EN    EN EN 
EN    EN  COMMISSION OF THE E UROPEAN COMMUNITIES 
Brussels, 3.12.2008 
SEC(2008) 2887 
  
COMMISSION STAFF WORKING DOCUMENT 
Annex to the 
 
COMMUNICATION FROM THE COMMISSI ON TO THE COUNCIL, THE 
EUROPEAN PARLIAMENT, THE EU ROPEAN ECONOMIC AND SOCIAL 
COMMITTEE AND THE COMMI TTEE OF THE REGIONS 
 
TOWARDS AN EU STRATEGY ON INVASIVE SPECIES 
  
IMPACT ASSESSMENT 
  
{COM(2008) 789 final} 
{SEC(2008) 2886}  
EN 2   EN TABLE OF CONTENTS 
IMPACT ASSESSMENT .......................................................................................................... 4 
1. Procedural issues and consulta tion of interested parties.............................................. 4 
1.1. Policy context............................................................................................................ ... 4 
1.2. Legal context............................................................................................................. ... 4 
1.3. Stakeholder Consultation and expert input .................................................................. 6 1.4. Internal Consultation.................................................................................................... 6  
1.5. Impact Assessment Board............................................................................................ 7 2. Problem Definition....................................................................................................... 7 2.1. IS definition and pathways........................................................................................... 7 2.2. IS in Europe, their environmental an d economic impact and related costs ................. 8 
2.2.1.  General ......................................................................................................................... 8 
2.2.2.  Environmental impact .................................................................................................. 9 
2.2.3.  Economic impact ........................................................................................................ 10 
2.2.4.  Costs occurred ........................................................................................................... 13 
2.3. The International Dimension of IS............................................................................. 16 2.4. Why Action at EU level? ........................................................................................... 16 3. Objectives.................................................................................................................. . 18 
4. Policy options............................................................................................................. 1 9 
4.1. Option A: "Business as Usual" .................................................................................. 19 4.2. Option B: "Maximise the use of existing approaches" .............................................. 21 4.2.1.  Prevention .................................................................................................................. 21 
4.2.2.  Early warning and information .................................................................................. 22 
4.2.3.  Eradication and control measures ............................................................................. 24 
4.3. Suboption B+: Adapting existing legislation............................................................. 25 4.4. Option C: Comprehensive, dedicated EU legal instrument ....................................... 25 4.5. Horizontal issues ........................................................................................................ 2 6 
5. Comparing the options ............................................................................................... 29 6. Conclusions................................................................................................................ 3 5 
7. Monitoring and evaluation ......................................................................................... 37 
EN 3   EN List of Annexes, Support Documents and References............................................................. 38 
ANNEX A - Figures and Tables .............................................................................................. 40 ANNEX B - Relevant EU research projects ............................................................................ 59 ANNEX C - Examples of costs and benefits of IAS policy measures..................................... 62 
EN 4   EN IMPACT ASSESSMENT  
1. PROCEDURAL ISSUES AND CONSULTATION OF INTERESTED PARTIES  
1.1. Policy context  
Invasive Species (IS) present a se rious threat to biodiversity wh ich needs to be addressed if 
the EU is to attain its  target "to halt the d ecline of biodiversity by 2010"1. The 
Sixth Environmental Action Programme (6th EAP) has identified IS as a priority area for 
action. The Communication on Halting the Loss of Biodiversity by 2010 and Beyond2 and its 
associated Action Plan highlight action on IS as a priority object ive and identify the need for 
the Community to develop a comprehensiv e strategy to address the IS threat.  
In relevant conclusions, the Environment Counc il "calls upon the Com mission to assess gaps 
in the current legal, policy a nd economic framework for the prevention of introduction and for 
the control and eradication of invasive alien species ; invites the Commi ssion, in cooperation 
with the Member States, to prepare an EU st rategy and an effective early warning system, 
taking into account biogeographi cal regions, on the basis of th e CBD Guiding Principles on 
Invasive Alien Species, taking into account the Bern Convention European Strategy on 
Invasive Alien Species and recognising the efforts made by relevant Conventions and 
Organisations such as the IPPC and the EPPO"3. The European Parliament “urges the 
development of a comprehensive Community re sponse to the problem of IS, including an 
early warning system, and filling gaps in the legislative framework, including the development of an EU Strategy on IS”
4. The Committee of the Regions5 and the European 
Economic and Social Committee6 have also expressed support  for the Communication and its 
priorities, including those on IS. 
Furthermore the Environment Council conclusion s of 3 March 2008 note the increasing threat 
to biodiversity from IS and s upports action at EU level.  
1.2. Legal context 
The existing EU legislation7 (e.g. Council Regulation 338/97 (Wildlife Trade Regulation), 
Directive 2000/29/EC (Plant He alth Directive), Veterinary Legislation, Council Regulation 
708/2007 (concerning use of alien and locally ab sent species in aquaculture) covering 
                                                 
1 Presidency Conclusions, Goteborg European Council, 15-16 June 2001 
2 COM(2006) 216 
3 Council conclusions on Halting the Loss of Bi odiversity (COM(2006) 216), 18 December 2006 
4 Report on Halting the Loss of Biodiversity by 2010, the Committee on the Environment, Public Health 
and Food Safety, European Parliament, 28.3.2007 
5 Opinion of the Committee of the Regions of 6 December 2006 on the Communication from the 
Commission: Halting the loss of biodiversity by 2010 – and beyond (COM(2006) 216 final), CdR 
159/2006 fin 
6 Opinion of the European Economic and Social Committee of 15 February 2007 on the Communication 
from the Commission on Halting the loss of biodiversity by 2010 - and beyond (COM(2006) 216 final), NAT/334 - CESE 205/2007 fin DE/Ho/hn 
7 For detailed information see report "Scope options for EU Action on IS" see 
http://ec.europa.eu/environment/nature/invasivealien/docs/2006_06_IS_scope_options.pdf 
EN 5   EN partially some different aspect s of IS makes coordinated imple mentation difficult. The table 
below gives an overview of these four instrume nts and their applicability to the IS issue. 
  Council 
Regulation 
338/97  Directive 
2000/29/EC   Veterinary 
Legislation   Council 
Regulation 
708/2007  
Legal basis Article 130 S Artic le 37 Article 37 Article 37 
Ecological impact ///////////////////8      X 
Economic impact       X 
Health (plant)   X    
Health (animal)     X  
Health (human)     //////////////////////   
Special species group       X 
Legal trade X X X X 
Illegal trade         
Hitchhikers         
Border control 
measures in place X X X X 
Assessment procedure established 
  X X  
 
The dark zones represent the gaps which are not covered by current legislation. The /// zones 
show areas of partial coverage . A wider definition of harmful in the context of the Plant 
Health Directive might extend its coverage to ecological, economical and human health 
aspects. It should be noted th at Council Decision 90/424/EEC on e xpenditure in th e veterinary 
field provides for economic support to control cer tain animal diseases, and the veterinary 
legislation dealing with food safety and zoonoses  covers certain human health risks. In the 
framework of the Community An imal Health Policy (CAHP) the animal health legislation 
may be broadened to cover certain animal dis eases potentially transmitted by animals that 
could be identified as invasive species afte r a sound risk assessment and in full compliance 
with OIE/SPS rules and that are not alr eady covered by veterinary legislation.  
In addition, the Nature Directives (Directives  92/43/EEC and 79/409/EEC, Habitats and Birds 
Directives) explicitly tackle IS issues, as they affect the natura l environment. Article 22 of the 
Habitats Directive provides that Member States shall ensure that deliberate introduction into 
the wild of any species which is not native to th eir territory is regulated so as not to prejudice 
the local fauna and flora and, if they consider  it necessary, prohibit their introduction.  Article 
                                                 
8 Annex B of Regulation 338/97 currently lists 4 invasive alien species 
EN 6   EN 11 of the Birds Directive provides that Member States shall see that any introduction of 
species of bird which do not occur naturally in the wild state in the European territory of the 
Member States does not prej udice the local flora and fauna. Article 6 of the Habitats 
Directive sets out Member State obligations in  relation to Special Areas of Conservation 
(SACs) that make up the Natura 2000 protected sites network establishe d under the Directive. 
These obligations include avoiding deteriorat ion of natural habitats and disturbance of 
species, both of which could be driven by IS in specific circumstances.  
1.3. Stakeholder Consultation and expert input 
In preparing this Communication, the Commission sought the views of st akeholders and the 
general public. Four consultation meetings were held with representati ves of Member States 
and with stakeholder organisati ons. To facilitate dialogue and exchanges, a discussion paper  
"Developing an EU Framework for Invasive Alien Species"9 was prepared and posted on the 
DG Environment website, as a background document for the online consultation (see below).  
From 3 March until 5 May 2008 th e Commission carried out a we b-based consultation. This 
public consultation attracted 880 replies which came from 24 EU Member States, overseas 
territories and international contributions. About a quarter of th e replies came from 
organisations and three quarters from individuals. The results of  the consultation indicate that 
the public is in favour of action at EU level,  i.e. an EU Strategy on IS. Furthermore, the 
results suggest that the public supports strongl y the establishment of an Early Warning and 
Information System. In addition, the public  has expressed a need for monitoring and 
assessment and a need to increase efforts for bu ilding up awareness. According to the replies 
the costs and administrative burden are not perceived as an obstacle, and it is considered that 
there are alternatives to replace those IS that  are currently trade commodities. The need to 
develop good collaboration with in dustry is also seen as an important factor. Regulation of 
trade is considered necessary and acceptable in  order to prevent new introductions of IS. A 
full report on the respon ses to the questionnaire, detailing the replies re ceived, can be found at 
http://ec.europa.eu/environment/n ature/invasivealien/index_en.htm  . 
The results of the public consultation, plus the discussion with the Member States' experts and 
stakeholders, have been taken into account when identifying the available options for developing the Commission's response to the probl em of IS. Furthermore, expert input has 
been used. Expertise has been provided through speci alised EU research projects (DAISIE 
and ALARM, see Annex B), through the Euro pean Conference on Invasive Alien Species 
held in Madrid in January 2008, and through DG ENV service contracts for scoping options 
for EU action on Invasive Alien Species (termi nated in June 2006) and for technical support 
to an EU strategy on IS (running from January 2008 until June 2009). 
1.4. Internal Consultation 
A Commission Inter-service Group  (ISG) has been establishe d. The group meets before the 
stakeholder and Member State meetings and the members are invited to attend all the 
consultation meetings. The group will continue it s work during the seco nd phase to pave the 
way for the EU Strategy on IS. 
                                                
