied and measured, or the observed damage, the bio-ecological characteristics of the species, or the environmental conditions allow the assessor to be highly confident of the accuracy of the rating). Medium: The assessor has moderate uncertainty that the rating is correct (i.e. the impact has been studied but some contradictory results have been identified, or the observed damage, the bio-ecological characteristics of the species, or the environmental conditions allow the assessor to be moderately confident of the accuracy of the rating). High: The assessor has high uncertainty that the rating is correct (i.e. the impact has been studied but the results are contradictory, or the observed damage, the bio-ecological characteristics of the species, or the environmental conditions do not allow the assessor to be moderately confident of the accuracy of the rating). Negative impact on native biodiversity Note 1: The word “native” in “native species” or “native biodiversity” throughout Questions 6.08 and 6.09 should be understood in a broad sense, i.e. it should also include species that have been naturalised for centuries and that play an important role in the ecosystems or local cultural heritage, such as walnut (Juglans) or chestnut (Castanea) in Europe. The assessor may also include other, more recently introduced beneficial organisms such as biological control agents or exotic plants that play a role in ecosystem services, e.g. plants used against erosion. Note 2: If possible, all mechanisms of impact on native biodiversity should be considered, but only the mechanism providing the highest score and lowest uncertainty is kept for the scoring of the indicators. Mechanisms of impact may include, among others: Herbivory: Most impacts by plant pests occur through direct feeding on native plants. E.g., the emerald ash borer Agrilus planipennis feeds on, and kills native Fraxinus spp. in North America. The hemlock woolly adelgid, Adelges tsugae, severely affects natural stands of Tsuga spp. in Eastern North America. 26 Plant pathology: A pathogen directly impacts its host plant by causing disease, e.g. Ophiostoma novo-ulmi decimated Ulmus spp. by causing Dutch elm disease in Europe and North America. Nematodes may also cause plant disease, e.g. Bursaphelenchus xylophilus causes pine wilt, which devastates native pine stands in East Asia. Disease transmission: Alien pests can affect native plants through disease transmission, e.g. Scolytus multistriatus, a European bark beetle, is a vector of the Dutch elm disease in North America. This can also include pests that facilitate the attack of a pathogen, without being vectors themselves. For example, the European beech scale, Cryptococcus fagisuga, increases the susceptibility of the fungus Neonectria faginata, causal agents of the beech bark disease in North America. Hybridization: Hybridization between an alien and a native species or subspecies may affect the genetic identity of native species or sub-species, although well documented examples are rare for plant pests. The Australian lycaenid butterfly Zizina labradus has apparently locally displaced the endemic Z. oxleyi in New Zealand. In insects, examples are most common between alien and native honey-bee and bumble-bee sub-species. Competition for resources: Alien herbivores may affect native biodiversity by competing for food or by affecting the quality and availability of food. For example, the scale insect Icerya purchasi, by killing endangered plants in the Galapagos, has also caused local extinction of host specific Lepidoptera. In North America, the Asian adelgid Pineus boerneri, is displacing P. coloradensis in red pine plantations, by reducing host plant quality and forcing the native species to move to other hosts. Predation: Plant pests may also affect native species through predation on other animals. For example, the ladybird Harmonia axyridis, a pest of vineyards in North America also affects native ladybird populations through predation. Apparent competition: Apparent competition occurs when the presence of one species indirectly decreases the fitness of another through the increased presence of a shared enemy. An example is the variegated leafhopper, Erythroneura variabilis, which, when introduced into California, affected populations of the native E. elegantula by enhancing populations of a shared egg parasitoid. Pesticide use: An intensive use of non-specific pesticides (including biopesticides) over wide areas may affect native biodiversity, in particular when used in natural or semi-natural habitats (e.g. forests, swamps, etc.) . For example, the use of Bt over wide areas in North America to control Lymantria dispar locally affects the Lepidopteran fauna; the chemical control of alien mosquitoes over wide areas worldwide has a negative impact on the aquatic fauna. 27 6.08.01. To what extent does the pest cause a decline in native species? Level uncertainty: of Low Medium Low, Medium, High High Rating guidance Low The decline in native species populations has been studied but not observed. If no study has been carried out to determine the level of impact, according to the information available on observed damage, bio-ecological characteristics of the species and environmental conditions, a decline in native species is unlikely. Examples: The impact of alien gall wasps Andricus spp. on native gall wasps in Britain has been studied but no significant impact was found. Phytophthora infestans mainly attack cultivated crops in Europe and the effect on native species populations is unlikely. Medium A decline in native species populations has been observed but the decline is not persistent and is limited in area. If no study has been carried out to determine the level of impact, according to the information available on observed damage, bio-ecological characteristics of the species and environmental conditions, the impact level is considered to be medium. Examples: Severe outbreaks of Lymantria dispar in North America are known to cause local decline in host trees and associated fauna (e.g. birds), but most studies suggest that the decline is usually temporary. Cryphonectria parasitica has severely affected populations of European chestnut when it arrived in Europe, but chestnut forests have largely recovered. High AO decline in native species populations has been observed, and the impact is likely to be widespread within the habitats occupied by the species and persistent if no management option is taken. If no study has been carried out to determine the level of impact, according to the information available on observed damage, bioecological characteristics of the species and environmental conditions, the impact level is considered to be high. Examples: Adelges piceae has decimated natural Fraser fir populations in Eastern North America. Ophiostoma novo-ulmi has caused the general decline of elm species in Europe and North America. Although studies to accurately measure the impact of Agrilus planipennis on populations of several ash species in North America are still lacking, the fact that the beetle has already killed over 40 million trees and the prediction that the damage is going to continue unabated for the foreseeable future strongly suggests that it has a severe effect on ash populations and the associated fauna. 28 6.08.02. To what extent does the pest cause changes in the composition and structure of native species communities? Level uncertainty: of Low Medium Low, Medium, High High Rating guidance Low Changes in native community composition and structure have been studied but not observed. If no study has been carried out to determine the level of impact, according to the information available on observed damage, bio-ecological characteristics of the species and environmental conditions, a decline in native community composition and structure is unlikely. Examples: All alien pests and pathogens attacking mainly or exclusively crop species will fall into this category. Species (e.g. Lilioceris lilii) that are specific to plants species that do not, or rarely dominate plant communities (e.g. lilies) will also score Low here. Medium Changes in native community composition and structure have been observed but the changes are not persistent and limited in area. If no study has been carried out to determine the level of impact, according to the information available on observed damage, bioecological characteristics of the species and environmental conditions, the impact level is considered to be medium. Examples: Defoliation by Lymantria dispar can cause a major shift in tree species in North America either through tree mortality or via seed failure or mortality of oak seedling. Bird communities may also be modified. However, in general, defoliations by L. dispar only induce temporary changes. High Significant changes in native community composition and structure have been observed and the impact is likely to be widespread within the habitats occupied by the species and persistent if no management option is taken. If no study has been carried out to determine the level of impact, according to the information available on observed damage, bio-ecological characteristics of the species and environmental conditions, the impact level is considered to be high. Examples: Mortality of Fraser fir caused by Adelges piceae in North America has totally altered plant communities in these forest ecosystems. Cryphonectria parasitica has had a same effect on plant communities associated to American walnut forests. The decline of eastern hemlock due to Adelges tsugae in North America strongly affects bird species composition. 