 
9 See http://ec.europa.eu/environment/nature/invasivealien/index_en.htm 
EN 7   EN 1.5. Impact Assessment Board 
A draft Impact Assessment was discussed at th e Impact Assessment Board meeting of 9 July 
2008. Following the opinion of the Board, the draft version has been updated to take into 
account the recommendations of the Board, thus the current version of the Impact Assessment 
contains the improvements sought. More specifi cally, the policy options have been reworked 
in such a way as to clarify the difference between  the identified options compared to the status 
quo and business as usual option, but also to take  into account the different responses needed 
depending on how IS enter and spread thr oughout the EU. The Impact Assessment report 
shows clearly who needs to b ear new responsibilities and cost s under each of the examined 
options, while it indicates the extent to wh ich the options depend on future financing.  
The international dimension of IS has been stre ssed further in the current Impact Assessment. 
The report looks at possible approaches to tack ling issues of extra-EU trade and movement of 
IS, while the issue of international cooperation has been signalled and addressed. However, 
more explicit analysis of these poin ts will be done in a subsequent phase. 
As indicated, this Impact Assessment report supports the Communicatio n exploring ways to 
deal with the issue of Invasive Species in the EU including Outermost Regions and Overseas 
Countries and Territories. A de fined policy proposal will be  developed during the coming 
year(s), providing a comprehensive response to the IS problems identified. Further work in 
the following period has been planned already, aiming to identify the elements that will be part of the comprehensive EU strategy. The wo rk will examine thoroughly the costs to be 
borne by the various economic and social groups, and it will also help to define the best possible and most cost-efficient way to respond to the IS challenges, while administrative and 
implementation costs for public administrations and private parties/s ectors will also be 
explored. These analyses will form part of th e forthcoming Impact Assessment report that will 
accompany the future proposal. As financing w ill be needed for implementing actions to 
tackle IS, the report will also address thorough ly the financial needs for putting in place and 
implementing the actions that will be advocated by the Commission proposal. 
2. PROBLEM DEFINITION  
2.1. IS definition and pathways 
"Alien species" are species which are introdu ced outside their natural past or present 
distribution area and succeed in surviving and subsequently reproducing. "Invasive (Alien) 
Species" are species whose introduction and/ or spread threatens biological diversity10. 
Invasive species (IS) may arrive and enter a new region through three broad mechanisms: 
importation as a commodity, introdu ction via a transport vector, a nd/or natural spread from a 
neighbouring region where the spec ies is itself alien. These three mechanisms result in six 
principal pathways: release, escape, cont aminant, stowaway, corridor and unaided.  
Figure 3 in Annex A identifies five pathways associated with human activity either as 
commodities (release and escape), contaminan ts of commodities, stowaways on modes of 
transport and opportunists exploiting corridors resulting from transport infrastructures, while a sixth pathway highlights invasive species that may arrive unaided in a region as a result of 
                                                
 
10 CBD Guiding Principles (C BD Decision COP VI/23) 
EN 8   EN natural spread following a primary human-medi ated introduction in a neighbouring region. 
The different regulatory approaches for each pa thway are also illustrated. Invasive species 
transported as commodities may be introduced as  a deliberate release or following an escape 
from captivity or containment. However, ma ny invasive species are not intentionally 
transported but arrive as a contaminant of a commodity, for example pathogens and pests. 
Stowaways (or hitchhikers) are directly a ssociated with human transport but arrive 
independently of a specific commodity, for exam ple organisms transported in ballast water, 
cargo and airfreight. The corridor pathway (e.g.  highways, railways, canals) highlights the 
role transport infrastructures play in the introduction of invasive species. The unaided pathway describes situations wher e natural spread results in an invasive species coming into a 
new region from a donor region where it is also alien.  
The marine environment is well suited to dispersa l. This is especially true for those species 
living in the water column itself, but bottom dw ellers may also release propagating units into 
the water, which then disperse widely with the water currents. The marine environment is 
relatively poorly monitored, hen ce the probability of discovering an alien species before it has 
established a permanent population is small (Ruiz and Carlton, 2003). While only a small 
fraction of the marine species introduced outside  their native range are able to thrive and 
invade new habitats (Mack et al, 2000), their impact can be dramatic (Molnar et al, 2008). 
Figures 4 and 5 in Annex A demonstrate that wh ile there is already a considerable stock of 
invasive species present in Europe, the probl em will grow exponentially due to increased 
entry via expanding trade activities. 
Furthermore, on the one hand side the major ec onomic sectors act as sources of invasive 
species in Europe and on the other hand invasi ve species cause significant problems within 
these sectors (see table 4 in Annex A). The pr oportions of different taxonomic groups listed in 
four trade categories are shown in Figures 9-12 in Annex A while Table 6 in the same Annex 
presents a list of pathways of IS introductions in Europe with descriptions for assessment of 
pathways.  
2.2. IS in Europe, their environmental a nd economic impact and related costs 
2.2.1.  General 
Biological invasions are recognised as a key component of global environmental change, 
often resulting in significant damage to the ec onomic value, biological diversity and function 
of invaded ecosystems (Wittenberg and Cock 2001). Numerous alien species, many introduced only in the last 200 years or so, ha ve become successfully established over large 
areas of Europe (Hulme 2007). Future global biodiversity scenarios highlight potentially 
dramatic increases in biologi cal invasions in European ecosystems (Sala et al. 2000). 
Interacting effects thro ugh rising atmospheric CO
2 concentrations, warmer temperatures, 
greater nitrogen deposition, alte red disturbance regimes and in creased habitat fragmentation 
may facilitate further inva sions (Vilà et al. 2006). 
Overall, the numbers of alien species invading Eu rope that are known to have an ecological or 
economic impact are, respectively, 1 089 ( 11%) and 1 374 (13%). Many species produce 
multiple impacts; this is a consequence of “casca ding” effects at different levels of ecological 
complexity. Vertebrates are the group with th e highest proportion of  species having a known 
EN 9   EN impact, with the greatest regional spread, and one of the taxonomic groups causing more 
types of impact (see Annex 2 for information about DAISIE11). The main identified costs in 
Europe can be grouped into eradication and cont rol; agricultural and forestry damage; loss of 
commercial fisheries, damage to infrastructu re and, finally, damage to human health.  
2.2.2.  Environmental impact 
Invasive species may have profound environmenta l consequences, exacti ng a significant toll 
on ecosystems (European Commission, 2004) (Box 1). These range from wholesale 
ecosystem changes, e.g. co lonisation of sand dunes by Acacia spp. and extinction of native 
species or threats to endemic coastal plants following expansion of iceplant ( Carpobrotus 
edulis ), to more subtle ecological changes and increased biological homogeneity. For 
example,  rhododendron ( Rhododendron ponticum ) reduces the biodiversity of Atlantic 
oakwoods and the  American mink ( Mustela vison ) is held partially responsible for the decline 
in water vole ( Arvicola terrestris ) populations in the UK. The freshwater Asiatic clam 
(Corbicula fluminea ) is a  phytoplankton feeder, its dense populat ions may affect the structure 
of planktonic communities,  competing with native clams, re ducing fish stocks, and shifting 
primary production to benthic  communities. A subtler but potentially more serious impact of 
invasive species is the possibility of  hybridisation with native species. Hybridisation has 
occurred between alien sika ( Cervus nippon ) and native red ( C. elaphus ) deer, the alien ruddy 
(Oxyura jamaicensis ) and native white-headed ( O. leucephala ) ducks as well as between 
native and alien oaks ( Quercus spp). Hybridisation may  introduce maladaptive genes to wild 
populations or result in a vi gorous and invasive hybrid. 
Box 1. List of IS main negative ecological impacts  
• Competing with other organisms : plants like Japanese knotweed ( Fallopia japonica) or 
Giant hogweed ( Hercleum mantegazzianum ) compete with native plants, causing changes 
to habitat structure 
• Predating  on native organisms: Predation by American mink ( Mustela vision ) has caused 
significant population declines of gr ound nesting birds and small mammals  
• Hybridising  with a related species or variety, such as the North American grass Spartina 
alterniflora which hybridised with the European Spartina maritima and produced the very 
invasive hybrid Spartina anglica , which has radically changed coastal mudflat habitats in 
Great Britain, Denmark and Germany 
• Causing extinction  of native species: crayfish plague ( Aphanomyces astaci ) is known to 
threaten local populations of na tive crayfish with extinction  
• Being toxic : toxic algae blooms are caused by  alien phytoplankton such as Chattonella 
verruculosa  
• Being a reservoir for parasites  or a vector  for pathogens: rainbow trout is a host for the 
salmon parasite Gyrodactylus salaris  
                                                 
11 DAISIE, Delivering Alien Species Inventory for Europe see http://www.eur ope-aliens.org/index.jsp 
EN 10   EN • Disrupting pollination : Impatiens glandulifera competes for pollinators such as 
bumblebees with the native rive rbank species, and so reduces seed  set in these other plants  
• Altering energy and nutrient flows : alien plants, such as Robinia pseudacacia , alter 
nutrient availability via nitrogen-fixing 
• Altering the local food web : when appearing in large densities the Asian date mussel 
(Musculista senhousia ) can shift the community from suspension-feeding to primarily 
deposit-feeding 
• Altering the composition and functi oning of habitats and ecosystems : Water hyacinth 
(Eichhornia crassipes ) changes water flow by overgro wing and blocking water bodies.  
Source: Braat L. & P. ten Brink et al. 2008. Cost of Policy Inaction (COPI): The case of not meeting the 2010 
biodiversity target, a study for the European Commission (Annex III by ten Brink, Kettunen & Peralta Bezerra 
on IS) 
2.2.3.  Economic impact 
There are plenty of examples where IS have caused significant dama ge to economic activity 
and where their control or erad ication has entailed significant  costs (see examples in box 2 
and in table 2 in Annex A). In general, the recorded economic impact occurs when ecosystem 
services, i.e. ecosystems' capacity to maintain ma terial flows and processe s that are beneficial 
to human wellbeing, are disrupted by IS. The table below indicates the main IS taxa impacting 
on different ecosystem services. 
Table 1: Main IS taxa impacting on di fferent ecosystem services in Europe 
Type of ecosystem service (ES) affected by IS Main IS taxa causing impact 
Provisioning Services   
Food and fibre  Invertebrates (terrestri al & marine); plan ts (terrestrial); 
vertebrates (terrestrial); fungi 
Fresh water Invertebrates (marine & freshwater); plants (marine & 
freshwater) 
Regulating services   
Water regulation (e.g. flood prevention, timing and magnitude of runoff, aquifer recharge) Invertebrates (marine & freshwater); plants (marine & 
freshwater); vertebra tes (terrestrial) 
Erosion control Vertebrates (terre strial), plants (terrestrial), 
invertebrates (freshwater) 
Water purification / quality maintenance and waste 
management Invertebrates (marine & freshwater), plants (marine & 
freshwater) 
Regulation of human diseases (i.e. IS as a vector for disease) Invertebrates & verteb rates (terrestrial) 
EN 11   EN Fire resistance (change of vegetation cover leading to 
increased fire susceptibility) Terrestrial plants 
Other: human health other than diseases (e.g. 
allergies and injuries) Invertebrates (terrestrial & ma rine); plants (terrestrial) 
Other: destruction of infrastructur e Invertebrates (marine & freshwater) 
Cultural services   
Cultural / natural heritage values, aesthetic / cultural 
value, recreation and ecotourism Plants (terrestrial, freshwate r, marine); invertebrates 
(terrestrial, freshwater, marine ); vertebrates (terrestrial, 
freshwater, marine); fungi 
Supporting services   
Primary production Plants (terrestrial, freshwater, marine); invertebrates 
(marine & freshwater) 
Nutrient cycling Plants (terrestrial , freshwater, marine); invertebrates 
(marine & freshwater) 
Soil / sediment formation Invertebrates (marine & freshwater) 
Other: changes in species dynamics and/or 
ecosystem's food web Invertebrates (marine & freshwater) 
Source: Kettunen M. et al 2008. Technical Support to EU Strategy on IS; Report "Assess ment of the impacts of IS in Europe 
and the EU". 
The recent analysis by Kettunen et al. (2008) of cases where there is evidence of significant 
environmental, social and economic impact in Europe from 125 IS, including the 100 worst IS 
identified in DAISIE, revealed a total of 57 IS  species that are known to negatively affect 
ecosystems’ provisioning services, i.e. the ab ility of ecosystems to provide different goods 
and products (e.g. food, fibre and water) that benefit human we llbeing. The vast majority of 
these impacts (impact of 54 species) are caused by IS having adverse effects on provisioning 
of food , for example IS causing decline in fish  catch, aquaculture, crop and wood production 
or IS with negative effects on liv estock (e.g. livestock health). In addition, in some cases (3 
species), decline in provisioning of water  due to blocking waterways has been recorded (i.e. 
some aquatic exotic plants, such as water hyacinth ( E. crassipes ) and New Zealand 
pigmyweed ( C. halmsii )).  
The above analysis of IS' impact on ecosystem se rvices also shows that IS are known to have 
a negative impact on regulating services such as erosion control, water quality and 
resistance of ecosystems to wild fires . For example, invasive ma mmals can cause erosion by 
burrowing in river banks whilst i nvasive plants may overtake completely native plants that 
play an important role in binding soil with th eir roots (borrowing: e .g. Louisiana crayfish ( P. 
clarkii ) and European rabbit ( O. cuniculus ); competition: Himalayan balsam ( I. 
glandulifera )). Finally, IS can also damage infrastructure  due to burrowing (invertebrates & 
vertebrates) or via thei r root systems (plants). 
According to the same report, most of the identified instances where IS have a negative 
impact on cultural services, i.e. different cultura l, social, recreational and educational values 
of ecosystems, relate to the reduction of recreational use and/or tourism due to invasion of 
non-native species (40 species). This can happen for a number of reasons, including decreased 
EN 12   EN aesthetic value caused by IS invasion, nuisance to  humans and/or recreational activities, and 
impact of IS on human health (see section 4.2.2 above). For example, a number of non-native 
aquatic plants are known to reduce recreationa l use of water bodies by blocking access to 
open water (e.g. Azola sp. and water hyacinth, E. crassipes ). Thick vegetative growth of 
aquatic IS can also hinder fish ing and angling activities. In ge neral, the assessment of IS' 
impact on cultural services, such as the aesthetic value of landscape, is highly subjective. This 
means that any view about the impact of non-na tive species on these serv ices can be either 
positive or negative, depending on the perspective of the person or organisation concerned.  
On the other hand a high number of much-appr eciated pets, game sp ecies and ornamental 
plants and animals in Europe are non-native. These include, for example, common cat ( F. 
cattus ), rhododendron ( R. ponticum ), Japanese deer ( C. nippon ), and ornamental fish used in 
private and public aquaria (Kettunen et al., 2008).  
Box 2: Examples of recorded economic impact resulting from IS and cost of controlling 
them 
Instances of recorded direct economic imp act include the damage caused by Japanese 
knotweed ( Fallopia japonica ) to masonry, pavements, walls, drainage works and native 
riparian communities, increased flood risk and increased cost of land clearance for 
development (where the plant occurs on a development site it can cost tens of thousands of 
pounds to adequately control). In Germany, es timated costs are €5.9-6.6 million/year (plant 
control), €12.3-21.2 million/year (stabilisation of  river banks), €2-7.7 million/year (clearance 
of railways) and €3.5-10.5 million/year (repair of foundations). The Czech Republic spends 
€0.2 million/year on control/containment. In the UK, a 2003 estimate put the cost of removal 
from Britain at £1.56 billion. Specific control costs cover attempted eradication (over €1 078 
million/year) and research on biocontrol (€0.11 million/year). In Wales (UK), the estimated 
annual control costs for one c ounty council were £300 000 (in 1994). 
Another example is the impact of bark stripp ing by grey squirrels ( Sciurus carolinensis ) on 
forestry production. The western corn rootworm ( Diabrotica virgifera ), which was 
accidentally introduced into Serbia  in the 1990s, is a major pest of maize that leads to yield 
losses. Preliminary studies on the potential for establishment of the western corn rootworm 
show that this pest is likely to survive and develop wherever maize is grown in Europe. 
Leaving aside introduced pests and diseases affecting agriculture, alien parasites such as 
Gyrodactylus salaris (an ectoparasite of Atlantic salmon) and Anguillicola crassus 
(swimbladder nematode of eels) ha ve led to dramatic decreases in fisheries sector incomes in 
several Nordic countries. Th e American oyster drill ( Urosalpinx  cinerea ) is a major gastropod 
pest of the cultured oyster industr y as it feeds preferably on oyster spat and is recorded as 
consuming more than half the oyster spat in  certain European estuaries (Cole 1942). The 
muskrat ( Ondatra zibethicus ) and coypu ( Myocastor coypus ), both introduced by the 
European fur industry, damage river banks thro ugh digging and have increased the risk and 
severity of floods in many centr al and southern European count ries. In Italy (1995-2000), the 
removal of over 220 000 coypus cost €2.614 milli on whilst riverbank damage exceeded €10 
million and agricultural damage was almost €1 m illion. Current control co sts available for EU 
Member States total €5.02 million/year (Nethe rlands: prevention/control €0.8 million; East 
Anglia (UK): eradication €0.45 m illion; Italy: combined damage /control costs, €3.77 million).  
Notorious invasive alien weeds cause major economic harm, e.g. Mexican tea ( Chenopodium 
ambrosioides ), knotgrass ( Paspalum paspaloides ), Canadian horseweed ( Conyza canadensis ), 
Bermuda buttercup ( Oxalis pes-caprae ), while other alien plants  act as hosts of plant 
EN 13   EN pathogens e.g. rescuegrass ( Bromus catharticus ) as host for barley yellow dwarf virus and 
wheat stem rust. Invasive alien specie s can also affect human health, e.g. 
phytophotodermatitis through contact with giant hogweed ( Heracleum mantegazzianum ), 
asthma and hay-fever arising from the pollen of annual ragweed ( Ambrosia artemisiifolia ), 
poisoning of humans through consumption of  toxic fruit, e.g. American pokeweed 
(Phytolacca americana ), silverleaf nightshade ( Solanum eleagnifolium ) or leptospirosis 
spread by the brown rat ( Rattus norvegicus ). 
Sources: Kettunen et al. (2008); DAISIE. 
2.2.4.  Costs occurred 
The analysis by Kettunen et al. (2008) reveal s that, in general, the existing evidence on IS' 
economic impact in Europe can be divided into two main categories, i.e. costs of damage and 
costs of control measures. Information on the co st of damage is the most common cost item 
for the negative impact on the agricultural, fo restry and fisheries s ectors resulting from 
invasions of non-native pests, su ch as plant diseases  (fungi), insects an d fouling organisms 
(marine, freshwater and terrestrial invertebrate s). In addition, there are some estimates on the 
damage caused by IS to human health, e.g. tr eatment costs for asthma. Information on the 
monetary resources needed to control IS is available across different  IS taxa and invaded 
ecosystems.  
Based on the information on documented (real & estimated) costs, the total known 
monetary impact of IS in Eu rope amounts to €9.6 billion/year  (Kettunen et al. 2008, see 
Table 2 below). Costs related to the damage  caused or control of terrestrial IS (e.g. 
vertebrates, plants and inverteb rates) form a major part of this estimate. This includes, for 
example, damage caused by pests to agriculture and forestry.  
Given the limited availability of documented cost s, Kettunen et al. 2008 also carried out an 
extrapolation of costs to provide a more compre hensive picture of the real magnitude of the 
potential economic impact of IS in Europe12. The extrapolation has been carried out on the 
basis of information on the area affected by IS and the known range of IS in Europe. The cost 
estimates from identified study areas have been tr ansferred to cover the full current range of 
IS in Europe. As a result the costs of IS can be estimated as €12.7 billion/year. This should 
still be seen as an underestimate for it only co vers a limited number of IS (e.g. extrapolation 
of costs was possible only for 25 of 125 IS consid ered in the analysis). Also, the extrapolation 
is only based on a subset of real IS costs, i.e. it does not cover the lo ss of biodiversity-related 
existence, bequest and option value due to IS invasion. 
                                                 
12 I.e. where information is available on the costs of an IS for a given area (the study area) and where the 
full European range of this given IS is known (from the DAISIE database), costs numbers can be 
created for the full range. This is done by applying the costs insights from known case study areas (i.e. costs per unit area of the study area)  to the wider area impacts by th e IS. These costs numbers assume 
that the level of impact/costs is similar thr oughout the known European range of a given IS. 
EN 14   EN Table 2 Overview of the recorded economic costs (r eal costs & estimates) due to different IS taxa in 
Europe13.  
Taxa / biome of IS SUM of 
known costs in 
EU (million 
EUR / year)  No of 
cases SUM of 
known costs 
in non-EU14 
(million EUR 
/ year ) No of 
cases SUM of 
known costs 
in Europe 
(million EUR 
/ year)  No of 
cases TOTAL 
(million / 
EUR)  
Fungus (freshwater / 
terrestrial) 1505.00 3 0.16 1 -  1505.16 
Freshwater 
invertebrate 99.38 3 20 1 0.99 3 120.37 
Freshwater 
vertebrate -  -  -   
Freshwater plant 3.89 2 -  -  3.89 
Marine invertebrate  1 1 -  36.68 3 37.68 
Marine vertebrate -  -  -   
Marine plant -  -  18.56 2 18.56 
Terrestrial 
invertebrate 786.16 10 -  500.00 1 1286.16 
Terrestrial vertebrate 4290.13 29 -  -  4290.13 
Terrestrial plant 2302.67 23 -  -  2302.67 
Known costs 8988.23 71 20.16 2 556.23 9 9564.62 
Source: Kettunen M. et al 2008. Technical Support to EU Strategy on IS; Report "Assess ment of the impacts of IS in Europe 
and the EU". 
Note: This synthesis is based on the available information on do cumented costs of IS (i.e. without extrapolation of costs). 
(Kettunen et al, 2008 Annex II) 
Table 3 Overview of the recorded economic costs (real costs & estimates) of diff erent IS taxa on different 
economic sectors in Europe.15 
Economic sector & pest taxa Costs of damage (million EUR 
/ year) Costs of control (million 
EUR / year) 
Agriculture*     
Terrestrial plants (weeds) 1050.00 no info 
Terrestrial invertebrates (pests) 735.48 526.72 
Freshwater invertebrates 2.21 0.1 
                                                 