29 6.08.03. To what extent does the pest hybridize with native species? Level uncertainty: of Low Medium Low, Medium, High High Rating guidance Low Hybridization with native species has been studied but has not been observed. If no study has been carried out to determine the level of impact, according to the information available, hybridization with native species is very unlikely. Examples: All alien species without taxonomically very closely related species (congeneric sister-species or sub-species) will fall into this category. Medium Hybridization with native species/subspecies has been observed in the field or in the lab, but no fertile offspring have been produced, or if fertile offspring have been produced, the hybrid has a lower fitness than its parents and will not replace the native species/subspecies. If no study on hybridization has been carried out, hybridization is considered possible because of the presence of sister species or subspecies in the invaded area. Examples: Hybridization between alien and native Bombus spp. is obtained in the laboratory, but their offspring is usually sterile. In Japan, fertile hybridization is obtained in the lab between the native parasitoid Torymus beneficus and the alien T. sinensis, but studies showed that hybridization in the field was marginal. High Hybridization with native species/subspecies has been observed in the field or in the laboratory and fertile offspring have been produced. The hybrid has a high fitness and is replacing, or is able to replace the native species or sub-species. If no study on hybridization has been carried out, fertile hybridization is considered likely because of the presence of sister species or subspecies in the invaded area and the occurrence of other, similar cases with taxonomically closely-related species. Example: The Australian lycaenid butterfly Zizina labradus has apparently locally displaced the endemic Z. oxleyi in New Zealand. Introductions in North-Western Europe of two southern European sub-species of Apis mellifera has caused large-scale gene-flow and introgression between these sub-species and the native subspecies, whose native populations are now threatened. Alteration of ecosystem processes and patterns Note : Only the impact on natural or semi-natural habitats should be considered when assessing the impact on ecosystem processes and patterns. 30 However, natural and semi-natural habitats have to be considered in a broad sense, i.e. every habitat that is not under constant human management. It includes all EUNIS habitat types 1 (http://eunis.eea.europa.eu/habitats-codebrowser.jsp), except I (Regularly or recently cultivated agricultural, horticultural and domestic habitats) and J (Constructed, industrial and other artificial habitats). For example, grasslands that are regularly mown are included as well, but not those that are repeatedly re-seeded. 6.08.04. To what extent does the pest cause physical modifications of habitats (e.g. changes to the hydrology, significant increase of water turbidity, light interception, alteration of river banks, changes in fire regime, etc.)? Level uncertainty: of Low Medium Low, Medium, High High Rating guidance Low The physical modification of habitats has been studied but not observed. If no study has been carried out to assess the impact, according to the information available on observed damage, bioecological characteristics of the species and environmental conditions, a physical modification of habitats is unlikely. Examples: All alien pests and pathogens attacking mainly or exclusively crop species will fall into this category, as well as those impacting non-dominant plants, in particular herbaceous plants. Medium A physical modification of habitats has been observed but the impact is not persistent and limited in area. If no study has been carried out to assess the impact, according to the information available on observed damage, bio-ecological characteristics of the species and environmental conditions, the impact level is considered to be medium. Examples: Defoliations and tree mortality by Lymantria dispar in North America increases light penetration to the forest floor and water drainage. These changes are usually considered as temporary. Tree mortality caused by Elatobium abietinum in relatively dry areas such as Arizona increases the amount of dry fuel material in the forest and increases the risk of wildfire. High A physical modification of habitats has been observed and the impact is likely to be widespread within the ecosystem where the species is present and persistent if no management option is undertaken. If no study has been carried out to assess the impact, according to the information available on observed damage, bioecological characteristics of the species and environmental conditions, the impact level is considered to be high. Examples: Hemlock mortality due to Adelges tsugae in North America modifies hydrological processes and the forest floor microclimate. 31 6.08.05. To what extent does the pest cause changes in nutrient cycling and availability (e.g. significant changes in nutrient pools in topsoils or in water)? Level uncertainty: of Low Medium Low, Medium, High High Rating guidance Changes in nutrient cycling have been studied but not observed. If Low no study has been carried out to assess the impact, according to the information available on observed damage, bio-ecological characteristics of the species and environmental conditions, a change in nutrient cycling is unlikely. Examples: All alien pests and pathogens attacking mainly or exclusively crop species will fall into this category, as well as those impacting non-dominant plants, in particular herbaceous plants. Medium Changes in nutrient cycling have been observed but the impact is not persistent and limited in area. If no study has been carried out to assess the impact, according to the information available on observed damage, bio-ecological characteristics of the species and environmental conditions, the impact level is considered to be medium. Examples: Defoliation by Lymantria dispar in oak forests in North America alters carbon allocation and nitrogen cycling, which has consequences such as acidification of stream water. These effects are usually considered as temporary. High Changes in nutrient cycling have been observed and the impact is likely to be widespread where the species is present and persistent if no management option is undertaken. If no study has been carried out to assess the impact, according to the information available on observed damage, bio-ecological characteristics of the species and environmental conditions, the impact level is considered to be high. Examples: In Western North America, spruce defoliation by Elatobium abietinum influences short- and long-term nutrient cycling in forest stands. Nutrient availability may be increased in the shortterm, but over longer periods defoliation may result in a net loss of nutrients from the stand. Hemlock mortality caused by Adelges tsugae results in a dramatic increase in inorganic N availability and the nitrification rate, resulting in nitrate leaching. 