13 see Kettunen et al. 2008 Annexes VI and VII. 
14 Non EU states included are An dorra, Iceland, Liechtenstein, Mo ldova, Monaco, Norway, Russia, 
Switzerland, Ukraine, former Yugoslavian states in the Balkans 
15 See Kettunen et al. 2008 Annexes VI and VII for data origin and references. 
EN 15   EN Terrestrial vertebrates 901.28 no info 
Fungi 1500.00 no info 
Pests non-specified for taxa   198 
Total 4913.79 
Fisheries / aquaculture     
Freshwater invertebrates 118.06 no info 
Marine invertebrates 25.53 no info 
Marine plants 18.56 no info 
Fungi 0.16 no info 
Total 162.31 
Forestry     
Terrestrial plants (weeds) no info 22.7 
Health*     
Terrestrial invertebrates  22.50 1.46 
Terrestrial plants 33.15 2.34 
Total 59.45 
Known costs (million EUR / year) 5135.55 
* The table does not include costs of epidemic animal and human diseases 
Source: Kettunen M. et al 2008. Technical Support to EU Strategy  on IS; report "Assessment of the impacts of IS in Europe 
and the EU" 
Note: This table synthesises the informati on on documented costs of species (i.e. wit hout extrapolation) as relevant to specifi c 
sectors (Kettunen et  al. 2008, Annex 2) 
Kettunen et al. analysed the documented IS econo mic impact by sector (i.e. a specific "subset" 
of the above €9.6 billon), divided into two main categories: (a) cost of damage; (b) cost of 
management and control measures. Accordi ng to these calculations, the known documented 
costs for the agricultural, fisheries, forestry and health sectors amount to €5.1 
billion/year  (excluding the costs of epidemic animal and human diseases). Again this figure 
is based on the documented data and with no attemp t at extrapolation of other gap filling. Like 
the other aggregate cost estimates above, this figur e is likely to be an underestimate of the real 
situation as the forestry-related costs seem clearly to be underrepr esented and no monetary 
values exist for costs attributable to IS in  the tourism sector. The key elements of the 
breakdown of these costs are given below (for  more detail, see the Task 1 report):  
EN 16   EN – Based on available information, IS costs (documented costs)  are highest for the 
agricultural sector  (€4.9 billion/year, of which €4.19 billion/year re lates to damage costs 
and €725 million/year to control costs); 
– Documented information is very limited for fisheries and aquaculture  (estimate of 
€162 million/year in damage costs: no info rmation is available on control costs); 
– The information available is clearly underrepresented for forestry  (no estimate of overall 
damage costs: control measures estimated at €22.7 million/year); 
– The IS cost to the health sector  (excluding cost of epidemic animal and human diseases) 
was estimated at €59.45 million/year  (€55.65 million/year in damage costs and €3.8 
million/year in control costs).  
These analyses are limited to a number of ke y sectors where information is available. 
Although it does not provide a complete picture, it demonstrates that economic damage by invasive species implies significant costs. 
2.3. The International Dimension of IS 
The EU will need to boost support for the prev ention, detection, control and eradication of IS 
in third countries . The Convention on Biological Divers ity has inter alia  urged donors to 
provide, as a high priority, funding for the deve lopment and implementation, at national and 
regional levels, of the in vasive alien species stra tegies and action plans and for the application 
of the CBD Guiding Principles
16. The Environment for Europe Conference agreed to promote 
the implementation of the pan-European Strate gy on Invasive Alien Species developed under 
the Bern Convention17. The European Community can support third countries and regional or 
international activities through its Developmen t Cooperation Instrument  (in particular the 
Environment and Natural Resources Thematic Programme), the European Development Fund 
and the European Neighbourhood Policy Instrument . Member States can provide additional 
support through their own developm ent cooperation instruments. 
2.4. Why Action at EU level? 
Several biological invasions now threatening Europe might have  been prevented by a higher 
level of awareness of invasive  species issues and a stronger commitment to addressing the 
matter, e.g. the spread of the killer alga ( Caulerpa taxifolia ). Current inaction by many, 
though not all countries, is becoming increasingl y disastrous for the region’s biodiversity, 
health and economy (Hulme 2007). European states  should recognise the risk that activities 
within their jurisdiction or control may pose to other states as a potential source of invasions 
and take appropriate individual and cooperative actions to mi nimise that risk. This is 
particularly important within Europe as species  introduced into the territory of one state can 
easily spread to neighbouring states, especi ally with a shared coastline, transboundary 
mountain ranges and international wa tercourses. It is also criti cal with regard to Europe’s 
trading partners. 
                                                 
16 See inter alia CBD COP decisions VI/23 includin g the Guiding principles for the prevention, 
introduction and mitigation of impacts of alien invasive species that threaten ecosystems, habitats or 
species, VIII/27 and IX/4. 
17 Kyiv Resolution on Biodiversity adopted at the 5th Ministerial Environment for Europe Conference. 
EN 17   EN The heterogeneity in the degree to which different European na tions are exposed to biological 
invasions may limit recognition of the risk that activities within  their jurisdiction may pose to 
other nations. Species prioritised for manage ment differ across Europe, which means that 
concerted action should be planne d at sub-regional levels. Finally , a species that is alien in 
one European nation may be native in another. This makes for considerable complexity with 
regard to the development of regulations regarding trade with in Europe. Therefore in the 
current work at EU level the focus is  on the invasiveness of the species.  
Effective control of invasive species has been hampered in  Europe by the lack of: (a) 
monitoring for alien species at frequent enough inte rvals in regions of c oncern; (b) a means to 
report, verify the identificati ons, and warn of new sightings; and (c) risk assessments that 
predict the likelihood of  a particular species  becoming invasive.  
There are several reasons why dealing successfully with IS requires action at EU level: 
(1) IS do not respect borders. An IS outbreak, wh ich is ignored in one Member State, may 
represent a risk for neighbouring countries . Equally, action by one Member State can 
be annulled by inaction across the border. 
(2) IS remain a rapidly increasing threat to  European biodivers ity. Inaction hinders 
achievement of the EU target of halting biodiversity loss. 
(3) The increasing volume of trade contributes to the  spread of IS. Free trade rules are 
perceived by many Member States as a c onstraint on regulating introductions of 
potential IS at the national level. Trade in  goods is the exclusiv e competence of the 
EC. 
(4) The EU dimension is already recognised in the context of existing measures to deal 
with problems in the field of plant and anim al health. In cases where invasive species 
represent a threat to plant and anim al health, there are already overlaps18. 
(5) The EU dimension is clearly demons trated in Council Regulation 708/2007 
concerning the use of alien a nd locally absent species in aquaculture, adopted in June 
2007.  
(6) Experts encourage the Commi ssion to implement a cooperative legal framework at EU 
level to address IS (e.g. Resolution of th e NEOBIOTA conference held in September 
2006 and attended by some 350 European scientists19). The conclusions of the 
European Conference on Invasive Alien Species20 and the outcome of the online 
consultation of the public and stakeholders have also given strong leverage for action 
at EU level.  
                                                 
18 To avoid possible overlaps between the veterinary legislation and the future framework on IS, it is 
necessary to coordinate the development of the CAPH  and the EU Strategy on IS. Therefore, expertise 
on IS would be needed to implement measures within  the CAPH to tackle those IS considered as high 
risk after a careful risk assessment and following th e international framework on animal health (i.e. 
OIE/SPS rules). 
19 Part of the conference resolution: “to complement existing European activities to close gaps in 
pathways, habitats and taxonomic groups in order to build a cooperative legal framework and to address IS at the appropriate level”. 
20 Final Publication of the Conf erence, see http://www.fundacion-
biodiversidad.info/eei/pdf/PUBLICACION%20FINAL/Version%20Ingles/Versioningles.pdf 
EN 18   EN (7) A consistent and coherent policy on IS in the EU will bring additional benefits to the 
fight against IS.  As described under section 1.2, at  the moment there exists a 
patchwork of Community instruments which can partially address the IS issue. In 
many cases import of proven IS continues (e.g. Hydrocotyle ranunculoides  (floating 
pennywort), a water ornamental plant, is c overing water bodies and thus destroying 
water ecosystems and causing problems for the shipping industry). Important pathways, e.g. ships' ballast water, are not  controlled and are allowing invasion of 
further species. 
(8) Certain categories of IS are not  covered at all under the current legislative framework, 
nor can this be done easily simply by modi fying the existing legislation. For organisms 
outside the specified categorie s (mammals, certain birds (subj ect to legislation in force 
to control avian diseases) aquaculture spec ies, vectors of diseases affecting wild 
animals, some plants, some insects, etc. ) there are no Community-backed controls on 
import and export and no restrictions on intra-Community trade and movement. 
(9) The environmental impact of invasive sp ecies tends to be mu ch greater in EU 
Overseas Countries and Territories (OCTs)  and Outermost Regions (OR) than in 
continental Europe. Island biodiversity is ex ceptionally vulnerable to invasion because 
of the long evolutionary isolation of island ecosystems. IS in OCTs and ORs thus have 
a disproportionately high impact on wide r European biodiversity. Socio-economic 
consequences are also greater in remote  territories where livelihoods, culture and 
economic opportunities often depend on biodive rsity and ecosystem services. Climate 
change, in association with other environmental pressures,  is predicted to aggravate 
the situation by disrupting ecosystem f unction and altering sp ecies’ distribution. 
3. OBJECTIVES  
The Communication "Towards an EU Strategy on IS " is the first stage of a two-step process 
to develop an EU Strategy on IS. The overa ll objectives of the po licy proposal are: 
• to substantially reduce the impact of  invasive species on EU biodiversity, 
• to contribute towards the target of halti ng the loss of biodiversity by 2010 and beyond and 
in particular to tackle the adverse effects of  IS in relation to native European biodiversity, 
• to minimise the economic impact felt by different sectors as a result of IS and thus to 
contribute to the Lisbon Strategy, 
• to tackle the negative economic and social effects and costs that IS may engender for 
Europeans and in particular their wellbeing and health. 
It has been demonstrated above that there are ce rtain gaps in the existi ng EU legislation, and 
consequently not all IS-related issues can be tackled efficiently by the current legal frameworks in place. The development of new legislation takes time and considering the results of scientific research that has demonstrated an expone ntially increasing threat by IS, 
the first step focuses on options and measures that could be implemented immediately while 
carrying out the work needed for the second st ep, i.e. developing the EU Strategy on IS. The 
purpose of the Communication "Towards an EU Strategy on invasive species" and the present 
accompanying impact assessment is to describe th e IS problem and the associated costs and to 
EN 19   EN set out the types of response that  could be envisaged as part of  an EU strategy. To the extent 
possible the costs as well as the benefits of the potential res ponses are described mainly in 
qualitative terms. 
4. POLICY OPTIONS  
With a view to taking action to counteract th e negative impact of IS on the economy, society 
and the European environment and biodiversity, th e following options have been identified:  
Option A:  Business as usual : continuation with the ongoing implementation of 
existing instruments. 
Option B: Maximise use of existing approaches : best use of existing legislation, 
development and implementation of voluntar y codes of conduct, development of an 
early warning and information system, mainte nance of the European inventory of IS, 
increasing awareness, exchange of best pr actice, implementation of eradication and 
control measures at national level. 
Option B+: Amend existing legislation:  (e.g. phytosanitary and wildlife trade 
legislation) to widen th e scope to formally take IS issues into account.  
Option C: Comprehensive, dedicated EU legal instrument:  this option includes the 
rapid introduction of new legislation, enta iling a comprehensive approach towards 
tackling IS, coupled with maximal use of the basic tools described in option B. 
The options A, B and C outlined below are cumulative options of increasing intensity and 
effectiveness, while options B+ and C are mutu ally exclusive. Increased intensity requires 
increased resources, and therefore depends on the willingness to invest. The measures 
identified in option B are not stand-al one measures. They should be seen as cumulative 
measures  which are part of the approach seeking to tackle IS problems in an integrated 
manner and maximise the use of exis ting instruments and legislation. It is feasible and 
desirable to implement certain of  these measures immediately , while developing further 
the comprehensive EU Strategy on IS. The s uggested measures include actions for the 
prevention of intentional and unintentional introduction, early warning and information, 
eradication, containment and control of establis hed IS species. Horizontal measures including 
financing mechanisms, research, functioning su rveillance, risk assessment and monitoring 
systems and raising awareness of the public, au thorities and concerne d industry sectors are 
also addressed. These measures would become an  integral part of the future comprehensive 
EU Strategy on IS. 
4.1. Option A: "Business as Usual" 
Under this option the existing legal frameworks  that tackle in a very fragmented and non-
comprehensive way the issues of IS identified in  the problem definition would continue to be 
implemented.  
For organisms harmful to plants or plant products  and for animal and fish diseases European 
states have a comprehensive framework of laws  and procedures that are harmonised with 
international phytosanitary, zoos anitary and trade ru les. Coverage is mainly focused on 
agricultural pests and diseases affecting crops , livestock and farmed fish. The framework 
EN 20   EN provides for biosecurity controls in the form of certification, quarant ine procedures and post-
entry surveillance as necessary, as well as meas ures to control spread. The effectiveness of 
these instruments is facilitated through clearly identifiable host an d pest targets as well as the 
direct economic benefits of regulation. Because these contaminant pests have an economic impact, strict regulations on imports are in pl ace. For example, the Plant Health Directive 
(2000/29/EC) provides lists of pest species that must be banned from being introduced into 
particular Member States. Existi ng legislation in the field of pl ant health is mainly based on 
the European and Mediterranean Plant Prot ection Organization (E PPO) recommendations. 
EPPO maintains lists of invasive alien species that are recommended fo r regulation to its 50 
member countries. There are currently five inva sive alien plants that are recommended for 
regulation. 
Regarding Biological Control Agents, European countries differ in thei r national regulations 
and capacity for assessing the environmental risk s of these agents. EPPO has compiled a list 
of widely used Biological Agents which are consid ered to be environmentally safe. This list is 
currently being updated. Identifica tion of target species  facilitates the cont rol and eradication 
of pests, pathogens and parasi tes of economic significance.  
Council Regulation 708/ 2007 establishes a framework govern ing aquaculture practices in 
relation to alien species to assess and mini mise the possible impact of these and any 
associated non-target species on aquatic habita ts. It establishes a framework to asses and 
minimise possible impacts on species, habita ts and ecosystem functions which may be 
expected to arise from the introduction or tran slocation of aquatic organisms and non-target 
species in aquaculture and from the spreading of these into the wild. Species that may threaten 
wild fauna and flora are marginally cove red by the Wildlife Trade Regulation (Council 
Regulation 338/97), where four  invasive animal species
21 are currently listed and cannot be 
imported into EU territory. However, the spread of these species within the EU's territory is 
not currently regulated. 
With regard to controls on the introduction of alien organisms to the natural environment, the 
Habitats and Birds Directives contain restrict ions on deliberate introductions of alien species 
into the wild. In relation to control and eradication of IS, the Habitats, Birds, and Water Framework Directives may impose some obliga tions through requirements to maintain the 
ecological status of certain sites. 
Species of birds that are not native to the European territory of the Member States are not 
protected by the Birds Directive unless specifi cally mentioned in the Directive's Annexes
22. 
The Canada goose ( Branta canadensis ) and Wild turkey ( Meleagris gallopavo ) have been 
introduced into Europe and are listed as huntable  species under the Birds Directive. However, 
Canada Geese also naturally occur as migrants  in very small numbers and the Wild Turkey 
does not show invasive patterns.  There would not appear to be  similar listings of non-native 
species in the species annexes of the Habitats  Directive. However, there is at present a 
reference to an invasive species, Azolla, as a typical species associated with the natural 
habitats type (Code 3150) "N atural eutrophic lakes with Magnopotamion or Hydrocharition - 
type vegetation". 
                                                 