32 6.08.06. To what extent does the pest cause modifications of natural successions (e.g. acceleration or temporary freezing of successions)? Level uncertainty: of Low Medium Low, Medium, High High Rating guidance Low The modification of natural successions has been studied but has not been observed. If no study has been carried out to assess the impact, according to the information available on observed damage, bio-ecological characteristics of the species and environmental conditions, a modification of natural successions is unlikely. Examples: All alien pests and pathogens attacking mainly or exclusively crop species will fall into this category, as well as those impacting non-dominant plants, in particular herbaceous plants. Medium A modification of natural successions has been observed but the impact is not persistent and limited in area. If no study has been carried out to assess the impact, according to the information available on observed damage, bio-ecological characteristics of the species and environmental conditions, the impact level is considered to be medium. Examples: Lymantria dispar outbreaks modify natural successions in defoliated oak forests but changes are only temporary. High A modification of natural successions has been observed and the impact is likely to be widespread within that ecosystem in the current distribution of the species and persistent if no management option is taken. If no study has been carried out to assess the impact, according to the information available on observed damage, bio-ecological characteristics of the species and environmental conditions, the impact level is considered to be high. Examples: Cryptococcus fagisuga facilitates beech bark disease in North America, which causes long term changes in natural successions that disadvantages beech. The predation of Anoplolepis gracilipes on the red land crab in the rain forest of Christmas Island has totally modified natural successions in this natural ecosystem. 6.08.07. To what extent does the pest disrupt trophic and mutualistic interactions (e.g. disruption of food web, pollination or plant-mycorrhiza webs leading to ecosystem imbalance)? Level uncertainty: of Low Medium Low, Medium, High High 33 Rating guidance Low The disruption of trophic and mutualistic interactions has been studied but not observed. If no study has been carried out to assess the impact, according to the information available on observed damage, bio-ecological characteristics of the species and environmental conditions, a disruption of trophic and mutualistic interactions is unlikely. Examples: Studies have investigated the impact of Cameraria ohridella on trophic interactions between native leaf miners and parasitoids, but no impact was found. All alien pests and pathogens attacking mainly or exclusively crop species will fall into this category. Medium A disruption of trophic and mutualistic interactions has been observed but the impact is not persistent and limited in area. If no study has been carried out to assess the impact, according to the information available on observed damage, bio-ecological characteristics of the species and environmental conditions, the impact level is considered to be medium. Examples: Lymantria dispar outbreaks enhance parasitoid populations, leading to increased parasitism on rare butterfly and favour mouse populations, leading to an increase in tick populations and Lyme disease incidence. Linepithema humile displaces floral arthropods, including pollinators on various plants in South Africa, but no long term effect on seed sets is observed. The introduction of Apis mellifera and Bombus terrestris worldwide causes local decline of native bees and birds which may locally affect pollination. High A disruption of trophic and mutualistic interactions has been observed and the impact is likely to be widespread within that ecosystem in the current distribution of the species and persistent if no management option is taken. If no study has been carried out to assess the impact, according to the information available on observed damage, bio-ecological characteristics of the species and environmental conditions, the impact level is considered to be high. Examples: The strong decline of important trees such as American chestnut (due to Cryphonectria parasitica), elm species (due to Ophiostoma novo-ulmi), Fraser fir (due to Adelges piceae) and Hemlock species (due to Adelges tsugae) undoubtedly has a strong, long term effect on food webs closely associated with these trees and their specific herbivores. The introduction of Anoplolepis gracilipes in Christmas Island and the Seychelles has lead to new associations with scale insects, leading to important tree mortality and long-term changes in forest ecosystems. 34 Conservation impacts 6.08.08. To what extent does the pest occur in habitats of high conservation value (includes all officially protected nature conservation habitats)? Level uncertainty: of Low Medium Low, Medium, High High Rating guidance Low The pest occurs exclusively, or nearly exclusively outside habitats of high conservation value. Examples: In Central Europe, Cameraria ohridella attacks nearly exclusively horse-chestnut, which is an exotic ornamental tree that is rarely found in habitats of high conservation values. The Potato Spindle Tuber Viroid is found nearly exclusively in agricultural and horticultural habitat. Medium The pest occurs only occasionally in habitats of high conservation value or, if it occurs commonly, no major host is an important component of these habitats (e.g. dominant or keystone species, ecological engineers, etc.). Examples: Lilioceris lilii in North America may be found in protected areas, but its hosts (Lilium spp.) cannot be considered as important components of these protected habitats. Phyllonorycter robiniella is restricted to Robinia pseudoaccacia, which occurs occasionally in protected areas in Europe. However, the host is an alien species and, so, is not an important component of the protected habitats. High The pest occurs commonly in habitats of high conservation value and at least some major hosts are important ecological components of such habitats (e.g. dominant or keystone species, ecological engineers, etc.) Examples: Adelges tsugae attacks hemlock species in nature reserves and national parks, where its hosts are keystone species. Cryphonectria parasitica has nearly eradicated American chestnut, a keystone tree species of several forest ecosystems in Eastern America, including in protected areas. 6.08.09. To what extent does the pest cause harm to rare or vulnerable species (includes all species classified as rare, vulnerable or endangered in official national or regional lists within the PRA area)? Level uncertainty: of Low Medium Low, Medium, High High 35 Rating guidance Low The pest has no rare or vulnerable species as hosts. Examples: Agrilus planipennis is restricted to Fraxinus spp But, so far, none of these species are considered to be rare or vulnerable in North America. Diabrotica virgifera attacks mainly maize and some grasses in Central Europe, none of which are rare or vulnerable. Medium The pest has rare or vulnerable species as minor hosts. “Minor hosts” means that, if they have already been in contact, severe damage has never been observed on these hosts. If they have never been in contact, there is indication that the development on these hosts is less favourable. Examples: In North America, no major host of Lymantria dispar is rare or vulnerable. However, the pest is so polyphagous that, during outbreaks, the chance that it will feed on rare woody species is high. High The pest has rare or vulnerable species as major hosts. “Major hosts” include all hosts on which severe damage has been observed, i.e. damage for which the species has gained its pest status. If the pest and the host have never been in contact in the field, laboratory observations suggest that damage may be as high as on its recognised major hosts. Examples: In North America, one of the major hosts of Adelges piceae is Abies fraseri, which is classified as a vulnerable species by the IUCN. In Florida, Cactoblastis cactorum attacks several endangered Opuntia spp. and Aulacaspis yasumatsui threatens the survival of several rare and endangered cycad species. Final rating: - Each of the three impact categories will be scored with the highest indicator score within its category - A final rating is obtained as follows: • Massive: 3 x High • Major: 2 x High and 1 x Medium • Moderate: 1 x High and at least 1 x Medium or 2 x High and 1 x Low • Minor: 1 x High and 2 Low or 2 or 3 x Medium • Minimal: Maximum 1 x Medium, all others Low 36 6.3 Questions for pest plants Q6.08: How important is the environmental impact caused by the plant within its current area of invasion? (former question 2.6) N/A, Minimal, minor, moderate, major, massive General Concept: In this question we rate the current environmental impact in other invaded regions that can be used as an indicator for determining the potential environmental impact in the PRA area (Q. 6.09). If the species has not invaded any other area, or if the invasion is too recent and too little is known about its ecology in the invaded areas, this question cannot be answered properly, assuming that no additional investigations can be undertaken during the time available for producing the PRA. The assessor may also choose to answer these