21 Species listed are the red-eared slider (Trachem ys scripta elegans); the American bullfrog (Rana 
catesbeiana); the painted turtle (Chrysemys picta); and the American ruddy duck (Oxyura jamaicensis). 
22 A listing of non-native bird species is available on the web site of the Commission at 
http://ec.europa.eu/environment/n ature/conservation/wildbirds/eu _species/introd_species_en.htm 
EN 21   EN However, as demonstrated above this option does not provide for a comprehensive way to 
deal with all aspects of IS (see also in 2.3 the identified reasons for taking action at EU level). 
In the wake of the expected dramatic increase of IS it can be expected that the costs in relation 
to damage caused by IS will increase  accordingly under this scenario.  
Although this option implies some measures to prevent the introduction of  certain IS, it will 
not be sufficient to counteract the increasing th reat. With regard to early warning and rapid 
eradication, the BAU option is not functional.  Sporadic eradication measures in some 
countries cannot solve the problem.  The situation is the same in  relation to control and long-
term containment. 
4.2. Option B: "Maximise the use of existing approaches"  
This option involves making the be st use of existing EU legislat ion, combined with voluntary 
codes of conduct, the establishment of an early  warning and information system, maintenance 
of the European Invasive Species inventory, aw areness-raising activities, exchange of best 
practice, and eradication and cont rol measures at national level. 
The measures under this option should be implem ented immediately while developing the EU 
Strategy on IS, which will be subject to follow-up of the present Communication. 
In the following section the measures are grou ped according to the "three-stage hierarchical 
approach"23: 1) prevention, 2) early detection and eradication, 3) control and long-term 
containment. This approach addresses new introductions (via prevention) as well as established species (v ia steps 2 and 3). 
4.2.1.  Prevention 
Prevention is seen as the most cost-efficient wa y to tackle the risks posed by IS. This involves 
giving priority to measures take n to prevent such species being introduced into EU  territory in 
the first place or spreading to new areas within  EU territory. To identify relevant species for 
attention, to channel resources effectively and to  assess and mitigate their risks, risk analysis 
procedures are necessary to justify which sp ecies should be prohibite d or controlled. The 
existing system for Pest Risk Analysis used fo r assessing and mitigating plant pest risks can 
be used as an example. Work is in hand with in the EU to develop more generic assessment 
tools. 
                                                
 
23 The three-stage hierarchical approach entails: 
 1) Prevention – Prevention is generally far more cost-effective and environmentally desirable than 
measures taken following introduction and establishment of IS. Priority should be given to preventing 
the introduction of IS into th e EU and spread between MS. 
 2) Early detection and rapid eradication – If an IS has been introduced, early detection and rapid 
eradication is the most cost-effective way of preventing its establishment and wider spread. 
 3) Long-term control and containment – If eradication is not feasible, IS population should be 
controlled in order to prevent further spread. Control measures should be implemented. 
EN 22   EN Best use of existing legislation   
As identified in the problem definition several Community legislative instruments in place 
provide a basis for addressing as pects of IS prevention. However,  gaps remain in particular 
with regard to the regulation of trade in order to avoid ne w introductions of IS. There are 
obstacles to the use of the Wildlife Trade Regulation as well as the veterinary and 
phytosanitary legislation. Neither  of them is optimal to fully tackle the IS issues. 
Nevertheless, the most efficient interim approach  may be to identify those IS with the worst 
impact and seek to have them covered by th e instrument that can best accommodate them. 
This may mean that some highly invasive spec ies in trade known as worst invaders could be 
listed as "ecological threat species" under the Wild life Trade Regulation while invasive 
animal and plant species that can be considered as pests of plants could be covered by the phytosanitary legislation.  
Voluntary codes of conduct
 
Voluntary codes of conduct or good practic es agreed and implemented by concerned 
industries including horticul ture and the pet and ornamental fi sh trade can be a very efficient 
tool to prevent the introduction of IS. Cooperation with concerne d industries is essential. A 
Code of conduct on horticultur e and invasive alien plants24 is currently being developed under 
the Bern Convention on the Conservation of European Wildlife and Natural Habitats and 
EPPO. A few Member States  are developing species- or secto r-specific codes of conduct, e.g. 
the German and Austrian botanic gardens have  recently drawn up a voluntary code of conduct 
for the cultivation and trade of IS25. 
4.2.2.  Early warning and information 
Currently, early detection occurs on an ad hoc ba sis in most MS and the possibility of a more 
systematic approach should be considered. Early warning and prev ention of the harmful 
impact of invasive alien species on ecosystems is a fundamental requirement of the European 
Biodiversity Strategy and the EU Action Plan to 2010 and Beyond (European Commission, 
2006) yet, in the absence of reliable regional an alyses, the European states have been unable 
to tackle this issue strategically (Miller et al. 2006; Hulme et al. 2007).  
Early detection and eradication imply an early  warning and information system based on an 
up-to-date inventory of all alien species known to inhabit Europe. DAISIE, a pan-European 
inventory of alien species26, a three-year (February 2005-Ma rch 2008) research project 
supported by the Sixth RTD Framework Pr ogramme with €2.4 million in funding, has 
delivered a pan-European inventory of invasive  alien species mobilising existing expertise for 
species records. This inventory also includes  and describes alien sp ecies that have a high 
likelihood of introduction or spontaneous spre ad from neighbouring countries, identifies 
priority species and provides a platform for European reporti ng on biodiversity indicators, and 
highlights areas where Europe will need to di rect resources to mana ge biological invasions. 
                                                 