questions based on well-studied closely-related species or on data for the target species from the region of origin. Although the concept of the “environmental impact” of a native species on native biodiversity and ecosystems is debatable, in some cases recently expanding native species clearly have an environmental impact, resulting from climate change, habitat change, change in disturbance regime or ecological mismanagement (e.g. various weeds such as Canada thistle are now expanding in their native range, etc.). Nevertheless, the assessor should take into account that the environmental impact of a pest in its region of origin is often a very poor predictor of potential impact in regions where it has been introduced. In particular, the absence of any obvious environmental impact in the region of origin should not be considered as a predictor for a low impact in a new area. When data on impact are available in several invaded regions, priority should be given to impact observed in regions that are most closely related, geographically and eco-climatologically, to the PRA region. However, data from other regions should not be excluded. For example, when performing a PRA on an invasive plant for the entire Europe, data on impact already observed in Europe should be given priority, but information from other regions should also be provided. In any case, the assessor should specify the region where the information on impact has been gathered. 5.08.0A Based on the above, do you consider that the question on the environmental impact caused by the pest within its current area of invasion can be answered? If Yes: Go to 6.08.01 If No, but information is available for the native area of the plant, Go to 6.08.01. If No: Go to 6.09.0C, answer N/A for 6.08 The plant has to be assessed for three categories of impact using several indicators that need to be rated. The precise region (and whether invaded or native) and the species (target species or closely-related species) for which the question is answered should be clearly described by the assessors. 37 The subquestions to be answered are organized as follows: Negative impact on native biodiversity 6.08.01. To what extent does the plant cause a decline in native species populations and changes in communities of native species? 6.08.02. To what extent does the plant hybridize with native species? Alteration of ecosystem processes and patterns 6.08.03. To what extent does the plant cause physical modifications of habitats? 6.08.04. To what extent does the plant cause changes to nutrient cycling and availability? 6.08.05. To what extent does the plant cause modifications of natural successions? 6.08.06. To what extent does the plant disrupt trophic and mutualistic interactions? Conservation impacts 6.08.07. To what extent does the plant occur in habitats of high conservation value? 6.08.08. To what extent does the plant threaten rare or vulnerable species? For each of the indicators, a rating is given based three choices: Low, Medium or High. Information is provided for each indicator on the meaning of these scores. For each answer, the associated uncertainty should also be assessed, the possible options are Low, Medium or High: Low: the assessor has low uncertainty that the rating is correct (i.e. the impact has been studied and measured, or the invasion status and bio-ecological characteristics of the plant as well as the characteristics of the invaded habitats allow the assessor to be highly confident of the accuracy of the rating). Medium: The assessor has moderate uncertainty that the rating is correct (i.e. the impact has been studied but some contradictory results have been identified, or the invasion status and bio-ecological characteristics of the plant as well as the characteristics of the invaded habitats allow the assessor to be moderately confident of the accuracy of the rating). High: The assessor has high uncertainty that the rating is correct (i.e. the impact has been studied but the results are contradictory, or the invasion status and bio-ecological characteristics of the plant as well as the characteristics of the invaded habitats do not allow the assessor to be moderately confident of the accuracy of the rating). Negative impact on native biodiversity Note 1: The word “native” in “native species” or “native biodiversity” throughout Questions 6.08 and 6.09 should be understood in a broad sense, 38 i.e. it should also include species that have been naturalised for centuries and that play an important role in the ecosystems or local cultural heritage, such as walnut (Juglans) or chestnut (Castanea) in Europe. The assessor may also include other, more recently introduced beneficial organisms such as exotic plants that play a role in ecosystem services, e.g. plants used against erosion. Note 2: If possible, all mechanisms of impact on native biodiversity should be considered, but only the mechanism providing the highest score and lowest uncertainty is kept for the scoring of the indicators. Mechanisms of impact may include, among others: Competition with native vegetation for limiting resources: Invasive plants are, simply by occupying a large amount of space in invaded habitats, expected to impose a significant impact on the native vegetation through competition for space, light, water and nutrients. For example, the tall and densely growing alien Fallopia species shade out native plant species. Allelopathy: Allelopathy is defined here as a chemically mediated interference competition between co-occurring plant species, including both direct effects of the chemicals and indirect effects of the chemicals that are mediated by the soil microbial community or other biota. Allelopathy is considered as an important mechanism for the invasion success of various alien invasive species, including Ailanthus altissima, Solidago canadensis or exotic Fallopia species. Impact of vegetation changes on higher trophic levels: Changes in plant communities also alter communities at higher trophic levels. For example, because alien Fallopia species are poorly colonized by resident invertebrate herbivores, invasion by Fallopia species reduces diversity and productivity of invertebrate communities, and, as a consequence, the fitness and density of vertebrates that rely on invertebrates as food source. Changes of ecosystem processes: Change of ecosystem patterns and processes (as described in subquestions 6.08.03 to 6.08.06 below) may indirectly affect native vegetation. For example, increased nitrogen availability caused by nitrogen-fixing alien species such as Robinia pseudoacacia and Acacia may reduce the competitive performance of local plants and favour others. Also, changes in fire regime and pollination services may have serious impacts on native community structures. Physical and chemical modifications of habitats may also have an impact on invertebrate and microbial soil communities. Disease vector: Alien plants can act as a vector of plant diseases affecting native vegetation. For example, in Europe, the sudden oak death Phythophtora ramorum is spread mainly by the trade of exotic ornamentals such as Viburnum spp. and Rhododendron spp. Pesticide use: An intensive use of non-specific pesticides over wide areas may affect native biodiversity, in particular when used in natural or semi- 39 natural habitats (e.g. forests, wetlands). For example, glyphosate used to control invasive Fallopia spp. has lethal effects on amphibians. Hybridization: Hybridization between an alien and a native species or subspecies may affect the genetic integrity of native species or sub-species. For example, the Spanish Bluebell Hyacinthoides hispanicus successfully hybridizes with the native bluebell Hyacinthoides non-scripta in the UK 6.08.01. To what extent does the plant cause a decline in native species populations and changes in communities of native species? Level uncertainty: of Low Medium Low, Medium, High High Rating guidance Low The decline in native species populations and changes in the composition and structure of the communities of native species has been studied but not observed. If no study has been carried out to determine the level of impact, according to the information available on the invasion status and bio-ecological characteristics of the plant as well as on the characteristics of the invaded habitats, a decline in native species is unlikely. In particular it can be assumed that species that never build large and dense populations have low impacts on native species. Examples: Oxalis stricta is found in disturbed or man-made habitats without making dense populations, suggesting that it has a very limited effect on native species. Ambrosia artemisiifolia mainly colonises bare soils and is unlikely to outcompete other plant species. The impact of the invasive seaweed Sargassum muticum on a low intertidal macroalgal assemblage was assessed at a rocky shore in Spain and was found to be negligible. Medium A decline has been observed in native species populations and/or change in the composition and structure of the communities of native species, but the decline or change is not persistent and is limited in area. If no study has been carried out to determine the level of impact, according to the information available on the invasion status and bio-ecological characteristics of the plant as well as on the characteristics of the invaded habitats, the impact level is considered to be medium. In particular species that are able to build large and dense but not persistent populations have a medium impact on native species. Examples: Senecio inaequidens occasionally invades semi-natural areas in dense populations but mainly in open areas because it is a relatively weak competitor. Azolla filiculoides forms dense monospecific mats of floating plants that can eliminate submerged plants and algae and reduce populations of animals beneath the mats, but these effects tend to be transient and well localised 40 High A decline has been observed in native species populations and/or changes in the composition and structure of the communities of native species, and the impact is likely to be widespread within the habitats occupied by the species and persistent at least if no management option is taken. If no study has been carried out to determine the impact, according to the information available on the invasion status and bio-ecological characteristics of the plant as well as on the characteristics of the invaded habitats, the impact level is considered to be high. In particular it can be assumed that species with a known ability to build large, dense and persistent populations have high impacts on native species. Examples: Crassula helmsii and Ludwigia grandiflora form dense and persistent populations in water bodies, strongly competing with native species. Fallopia japonica produces large monopecific populations that cause local decline of native plants. In Florida, Melaleuca quinquenervia forms very dense stands, reducing plant and wildlife diversity. In Australia, Mimosa pigra, by converting open sedge wetland to shrubland, caused the loss of native plant and animal communities. Heracleum mantegazzium reduces plant species diversity as compared to non invaded areas in the Czech Republic. 6.08.02. To what extent does the plant hybridize with native species? Level uncertainty: of Low Medium Low, Medium, High High Rating guidance Low Hybridization with native species has been searched but has not been observed. If no study has been carried out, then hybridization with native species is considered to be very unlikely to occur (e.g. no taxonomically closely-related native species occur in the invaded region or hybridization is never observed in this taxonomic group). Examples: There is no European congeneric species of Pueraria lobata and, thus impact by hybridization with native species in Europe is not possible. Prunus serotina has been present in Europe for a long time, where many native Prunus spp. occur, but hybridization has never been observed Medium Hybridization with native species has been observed in the field or in the lab, but the hybrid has a lower fitness and does not replace the native species. If no study on hybridization has been carried out, hybridization is considered possible because of the presence of taxonomically closely-related species in the invaded area belonging to genera in which hybridization has been observed. Examples: In North America, the European Lythrum salicaria may hybridize with the local L. alatum and, although pollen transfer result in much lower seed set than conspecific pollination, this may still 41 have an effect on populations on the native species. High Hybridization with native species has been observed in the field and the hybrid has a high fitness and is replacing, or is able to replace the native species. Examples: Very successful hybrids include, for example, Spartina alterniflora X S. foliosa in the San Francisco bay or Hyacintoides hispanica X H. non-scripta. The hybrid Populus x canadensis threatens Populus nigra. The European shrub Crataegus monogyna, naturalized in Canada, causes abortion of 97% ovules of native Crataegus punctata by fertilizing with its own pollen, hence drastically reducing seed set of the native species. the Spanish Bluebell Hyacinthoides hispanicus successfully hybridizes with the native bluebell Hyacinthoides non-scripta in the UK, Alteration of ecosystem patterns and processes Note: Only the impact on natural or semi-natural habitats should be considered when assessing the impact on ecosystem processes and patterns. However, natural and semi-natural habitats have to be considered in a broad sense, i.e. every habitat that is not under constant human management. It includes all EUNIS habitat types 1 (http://eunis.eea.europa.eu/habitats-codebrowser.jsp), except I (Regularly or recently cultivated agricultural, horticultural and domestic habitats) and J (Constructed, industrial and other artificial habitats). For example, grasslands that are regularly mown are included as well, but not those that are repeatedly re-seeded. 6.08.03. To what extent does the plant cause physical modifications of habitats (e.g. changes to the hydrology, significant increase of water turbidity, light interception, alteration of river banks, changes in fire regime, etc.)? Level uncertainty: of Low Medium Low, Medium, High High Rating guidance Low The physical modification of habitats has been studied but not observed. If no study has been carried out to assess the impact, according to the information available on the invasion status and bio-ecological characteristics of the plant as well as on the characteristics of the invaded habitats, a physical modification of habitats is unlikely. Examples: Ambrosia artemisiifolia is very unlikely to cause physical modification of habitats. Medium A physical modification of habitats has been observed but the impact is not persistent and limited in area. If no study has been carried out to assess the impact, according to the information 42 available on the invasion status and bio-ecological characteristics of the plant as well as on the characteristics of the invaded habitats, the impact level is considered to be medium. Examples: Azolla filiculoides forms dense monospecific mats of floating plants that reduce light interception and photosynthesis for submerged plants. However, these dense populations tend to be transient and well localised. High A physical modification of habitats has been observed and the impact is likely to be widespread within the ecosystem where the species is present and persistent if no management option is undertaken. If no study has been carried out to assess the impact, according to the information available on the invasion status and bio-ecological characteristics of the plant as well as on the characteristics of the invaded habitats, the impact level is considered to be high. Examples: Eichhornia crassipes blocks waterways. Hydrocotyle ranunculoides alters the physic-chemical properties of water. Fallopia japonica causes erosion of river banks. 6.08.04. To what extent does the plant cause changes to nutrient cycling and availability (e.g. significant changes in nutrient pools in topsoils or in water)? Level uncertainty: of Low Medium Low, Medium, High High Rating guidance Changes in nutrient cycling have been studied but not observed. If Low no study has been carried out to assess the impact, according to the information available on the invasion status and bio-ecological characteristics of the plant as well as on the characteristics of the invaded habitats, a change in nutrient cycling is unlikely. Examples: Oxalis stricta is found in disturbed or man-made habitats without making dense populations, and, thus, it is unlikely to change nutrient cycles and availability in semi-natural ecosystems. Medium Changes in nutrient cycling have been observed but the impact is not persistent and limited in area. If no study has been carried out to assess the impact, according to the information available on the invasion status and bio-ecological characteristics of the plant as well as on the characteristics of the invaded habitats, the impact level is considered to be medium. Examples: Lemna spp. may temporarily modify water nutrients. Azolla filiculoides can form dense floating monospecific mats at the surface of water bodies that reduce gas exchanges, causing the 43 predominance of respiratory activities and the reduction