24 Available at http://www.cbd.int/doc/?mtg=sbstta-13 (go to “others”) 
25 Kiehn M, Lauerer M, Lobin W & Schepker H (2008): Grundsätze im Umgang mit invasiven und 
potenziell invasiven Pflanzenarten in Botanischen Gärten. Unpubl. Report, 3 pp. 
26 See http://www.europe-aliens.org/index.jsp 
EN 23   EN It is hoped that the DAISIE database will enco urage the exchange of data among different 
geographical regions and there by serve as a node in the Global Information System for 
Invasive Species. Documenting current inva sions, predicting new invasion sites, and 
preventing invasions are vital to the protection of biological dive rsity in Europe. Prediction of, 
and rapid response to, invasive species requires ready access to  invasive species knowledge 
bases in many countries. It follows that inte rnet-accessible knowledge bases are a valuable 
tool which can provide crucial informati on for the early detection, eradication, and 
containment of invasive species—which is most feasible for species that have just arrived. 
With direct access to national knowledge ba ses throughout Europe, managers and policy-
makers addressing the invasive species challe nge should easily obtain data on which species 
are invasive or potentially invasive in particul ar habitats, and use this information in their 
planning efforts. Agencies respons ible for pest control can quic kly determine if a species of 
interest has been invasive elsewhere in Europe . Importers of new alien species (e.g. nurseries, 
botanical gardens, pet trade) can access data to make responsible business choices. Land 
managers can learn about control methods that ha ve been useful in other areas, reducing the 
need to commit resources for experimentatio n and increasing the speed at which control 
efforts can begin. The information available in the database also presents an outstanding 
resource to synthesise current  knowledge and trends in relation to biol ogical invasions in 
Europe. The data will help identify the scale and spatial pattern of invasi ve species in Europe, 
shedding light on the environmental, social, eco nomic and other factors involved in invasions, 
and can be used as a framework for consider ing indicators for early warning purposes.  
The future of the inventory may increasingly see a move away from a single database to the 
integration of national databases across the sa me infrastructure. In addition to regular 
scientific update, it is also important that the inventory be institutionally recognised as the 
basis of a possible future Early Warning and In formation System for IS. It is suggested to 
have it permanently hosted by the EEA, whic h would be provided with the appropriate 
resources to keep it up and running. A feas ibility study for an IS early warning and 
information system is currently commissioned by the EEA. The amount necessary to keep the 
inventory up to date as the basis for an Ea rly Warning and Information System has been 
estimated at about €500 000 annually, while the amount invested for its initial development 
was €2.4 million. Meanwhile Aquatic Invasions (AI),  an electronic open-access journal 
focusing on biological invasions in European inland and coastal wate rs and potential donor 
areas of aquatic invasive species for Europe27, is also serving several online databases on 
invasive species, including the DAISIE in formation system described above, through 
publication of national checklists of aquatic al ien species, which represent a core component 
of this project database (Gollasch a nd Nehring 2006, Alexandrov et al. 2007, Galil 2007, 
Kerckhof et al. 2007, Minchin 2007). The timely public ation of verified ch ecklists and new IS 
findings may help to keep the DAISIE informa tion system up to date. Figure 6 (in Annex) 
demonstrates the role of AI in a European Early Warning System. Aquatic Invasions 
facilitates the flow of essential information needed for the decision-making processes. Work 
is underway to develop an online risk assessmen t toolkit with early warning functions, which 
may serve as an interactive tr ansmitter of primary informati on on IS from data providers 
upwards to the level of decision-making. Aquatic Invasions will play an important role as an 
essential component of this ne w electronic information framew ork for invasive alien species 
(Panov et al.2008). The online journal BIORISK28 could fulfil the same function for terrestrial 
IS. 
                                                 
27 See http://www.aquaticinvasions.ru/ 
28 See http://www.pensoft.n et/Brochure-BIORISK.pdf 
EN 24   EN The North European and Baltic Network on Invasive Alien Species (NOBANIS)29 has 
developed a network of common databases on a lien and invasive species of the region. The 
geographic scope of NOBANIS ha s recently increased and now also covers Central Europe. 
The common portal facilitates ac cess to IS-related da ta, information and knowledge in the 
region and its website hosts detaile d fact sheets of the worst inva sive species. Information is 
kept up to date via a netw ork of national contact poin ts. NOBANIS is thus a vital 
complementary IS information hub to DAISIE.  
A system for early warning and er adication should also contain methods and expertise for risk 
assessment of invasive species so  as to rapidly evaluate risks and identify what measures are 
necessary to manage the risks, tools for shari ng information with partners within the system, 
monitoring schemes to identify new invasive speci es and alien species already present in the 
area that have begun to exhibit invasive characteristics, and response plans to enable and 
ensure a rapid response and eradication where necessary. 
Criteria-based risk assessment of IS is one of the key principles in implementing the 
precautionary approach in IS management (G enovesi & Shine 2003). Hence, several national 
risk assessment methodologies and blacklists of IS have been recently developed in Europe: 
e.g. Switzerland30, Belgium31, UK32 and Germany and Austria33. These methodologies and the 
experience gained in their national implem entation deliver important information for 
developing a European risk assessment system. 
Early warning and information systems already exist in the Plant Health framework. 
EUROPHYT allows the notifica tion of interceptions of pe sts between countries. EPPO 
publishes a monthly Reporting Se rvice on invasive alien species freely available at 
http://www.eppo.org/PUBLICATIONS/r eporting/reporting_service.htm .  
4.2.3.  Eradication and control measures  
Detected IS should be eradicat ed within a limited period of time before the population is 
established, i.e. as soon as  possible. Early action has been proven to be much more 
economically and environmentally effective. Rapi d intervention should be preferred to a long 
approval process for plans, so that eradication remains feasible. Ensuring public understanding is crucial to a voiding public protests reflecti ng, for instance, concerns of 
animal right groups. At the moment eradicatio n programmes for invasive alien species that 
threaten the ecological status of Natura 2000 sites can be sup ported under LIFE+. Currently 
there are a number of projects that include ac tions for eradicating IS, for example €1 827 130 
will be provided to Spain and the UK for eradication of the ruddy duck Oxyura jamaicensis , 
                                                
 
29 participating countries in NOBANI S: Austria, Belgium, Denmark, Estonia, Finland, Faroe Islands, 
Germany, Greenland, Iceland, Ireland, Latvia, L ithuania, The Netherlands, Norway, Poland, European 
part of Russia, Slowakia, Sweden . http://www.nobanis .org/default.asp 
30 Weber, E., Köhler, B., Gelpke, G., Perrenoud, A. & Gigon, A. (2005): Schlüssel zur Einteilung von 
Neophyten in der Schweiz in die Schwarze List e oder die Watch-Liste. Bot. Helv. 115: 169-194. 
31 Branquart, E. (2007): Guidelines  for environmental impact assessm ent and list classification of non-
native organisms in Belgium, Version 2.5. http://www.IS.biodiversity.be 
32 Copp, G.H., Garthwaite, R. & Gozlan, R.E. (2005):  Risk identification and asseement of non-native 
freshwater fishes: concepts and perspectives for the UK. CEFAS, science series technical report 129, 32 
pp. 
33 Essl F, Klingenstein F, Nehring S, Otto C, Rab itsch W & Stöhr O (2008): Schwarze Listen invasiver 
Arten – ein wichtiges Instrument für den Naturschutz! Natur und Landschaft, in press. 
EN 25   EN through a programme running from 2005 to 2010. Th e Council of Europe has recommended 
that its countries eradicate specific invasive alien plants . EPPO has long experience of 
providing recommendations for eradication and containment of specie s (e.g. about to be 
published, recommendation on Ambrosia artemisiifolia , Heracleum mantegazzianum, Sicyos 
angulatus , etc.). Public-private partnerships will  be encouraged, which ought to be mutual 
beneficial and prevent or at least lower ecological, ec onomic and social damage. 
4.3. Suboption B+: Adapting existing legislation 
This option involves amending existing legislati on to widen the scope to formally take IS 
issues into account. This include s adjustment of existing legisl ation on plant/animal health to 
cover a broader range of poten tially invasive organisms a nd expansion of the list of 
“ecological threat“ species for which import and internal movement are prohibited under the 
Wildlife Trade Regulation to prevent trade in a larger number of IS. Additional resources 
would need to be dedicated to IS in the asse ssment process and in the border control activities 
performed by Member States. Member States should receive clarification on the scope of 
national IS measures consis tent with the EC Treaty. 
With regard to preventing the introduction of certain IS, this option would strengthen option 
B, as the legal framework would prohibit intent ional introduction. However, it is unlikely to 
be sufficient to counteract the increasing threat, as none of the current legisla tion is really 
tailored to dealing with IS. With regard to  early warning this op tion could be a major 
breakthrough, but eradication measures rema in subject to the goodwill of the countries 
concerned; this option will bring some improvement, but it will not solve the problem. The situation is the same in relation to  control and long-term containment. 
Option B+ and option C are mutually exclusive.
 
4.4. Option C: Comprehensive, dedi cated EU legal instrument  
Building on the measures outlined  under option 2 an EU Strategy on IS could be developed to 
combat the threat posed by biological inva sions, through coordinated action taking into 
account international policy instruments, guidi ng principles and procedures addressing 
invasive species strategies relevant to Eur ope. The EU Strategy on IS shall be subject to 
follow-up to the Communication addressed in this  impact assessment. Therefore the following 
outline only gives a brief overview on the visi on, objectives and underlying principles of a 
future comprehensive EU strategy on IS. 
Box 3: EU Strategy on IS 
Vision : Europe where biodiversity, native species, in cl. the genetic variations, and ecosystem 
services are not declining or being lost due to IS. 
Global objective:  To substantially reduce the impact of  invasive species on EU biodiversity, 
to contribute to halting biodiversity loss by 2010 and beyond, to minimise economic and 
social costs caused by IS and thus contribute to the Lisbon Strategy. 
EN 26   EN Specific objectives:  
(1) Measures to address intentional and uni ntentional introduction are in place. 
(2) Measures to address "escapees" and establis hed IS species are in place (eradication, 
containment, control). 
(3) A well-functioning early warning and inform ation system is in place supported by 
functioning surveillance a nd monitoring systems. 
(4) Financing mechanisms to eradi cate/control IS are in place. 
(5) MS implement national strategies  and cooperate at EU level. 
(6) The public understands and accepts necessa ry measures and contributes to the 
objective. 
Source: IS discussion paper 
In discussions with representatives of the Memb er States and other stak eholders, some general 
principles for the development of a strategy have been identified as  building blocks. These 
are: 
– Precautionary principle 
– Subsidiarity principle 
– Cooperation 
– Solidarity principle 
– Public involvement 
In addition, the strategy should in corporate the relevant existing international principles and 
strategies like the CBD Guiding Principles as  well as the European Strategy on IAS (adopted 
by the Bern Convention under the Council of Eur ope). The strategy should make use of the 
best examples from various other institutions and initiatives and EU Member States' national IS strategies where available. 
4.5. Horizontal issues 
The following horizontal issues are relevant for all options. 
Communication, education and public awareness
 
It is essential to have an informed and e ngaged public in order to address the IS issue 
successfully. Administrative / legal instruments alone cannot cover all as pects of IS. The aim 
of communication, education and awareness-raisi ng activities should be to build a sense of 
responsibility amongst European citizens with regard  to import, export and unintentional 
introduction of potential IS to and from thir d countries and their movement in the intra-
Community trade zone, and also in relation to detection/reporting, erad ication and/or control 
EN 27   EN programmes where public support can be crucial to achieving a successful outcome. A better 
informed public would probably bring fewer inva sive species into thei r gardens and ponds.  
An important segment of these activities would be directed towards policy makers as well as 
to sectors engaged in activities  that lead to uninte ntional introduction. Thes e include the retail 
sector where emphasis should be put on preven ting potential escapes of species. Voluntary 
instruments could be used  to involve retailers. 
The other major objective of public awareness would be to fo ster acceptance by  the public of 
the need for measures to address IS. The public  is more sensitive to eradication of some 
species, especially mammals and birds e.g. grey squirrels, and consequently more 
communication would be needed here.  
Communication and awareness-ra ising activities should addre ss all relevant levels: EU, 
national, regional and local. 
Exchange best practice and suppor t action at Member State level  
Coordination should be improved and strong partnerships built. Action to address the IS issue 
should be strengthened at Member  State level. There is a strong need for development and 
implementation of national strategies on IS, as is already being done in a number of Member 
States. Due to the different economic sectors an d groups that are affected by the very nature 
of IS, Member States should be encouraged to  include all involved se ctors and to develop 
wide consultation processes. It is important to link national and regional strategi es. There is a 
need to provide and disseminate to the Member States relevant information available. Existing web-based instruments could be used  for this purpose, like the EC CHM
34 hosted in the EEA. 
Knowledge base  
Serious challenges posed by massive human-mediate d introductions of i nvasive species have 
resulted in the strengthening of  international cooperation in re search, information exchange 
and management of aquatic invasions within th e framework of different international group 
activities related to aquatic invasi ons in Europe and adjacent areas. 
However,  further development and expansion of rese arch to include terrestrial organisms 
should be supported in a stream lined way that builds on existing European frameworks. It 
would be important to analyse research gaps and needs and to  ensure that there is a good 
balance between research on asse ssing the risks and extent or severity of the problem, e.g. 
prediction of invasion for new species, and resear ch into developing cost-effective control and 
management methods, e.g. bio-control. Research  into better predicti on of invasions should 
address: increasing knowledge ab out vectors, the inherent fact ors that may prevent IS and 
those that facilitate them. There is also still a lot to learn about the magnitude and pathways of 
invasive species, how they impact on ecosystems, and how climate change will affect biological invasions. The integrated approach  initiated in the ALARM project should be 
pursued further. 
                                                
 
34 EC Clearing House Mechanism, http://biodiversity-chm.eea.europa.eu/ 
EN 28   EN Monitoring and reporting, and th e development of appropriate indicators, should also be 
supported in order to obtain fee dback on policy effectiveness. D uplication with other existing 
monitoring and reporting requirements should be a voided so as not to squander resources, and 
synergies should therefore be explored with si milar work taking place in the field of nature 
and biodiversity, but also in the various sectors identified (i.e. ag riculture, forestry, fisheries). 
The results of research and monitoring should f eed into information systems and should also 
support the exchange of information on good and bad practices. 
Financing  
Adequate financing for dealing with IS should  be ensured and sought. Over the last 15 years 
the EC has helped to finance almost 300 projects  addressing invasive al ien species, for a total 
budget exceeding €132 million. This was shown in an analysis of the LIFE Programme and 
the Framework Programmes for Research and Technological Development (RTD), being the 
two major EU funding sources for management actions and research on IS (Scalera R. 2008). 
Currently it is mainly the LIFE+ programme that supports action on IS through specific 
projects. However, outside this  specific nature conservation project-oriented regime and 
project-based financing, other sources are needed  to support a number of further actions and 
to develop more flexible mechanisms, particul arly given the far-reaching impact generated by 
IS across all sectors and the critical importanc e of rapid response to maximise chances of 
eradication. 
If new measures are required from Member St ates, the issue of financing will be important. 
The option of dedicated EU funding for IS, similar to the solidar ity fund under plant 
protection policy, will be examined in gr eater detail during the follow-up to this 
Communication. An assessment of the exact financia l needs of the Member States with regard 
to the financing of appropriate measures to prev ent, eradicate and contro l IS in their territory 
will be carried out. Possibilities of using ot her EU funding mechanisms could be sought post-
2013. Apart from the analysis of the financial needs, a scoping analysis is planned with a view 
to identifying how the various EU F unds can contribute financially to 
awareness/communication, control and eradication activities. In  addition, opportunities should 
be explored for involving the private sector through the use of insu rance and other economic 
and financial instruments. Guaranteeing suffici ent resources and establishing financial self-
sufficiency is important for long-term control and containment measures. Efforts to maximise 
the available resources and their sustainability  can be sought by promoting full participation 
of local communities and key stakeholders in project development, management and 
implementation to ensure a long-term local commitment. 
EN 29   EN 5. COMPARING THE OPTIONS  
The dramatic increase in IS linked to extende d trade activities and hum an mobility leads to 
environmental and economic damage and will ge t even worse in the future. Option 1 would 
be likely to lead to hasty and costly "end of pipe" reactions in the future, which may well go 
beyond the costs generated by options 2 and 3. Table 4 below compares the options: 
Table 4: Comparison of the four options examined 
 A) Business as Usual B) Maximising 
existing approaches B+ Amending existing 
legislation C) Comprehensive EU 
Strategy  
Level of intensity with regard to 
resources 
needed No additional 
resources are to be used. The suggested 
measures require an additional (medium) 
input in the form of 
more resources, for 
e.g. proper 
maintenance of the IS inventory, which is 
the basis for an early 
warning and information system 
that would need about 
€500
 000 annually. The suggested measures 
require a medium to high input to amend the 
existing relevant 
legislation. The development and 
implementation of an EU Strategy on IS needs 
commitment of significant 
resources. The analysis of 
necessary resources is 
subject to the second step. 
Likely economic effects-impact Expected increase of 
IS will lead to further increases in economic 
losses (estimated 
current costs in Europe: 12.7 
billion/year- note that 
this amount is likely to be an 
underestimate, as it is 
based on available 
information on 
documented costs, which does not cover 
all IS impacts), while 
the same will happen outside the EU. Expected increase of 
IS will lead to further increases in economic 
losses, while the same 
will be experienced outside the EU. Some 
marginal decrease in 
the impact may occur due to increased 
awareness of IS and 
action at local and 
national level. 
However, this decrease is likely to be 
counterbalanced by 
the overall increase in IS. As option B, with a 
slight decrease of IS introduction and 
consequent decrease of 
economic effects-impact once the 
relevant legislation will 
have been amended and implemented. However, 
the effectiveness will be 
hampered, because 
patchiness and legal 
uncertainties will remain. Implementation of an EU 
Strategy on IS will help to slow down the rate of 
increase of the problem in 
particular by decreasing the occurrence of new 
introductions, thus 
significantly reducing economic losses. 
EN 30   EN  A) Business as Usual B) Maximising 
existing approaches B+ Amending existing 
legislation C) Comprehensive EU 
Strategy  
Likely environmental effects-impact The expected increase 
of IS will lead to further pressure on 
biodiversity and 
hamper the efforts to halt biodiversity loss. 
It will lower the 
resilience of ecosystems and their 
capacity to adapt to 
climate change, the 
same will happen 
outside the EU. The increased 
awareness and application of 
voluntary codes of 
conducts and the implementation of 
national IS strategies 
where available, may lead to local success, 
however in absence of 
a co-ordinated 
approach the gaps in 
tackling the issue of IS will remain. As option B, with a 
slight decrease of IS introduction and 
consequent decrease of 
environmental effects-impact once the 
relevant legislation will 
have been amended and implemented. However, 
the effectiveness will be 
hampered, because 
patchiness and legal 
uncertainties will remain.  The implementation of an 
EU Strategy on IS will help to alleviate the 
problem in particular by 
decreasing the threat of new introductions. Co-
ordinated eradication and 
control measures will stabilise and eventually 
improve the situation and 
contribute to halting 
biodiversity loss. 
Likely social effect - impact The expected increase 
of IS will have 
increased negative health implications, 
which will in turn 
heighten public awareness, increasing 
public pressure for 
action, the same as is happening already in 
places outside the EU 
e.g. New Zealand, Australia, USA… The expected increase 
of IS will lead to 
aggravation of negative health 
effects, which will in 
turn heighten public awareness, increasing 
public pressure for 
action, and the same is expected to happen 
outside the EU. 
Communication actions will encourage 
responsible behaviour 
by the public and the sectors involved in 
trading IS (pet trade, 
horticulture, energy 
...) As option B, with a 
slight decrease of IS 
introduction and consequent decrease of 
social effects-impact 
once the relevant legislation will have 
been amended and 
implemented. However, the effectiveness will be 
hampered, because 
patchiness and legal uncertainties will 
remain. The implementation of an 
EU Strategy on IS will 
significantly alleviate the problem and increase 
awareness of the public 
and the sectors concerned, and stimulate more 
responsible behaviour. 
Uncertainty to 
reach the policy 
objectives It is certain that with 
the BAU option only, the EU will fail to 
successfully deal with 
the threat and subsequent impact of 
IS. The suggested 
measures are elements towards dealing with 
IS in a more 
comprehensive and strategic manner. 
However, as stand-
alone measures they are deemed 
insufficient to reach 
the European policy objectives set. The amending of 
existing legislation will bring some 
improvement, but it 
does not provide for comprehensive and 
strategic instruments 
necessary to cope successfully with IS. The implementation of an 
EU Strategy on IS would be more likely to reach the 
European policy objectives 
set. 
EN 31   EN  A) Business as Usual B) Maximising 
existing approaches B+ Amending existing 
legislation C) Comprehensive EU 
Strategy  
Development of impact over time The currently existing 
problems will continue to increase 
and accelerate and 
will most likely be aggravated by the 
impact of climate 
change. The already existing 
problems will continue to increase, 
maybe at a slightly 
lower level, and will most likely be 
aggravated by the 
impact of climate change. As option B The implementation of an 
EU Strategy on IS will help to stabilise and 
eventually improve the 
situation.  
Affected 
groups All groups of society 
and certain economic 
sectors (e.g. 
agriculture, forestry, 
fishery, tourism, health, energy) All groups of society 
and certain economic 
sectors (e.g. 
agriculture, forestry, 
fishery, tourism, health, energy) All groups of society, in 
particular sectors 
involved in trade with 
IS including pet trade, 
horticulture, energy, etc. All groups of society, in 
particular sectors involved 
in trade with IS including 
pet trade, horticulture, 
energy, etc. 
Obstacles to compliance n/a Institutional inertia 
due to the overloaded agendas and 
insufficient 
commitment of resources prevent the 
maximisation and 
prioritisation of existing resources 
including the 
establishment of an Early Warning and 
Information System 
including the 
maintenance of the IS 
inventory  Amending existing 
legislation is a tedious undertaking, where 
effort and benefit have 
to be properly balanced. The willingness and 
preparedness of the 
parties involved are limited, as the measure 
is largely perceived as 
an additional burden beyond their remit. Insufficient commitment 
and deployment of resources prevent the 
development and 
implementation of a comprehensive EU 
Strategy on IS. 
The following table outlines a ra nge of generic IS policy options  and measures, their scope of 
application, and some of the cost s they may entail. These measures  will be further analysed in 
the second phase of this work, with a view to identifying those measures that will be part of 
the EU Strategy on IS.  
EN 32   EN Table 5: Generic IS policy measures and actions, scope and indicative types of costs 
Type of measures / actions Scope of 
application Possible types of costs associated 
with the measures /actions Possible actors  
Prevention 
Pre-import controls (process and 
product standards that exporters must 
meet in order to gain access to markets).  
 Country of export. 
 Offshore inspection and quarantine 
(personnel, equipment, procedures such 
as fumigation, certification). Pathway 
controls e.g. offshore ballast water 
exchange pre-entry. Border controls, 
Custom services 
Specific controls to mitigate IS 
threats to the natural environment 
should be coordinated with import 
regulations and procedures to ensure plant, animal and food health Borders  Customs services; maintenance of entry 
points; border inspections; quarantine 
procedures and equipment (X-rays, 
laboratories, sniffer dogs, fumigation); 
post-entry quarantine where necessary. 
Import risk analysis procedures.  
Listing of species/commodities that are 
authorised /restricted. 
Training and capacity-building Border controls, 
Custom services 
Controls on intentional introductions. Point of import or in-
country. Risk assessment procedures. 
Listing of authorised/restricted species.  
Permit/licensing systems.  
Measures to minimise escape risk (e.g. 
from contained facilities). 
Follow-up monitoring and reporting. 
Compliance (including voluntary). Competent 
Authorities 
Research Institutions 
Border controls, 
Custom services  
Pathway management measures 
(commodities, transportation, sectoral 
activities etc.). 
 