in dissolved oxygen in water beneath the mats. However, these dense populations tend to be transient and well localised. High Changes in nutrient cycling have been observed and the impact is likely to be widespread within the ecosystem where the species is present and persistent if no management option is undertaken. If no study has been carried out to assess the impact, according to the information available on the invasion status and bio-ecological characteristics of the plant as well as on the characteristics of the invaded habitats, the impact level is considered to be high. Examples: Robinia pseudoacacia, Acacia spp. and Lupinus polyphyllus increase nitrogen soil content. Carpobrutus spp. modify soil organic contents because of low decomposition rate. Invasive nitrogen-fixing plants and trees that produce dominant populations are likely to score high. 6.08.05. To what extent does the plant cause modifications of natural successions (e.g. acceleration or temporary freezing of successions)? Level uncertainty: of Low Medium Low, Medium, High High Rating guidance Low A modification of natural successions has been studied but not observed. If no study has been carried out to assess the impact, according to the information available on the invasion status and bio-ecological characteristics of the plant as well as on the characteristics of the invaded habitats, a modification of natural successions is unlikely. Examples: Ambrosia artemisiifolia rarely establishes in natural plant communities, except on bare soil. Therefore, it is highly unlikely that it will modify natural successions. Medium A modification of natural successions has been observed but the impact is not persistent and limited in area. If no study has been carried out to assess the impact, according to the information available on the invasion status and bio-ecological characteristics of the plant as well as on the characteristics of the invaded habitats, the impact level is considered to be medium. Examples: In Central Europe, Acer negundo is a competitive pioneer plant but it is usually replaced in the course of succession by more shade-tolerant species. High A modification of natural successions has been observed and the impact is likely to be widespread within the ecosystem where the species is present and persistent if no management option is 44 undertaken. If no study has been carried out to assess the impact, according to available information on the invasion status and bioecological characteristics of the plant as well as on the characteristics of the invaded habitats, the impact level is considered to be high. Examples: Prunus serotina and Rhododendron ponticum impede the natural rejuvenation of forest trees. Buddleja davidii and Robinia pseudoacacia are highly competitive pioneer plants in their invasive range. They hamper habitat recolonisation by native trees and shrubs. 6.08.06. To what extent does the plant disrupt trophic and mutualistic interactions (e.g. through the alteration of pollinator visitations - leading to a decrease in the reproductive success of native species-, allelopathic interactions, strong reduction of phytophagous or saprophagous communities, etc.)? Level uncertainty: of Low Medium Low, Medium, High High Rating guidance Low A disruption of trophic and mutualistic interactions has been studied but not observed. If no study has been carried out to assess the impact, according to the information available on the invasion status and bio-ecological characteristics of the plant as well as on the characteristics of the invaded habitats, a disruption of trophic and mutualistic interactions is unlikely. Examples: Akebia quinata is poorly attacked by herbivores in Europe, does not have closely related plant species in Europe, reproduces mainly vegetatively and never produces dominant stands. Therefore, it is very unlikely that it significantly disrupt trophic and mutualistic interactions. Medium A disruption of trophic and mutualistic interactions has been observed but the impact is not persistent and limited in area. If no study has been carried out to assess the impact, according to the information available on the invasion status and bio-ecological characteristics of the plant as well as on the characteristics of the invaded habitats, the impact level is considered to be medium. Examples: In Spain, Opuntia spp. modify the number of links between plants and pollinators but the effect on native pollination network properties is limited. High A disruption of trophic and mutualistic interactions has been observed and the impact is likely to be widespread within the ecosystem where the species is present and persistent if no management option is undertaken. If no study has been carried out 45 to assess the impact, according to the information available on the invasion status and bio-ecological characteristics of the plant as well as on the characteristics of the invaded habitats, the impact level is considered to be high. Examples: In Florida, Melaleuca quinquenervia has replaced sawgrass marshes and other vegetation types, dramatically changing the food web of these ecosystems. Rhododendron ponticum’s poor quality litter and densely shaded canopy suppresses decomposition rates and algal production in invaded streams in UK, as well as the availability of resources to consumer assemblages. In North America, the high abundance of the European Lythrum salicaria disrupts pollination of local plant species by pollinators, affecting seed production of the native species. Conservation impacts 6.08.07. To what extent does the plant occur in habitats of high conservation value (includes all officially protected nature conservation habitats)? Level uncertainty: of Low Medium Low, Medium, High High Rating guidance Low The plant occurs exclusively, or nearly exclusively, outside habitats of high conservation value Examples: Oxalis stricta and Setaria verticillata are usually found in disturbed or man-made habitats. Medium The plant occurs only occasionally in habitats of high conservation value or, if it occurs regularly, its competitive effects on native species are moderate in such habitats. Examples: Solidago gigantea only occasionally colonizes high conservation value habitats. Amelanchier lamarckii is found in some high conservation value habitats, but without making dense populations, thus most probably having a moderate impact in such habitats. High The plant occurs regularly in habitats of high conservation value and it competes, or is likely to compete successfully with native species in such habitats. Examples: Carpobrutus spp. and Rosa rugosa form high populations in dune ecosystems of high conservation value, competing with native species in such habitats. Ludwigia grandifolia often colonizes water bodies of high conservation value and form dense populations, impacting the native fauna and flora. 46 6.08.08. To what extent does the plant threaten rare or vulnerable species (includes all species classified as rare, vulnerable or endangered in official national or regional lists within the PRA area)? Level uncertainty: of Low Medium Low, Medium, High High Rating guidance Low The plant has no impact on survival or reproduction of rare or vulnerable native species in the susceptible habitats. Examples: Ambrosia artemisiifolia rarely establishes in natural plant comunities and does not represents a threat to rare or vulnerable species Medium The plant interferes with native rare or vulnerable species resident in the susceptible habitats and may cause a limited population decline of these rare or vulnerable species, but there is no sign that the decline may lead to local extinction. Examples: In North America, Lythrum salicaria interferes with the rare Sidalcea hendersonii but the native plant persists in invaded areas. High The plant directly or indirectly threatens the survival or reproduction of native rare or vulnerable species resident in the susceptible habitats, which may lead to local extinction. Examples: In dunes of the North American Pacific coast the European Ammophila arrenaria eliminates rare species such as Oenothera deltoides ssp. bowellii and Erysimum menziesii ssp. Menziesii. Carpobrotus spp. outcompete 27 taxa with a high patrimonial value in Provence (France). Final rating: - Each of the three impact categories will be scored with the highest indicator score within its category - A final rating is obtained as follows: • Massive: 3 x High • Major: 2 x High and 1 x Medium • Moderate: 1 x High and at least 1 x Medium or 2 x High and 1 x Low • Minor: 1 x High and 2 Low or 2 or 3 x Medium • Minimal: Maximum 1 x Medium, all others Low 47 Q6.09: How important is the environmental impact likely to be in the PRA area? Minimal, minor, moderate, major, massive Verify that, based on Q5.08, an environmental impact is also likely to occur in the PRA area, and, if yes, at a comparable level, using the following questions. For this, answers to the section in the “likelihood of establishment” section should be taken into account: 6.09.0A Taking into account the responses to the relevant questions (on hosts and habitats, climatic conditions, abiotic factors, management methods) in the establishment section, are the conditions in the PRA area sufficiently similar to those in the area of invasion to expect a similar level of impact? If No: the situation regarding environmental impact may be different, the assessor should use the subquestions in Q6.08 and reassess those subquestions concerned by the differences identified between the invaded and the PRA areas. If Yes: Go to next question (6.09.0B) Level uncertainty: of Low Medium High 6.09.0B Does the same native species or community, or the same threatened ecosystem services, occur in the PRA area and, if not, is it known whether the native species or communities, or ecosystem service in the PRA area are similarly susceptible? If No: the situation regarding environmental impact is likely to be different between the invaded and the PRA areas, the assessor should use the subquestions in Q6.08 and reassess those subquestions concerned by the differences identified between the invaded and the PRA areas. If Yes: The situation regarding environmental impact is likely to be similar between the invaded and the PRA areas, the score of Q 6.08 can be given in Q 6.09 as impact elsewhere will be the most reliable criterion to predict the impact in the PRA area. Level uncertainty: of Low Medium High 6.09.0C If the assessor considered that Q6.08 has could not be answered, i.e. the species has not invaded any other area, or if the invasion is too recent and too little is known on its ecology in the invaded areas, and assuming that no additional investigations can be undertaken during the time available for producing the PRA, an environmental impact assessment cannot be properly made using this scheme. Nevertheless, in any case, the assessor should be able to provide his/her opinion on the potential environmental impact in the PRA area. 48 Note: So far PRAs carried out for plants in Europe have only concerned plants that have already been reported to be highly invasive or to have an impact, i.e. plants for which Q6.08 can definitely be answered. However, in the future, PRAs may be done for species that are just escaping from cultivation and have no invasion and impact history (e.g. Acer rufinerve in Belgium). To assess these particular cases, an additional set of questions or even another assessment approach may be needed. 49 7 Scoring systems for additional effects and conclusion As noted in the introduction, the evaluation of the following questions may not be necessary if the responses to question 6.04 and 6.05 are "major" or "massive" or any of the responses to questions 6.06, 6.09 and 6.11 is “major" or "massive” or "very likely" or "certain", and you can go to 6.16 unless a detailed study is required or the answers given to these questions have a high level of uncertainty. The previous questions about additional effects (2.11) has been incorporated in question 6.02. Old question: 2.12 How likely are control measures to disrupt existing biological or integrated systems for control of other pests or to have negative effects on the environment? impossible, very unlikely, unlikely, moderately likely, likely, very likely, certain Level of Low Medium High uncertainty: New Question 6.12 To what extent is the pest likely to disrupt existing biological or integrated systems for control of other pests? Minimal extent, minor extent, moderate extent, major extent, massive extent Level of Low Medium High uncertainty: Old question 2.13 How important would other costs resulting from introduction be? Note: costs to the government, such as project management and administration, enforcement, research, extension/education, advice, publicity, certification schemes; costs to the crop protection industry. minimal, minor, moderate, major, massive Level of Low Medium High uncertainty: New Question 6.13 How great an increase in other costs resulting from introduction is likely to occur?? Note: This is evaluated in comparison with total production costs, see q. 5.05. Other costs include costs to the government, such as project management and administration, enforcement, research, extension/education, advice, publicity, certification schemes; costs to the crop protection industry. Level uncertainty: of Low minimal, minor, moderate, major, massive Medium High Rating guidance: 50 Minimal: no increase of costs expected. Minor: other costs are negligible. Moderate: other costs are limited but cannot be neglected. Major: other costs are substantial. Massive: other costs are very expensive. Old question 2.14 How likely is it that genetic traits can be carried to other species, modifying their genetic nature and making them more serious plant pests? impossible, very unlikely, unlikely, moderately likely, likely, very likely, certain Level of Low Medium High uncertainty: Old question 2.15 How likely is the pest to cause a significant increase in the economic impact of other pests by acting as a vector or host for these pests? Impossible/very unlikely, unlikely, moderately likely, likely, very likely/certain Level of Low Medium High uncertainty: 6.14 How great an increase in the economic impact of other pests is likely to occur if the pest can act as a vector or host for these pests or if genetic traits can be carried to other species, modifying their genetic nature? Level uncertainty: of Low minimal, minor, moderate, major, massive Medium High Rating guidance: Minimal: no increase of costs expected. Minor: other costs are negligible. Moderate: other costs are limited but cannot be neglected. Major: other costs are substantial. Massive: other costs are very expensive. Conclusion of the assessment of economic consequences 6.15 With reference to the area of potential establishment identified in Q 3.08, identify the areas which are at highest risk from economic, environmental and social impacts. Summarize the impacts and indicate how these may change in future. minimal, minor, moderate, major, massive Level uncertainty: of Low Medium High 51 References EPPO (2008) Eichhornia crassipes. EPPO Bulletin 38, 441-449. DEFRA (2005) UK Non-native organism risk assessment scheme, user manual. A. Ricciardi & J. Cohen (2007) The invasiveness of an introduced species does not predict its impact. Biological Invasions 9, 309-315. J. Bremmer, T. Soliman, M. Kenis, U. Schaffner, M. Mourits, W. v. d. Werf & A. G. J. M. Oude Lansink (2009) Review of impact assessment methods for pest risk analysis. LEI, The Hague. 52 Annex 1 Matrix model for qualitative economic impact assessment The matrix model combines the answers of the questions about economic impact assessment pairwise. The maximum rule is applied which means that the higher risk rating from the two questions is taken when combined . Whether questions 6.12, 6.13 and 6.14 are answered depends on the answers to the questions 6.06, 6.09 and 6.11 are major or massive. 53 Annex 2 Decision tree to classify products on the basis of yield fluctuations Is the crop grown under protected cultivation? yes Yield variation is low no Are the products sold per number (high quality products) or per kg (bulk )products)? high quality . yes bulk Does the production process take more than one year? Is the product a fruit? no no Yield variation is high yes Yield variation is moderate 54 Annex 3 Decision tree for indirect effects Introduction The qualitative economic impact assessment scheme as presented in Hammamet focuses on the direct impacts to producers (Questions 5.01-5.05), the consequences of an export ban (Question 5.06) and the extent to which direct losses can be borne by producers. One question (5.07a) assesses the potential effects on consumers. However, there is still a need for more guidance to make the indirect effects more explicit and easier to assess. In most cases of major or massive direct economic impacts, indirect effects will occur. Farmers and growers will try to compensate for their losses, either to other producers or to customers or both. Even in cases when farmers are able to transfer most of the losses to others, this does not necessarily mean that the other parties suffer substantial losses. This depends on a number of factors: 1. If producers shift to growing alternative products, it is important to consider the size of both the infested and the alternative market. In most cases, farmers tend to grow products with a comparable added value per ha, and which can be grown without large investment. A shift to products with a higher added value per ha can have large consequences for existing growers of this product. However the acreage of products with a high added value is lower than the area of products with a low added value. For example, an arable farmer who converts 10 ha potatoes to 10 ha bulbs is likely to cause much more trouble to other bulb growers through competition than vice versa. However, in most cases, arable growers include other arable products and bulb growers include other bulb products in their rotation. 2. If producers are able to transfer a large proportion of the impacts to consumers, in only a limited number of cases, consumers will experience higher prices and a reduced availability of the product. Products with a low consumer responsiveness are mostly bulk goods, which are grown at a large scale, such as potatoes, cereals, maize etc. If these products are only affected in a certain area, the product can be imported from other countries. In some cases an import ban will be opposed to prevent the mixture of healthy imported products with infested domestic products. A (potential) example is the market for wood products in Portugal threatened by the Pinewood Nematode. A combination of an export ban and an import ban in the same country will totally separate internal and external markets. If there are substantial export or import volumes (compared to domestic production), consumers are likely to experience changes in prices. However, this will only occur in very exceptional cases. Products with a higher added value normally have higher consumer responsiveness. This is partly because these products are relatively more of a luxury which implies that consumption can be postponed and partly because consumers have the opportunity to shift to alternative products (carnations instead off roses). Consumers are therefore more vulnerable when niche market products are affected. These products include those which are grown at a limited scale for special purposes: flowers for funerals, plants grown for medical purposes etc. 55 The following aspects need to be addressed in the decision tree: - Type of indirect effect. Two types can be distinguished: effects on producers in the same agricultural/horticultural sector and effects on consumers. It must be noted that the PRATIQUE quantitative economic impact assessment model only assesses the effects on consumers. This is inherent to the chosen methodology, partial equilibrium modelling, which only estimates changes in supply, demand and prices of the product at risk. - Magnitude. It is important to distinguish between the extent to which affected producers are able to compensate for direct effects and the extent to which other groups involved (either producers or consumers) experience negative impacts. It is possible that even if a substantial part of a massive impact can be borne by producers or consumers, the size of this group may be so large that individual producers and consumers do not experience any significant change on product prices. The proposed decision tree is presented in Figure 1 and has the following structure: 1. The decision tree starts with a question that determines whether an analysis of indirect impacts is appropriate. The criterion is that the net short term economic impacts caused by yield losses, additional production costs or an export ban should at least be major. 2. The second aspect to consider is the short term economic effect of an export ban when products at risk may be sold in the domestic market leading to lower prices. A drop in prices can be reduced if alternative markets for the crop are available. If this is not the case, producers will look for alternative products to grow. 3. The third aspect takes into account consumer responsiveness (also known as consumer price elasticity). If consumer responsiveness is low, e.g. for staple crops like potatoes, consumers accept higher prices, do not shift to alternative products or postpone consumption and the impacts are mainly borne by consumers. A low consumer price elasticity implies that, if the price increases by more than 1%, the supply will decrease by 1%. For products with a low consumer price elasticity, the price increases will only be experienced by consumers of niche market products and not in other cases. 4. The fourth aspect deals with the possibility for producers to shift to other products. The ease with which production can be adjusted depends on: a. the time needed for new crops to reach full production, e.g. one season for potatoes and several years for apples and b. the availability of factors such as labour, land and the investment (in plants for planting, buildings such as glasshouses etc.) which may have to be made to increase production. The decision to shift to other products also depends on factors such as market expectations and the potential for storage of the product until prices rise. Shifting to other crops is easiest in production sectors where several crops are grown in rotation, e.g. arable farming and nursery stock. 56 Examples Drosophila suzukii can cause massive damage to a number of fruit crop crops such as strawberries, raspberries, cherries etc. By applying the decision tree it is clear that this will have indirect impacts. The net economic short term effect is not caused by an export ban. If only a single soft fruit crop would have been affected, consumers could shift to other soft fruits assuming they are available at the same time of year and are equally liked. However, with D. suzukii many soft fruit crops are affected. Therefore consumers have almost no possibility to shift to other products, but they can postpone consumption or decide not to consume it. The question ‘Do consumers have possibilities to use alternatives or to postpone consumption?’ cannot be answered with a clear ‘yes’ or ‘no’. In the case this question is answered with ‘no’, the result is that the consumers mainly bear the indirect impacts. Because this pest is a severe threat, it is likely that prices will increase. If the question is answered with a ‘yes’, the result is that the direct impacts will mainly be borne by the affected producers. Soft fruit production takes more than one year, so shifting to alternatives takes a long period. According to the rating guidance, question 5.07 gets the score ‘moderate’. Xanthomonas axonopodis pv. allii causes major damage to Allium crops (onions). The decision tree can be applied. An export ban is not likely; the economic impact is mainly caused by the damage to the crop itself. Consumers will not use alternatives or postpone consumption. It is not a niche market product. Therefore, it is likely that economic impacts will mainly be borne by consumers. Whether they will experience price effects depends on the yield loss per ha and the size of the affected area compared with the total production area worldwide. According to the rating guidance, the answer to question 5.07 will be rated as ‘minor’. Meloidogyne enterolobii is expected to cause major damage to a wide range of host plants in different families. This complicates the application of the decision tree. Nevertheless, it is clear that the economic impact is not caused by an export ban. The question whether consumers have the possibility to shift to alternatives or to postpone consumption has to be answered for a range of products simultaneously. It is likely that the possibilities are limited. Products are predominantly not niche market products. It is therefore likely that consumers will bear a large part of the economic impact and will experience higher prices. Question 5.07 can be rated ‘minor/ moderate’. M. enterolobii is a polyphagous nematode and and important crop pest that can cause substantially yield losses. It is likely that the higher prices can partly compensate for yield losses. 57 Fig. 1. Decision tree to determine who experiences indirect economic impacts. Is the net economic short term effect major or massive? no Analysis of indirect impacts not necessary yes Is an alternative use of the product possible? no yes Is the net economic short term mainly caused by an export ban? Impacts mainly borne by consumers, but price effects will be experienced in severe cases yes no no No large indirect effects Do consumers have possibilities to use alternatives or to postpone consumption? no Is the product at risk a niche market product? yes Does the producer have possibilities to shift to alternative products? yes Impacts mainly be borne by consumers, and price effects will be experienced no yes Impacts mainly borne by producers in the same sector Impacts mainly borne by affected producers 58