 Variable.  Pathway/vector risk assessment to 
assess means of entry/dispersal of IAS 
that could affect biodiversity. 
Technical measures to address 
identified risks. Follow-up monitoring. 
Deterrents/incentives to support best 
practices Competent 
Authorities 
Research Institutions Border controls, 
Custom services, 
Civil Society
 
EN 33   EN Type of measures / actions Scope of 
application Possible types of costs associated 
with the measures /actions Possible actors  
Regulatory/voluntary controls on in-
country movement, trade, other uses 
(aim is prevention of spread: measures support long-term 
containment) 
 Countrywide or 
targeted at specific 
areas (non-invaded 
areas; vulnerable 
ecosystems like 
wetlands; protected 
areas; islands etc.)  Permit/licensing systems e.g. for retail 
and other containm ent facilities.  
Legal prohibitions (e.g. on release). 
Monitoring and reporting. Compliance 
and enforcement. 
Physical barriers and deterrents for IAS 
exclusion (from crops , protected areas, 
gardens, lakes) or containment (in 
already invaded areas).  
Modification to physi cal infrastructure 
e.g. alteration to dams. Competent 
Authorities 
Research Institutions Retailers 
Construction sector 
Targeted communication campaigns 
and conflict reduction measures Countrywide or 
issue-specific Information materials, media 
campaigns, participat ory consultations 
for controversial species/issues.  Civil Society 
Government 
Early detection and rapid response  
Monitoring and early warning 
systems.  Around major entry 
points/disturbed areas 
where easier for IAS 
to establish/protected 
areas/ vulnerable 
ecosystems.  Monitoring protocols. 
Personnel and equipment. Coordination 
of volunteer contributors. 
Well-structured reporting systems. Government 
Research Institutions  Civil Society 
Information exchange  European, national, 
transboundary, regional, global. Operational coordination. 
Data protocols. Electronic 
infrastructure. 
 Government 
Research Institutions  
Civil Society 
Industry (e.g. pets, 
ornamental)  
Rapid response procedures. Where needed 
(aquatic as well as 
terrestrial 
ecosystems). Authority under relevant legislation 
(private as well as public property). 
Capacity (trained teams). Contingency 
planning and equipment. 
Funding for rapid response. Government 
Research Institutions  
Civil Society 
Industry (e.g. pets, 
ornamental) 
EN 34   EN Type of measures / actions Scope of 
application Possible types of costs associated 
with the measures /actions Possible actors  
Long-term control and containment  
General measures for eradication, 
control or containment. National. New/revised le gislation as necessary 
Strategic planning. 
Management plans based on ecosystem 
approach or for individual IAS. 
Research, supported by risk and 
environmental impact assessment for 
control techniques. 
Public consultation procedures. 
Transboundary consultation where 
necessary; Personnel, equipment, 
training. 
By-laws (local regulations). 
Monitoring of results. 
Compliance (including voluntary). Government 
Research Institutions  
Civil Society 
Industry (e.g. pets, 
ornamental) 
Mechanical (plants) Where needed. e.g. thinni ng/removal of trees and 
shrubs; grazing and mowing regimes; 
mechanical rem oval of algae. idem 
Mechanical (animals) Where needed. e.g. shooting, trapping, snares; drainage 
of ponds; cleaning of catchment 
installations and clogged gear; de-
fouling of fishing gear and boats. idem 
Chemical Where needed. Herbicides and pesticides (constraints 
include resistance of target species, Ban 
on use of certain chemicals, lack of 
target specificity, contamination). 
Poison (e.g. bait): risk assessment to 
avoid impact on non-target species. 
Contraceptive techniques. idem 
Biological control 
 Where needed. Research to ensure introduced agent is 
host-specific. 
Appropriate legislation. 
Notification/consultation directed to 
other potentially a ffected countries. 
Monitoring. idem 
Restoration Where needed. Replanting, structural repair, ongoing 
maintenance. Incentive measures. idem 
EN 35   EN Type of measures / actions Scope of 
application Possible types of costs associated 
with the measures /actions Possible actors  
Legal and institutional framework  
Strengthened IAS policies and legal 
framework. European, 
National, local. Review of exis ting measures. 
Development of coordinated national 
strategy/action plan. Development or 
amendment of legislation and 
regulations. 
Development of voluntary protocols, 
incentives, financing and cost-recovery 
mechanisms. Government 
Civil Society 
Industry (e.g. pets, 
ornamental) 
Creation of/mandate for a high-level mechanism to coordinate IAS policy 
and planning, including in the natural 
environment.  European, 
National. Operating costs of national coordination 
mechanism and/or technical advisory 
committees.  Government 
European IAS database (stand-alone 
or integrated into other biodiversity 
information mechanisms)  European and 
National (scope to 
pool resources with 
neighbouring countries). Researcher time and equipment to 
establish baseline information. 
Technical infrastructure (links to 
national and international clearing-
house mechanisms). Maintenance and 
regular updating of database and broad 
links. 
Public access. Government 
Research Institutions 
Civil Society 
Training and capacity-building. Na tional, local. Awareness-building at 
governmental and technical level. 
Taxonomy cost of diagnosis. All 
areas of operation, as needed. Government 
Research Institutions  Universities, 
Secondary schools 
Civil Society  
6. CONCLUSIONS  
Scientific research and experience with projects targeting the cont rol or eradicati on of IS have 
demonstrated the magnitude of the IS probl ems for various economic sectors and made it 
clear that the problem will exponentially increas e unless appropriate action is taken urgently. 
A coordinated approach at EU  level is indispensable, as  the impacts are transboundary. 
Therefore the development of an  EU Strategy on tackling IS is the most appropriate way to 
address the problem and meet the policy objectives set.  
It has been demonstrated that developing this strategy will take some time, to allow actions 
and the legislative framework to be stud ied in detail and appropriately prepared. 
Subsequently, the measures outlined under option B need to be taken up  as soon as possible 
and with immediate effect. Thes e include the estab lishment of an EU Early Warning and 
Information System and the maintenance of the European inventory of alien species that has 
EN 36   EN been delivered by the DAISIE project. These tw o distinct actions, together with improved 
communication, raising awareness of the public and the economic sectors affected, education 
and establishment of voluntary codes of conduct will make fo r greater EU efficiency in 
dealing with IS problems. 
The collected literature and reports on costs indi cate that the eradicati on, control or long-term 
containment measures that need to be implemented when and where prevention efforts fail or are not implemented in the first place coul d be extremely costly. There are also many 
documented examples of the serious technica l constraints involved in finding successful 
control techniques for i ndividual IS, thus further research and experimentation is needed on 
these aspects.  
The internationally-accepted position implies th at prevention is better than cure when it 
comes to IS and should be prioritised in policy development (see the CBD Guiding Principles). Prevention is likely to be the most  cost-effective option, given the sheer scale of 
negative economic, social and environmental eff ects of IS. Therefore i nvestment in robust and 
coordinated prevention and early warning and in formation systems to minimise any negative 
impact on biodiversity can deliver positive results for multiple sectors and interests, including: 
• more effective conservation of thre atened species and their habitats; 
• more systematic management of IS threat s to vulnerable ecosystems such as wetlands; 
• reinforced protection of biodi versity hotspots, including Na tura 2000 sites and islands in 
EU overseas entities; 
• maintenance or restoration of ecosystem function and services; 
• maintenance or recovery of yields a nd quality of biological production systems 
(agriculture, fisheries, forestry); 
• avoidance of trade-related problems (e.g. lo ss of markets due to infested goods);  
• reduced constraints on water s upply, transportation, en ergy production, fl ood and fire risk 
management; 
• preservation or restoration of landsca pe, recreational and tourism amenity;  
• reduced health expenditure for allerg y management and disease control.  
It is recognised that individua l options have associated cost s and economic implications for 
different categories of stakeholders. The aim should be to select and combine those policy 
options and within these the measures that efficiently minimise IS risk, keep the costs of supply for a service/activity low, minimise the cost of compliance and administration and 
ensure fairness between different categories of stakeholders. A common and cooperative 
approach to the problem of invasive species is essential if  we are to find cost-efficient and 
effective ways to prevent the introduction of invasive species and es tablish eradication or 
control programmes.
 
EN 37   EN 7. MONITORING AND EVALUATION  
The core indicator of progress towards meetin g the objectives would be  the existence of a 
functioning pan-European Early Warning an d Information System (EWIS) on Invasive 
Species based on a regularly upda ted inventory by 2009. EWIS w ould involve cooperation of 
researchers, civil society, concerned industry sectors, government institutions and the EEA.  
The EU Strategy on IS is one of the actions identified in the EU Biodiversity Action Plan 
(BAP). Reporting on progress made with regard to t ackling the threat of IS is an integral part 
of the BAP reporting. 
"Trends in invasive species" is one of the European Headline Indicators for Biodiversity35 to 
assess progress towards the 2010 target of Halting Biodiversity Loss. The key policy questions concern control of the main pathways for invasive species establishing in Europe 
and management actions for invasive species pr ioritising the species that create the largest 
negative impact on biodiversity and are directly relevant for the monitoring and evaluation of 
the measures dealt with in th is impact assessment report. 
                                                
 
35 For more information see SEBI (Streamlining European Biodiversity Indicators) 2010 
http://biodiversity-chm.eea.europa.eu /information/indi cator/F1090245995 
EN 38   EN LIST OF ANNEXES , SUPPORT DOCUMENTS AND REFERENCES  
Annexes  
Annex A: Figures and tables 
Annex B: Description of relevant EU research projects Annex C: Examples of costs and benefits of IS policy measures 
Support documents and key references
 
Bella S., Nehring S., Panov V., Waterways as Invasion Highways – Impact of Climate Change 
and Globalisation , chapter 5 of "Biological Invasions" Ecological Studies Vol. 193, Springer-Verlag 
Berlin Heidelberg 2007. 
Capdevila L. and Ziletti B. A perspective on climate change and invasive species . Discussion paper 
prepared for the Convention on the Conservation a nd European Wildlife and Natural Habitats, March 
2008 
European Commission, DG Environment.  Developing a EU Framework for Invasive Alien Species,  
Discussion Paper by the IS consultatio n group of Member State represen tatives and other stakeholders 
see http://ec.europa.eu/environment/nat ure/invasivealien/index_en.htm  
Genovesi P, Scalera R, Towards a Black List of Invasive Alien Species Entering Europe through 
Trade and Proposed Responses . Document prepared the Convention on the Conservation and 
European Wildlife and Natural Habitats, November 2007. 
Heywood V. and Brunel S., Code of Conduct on horticulture and invasive alien plants , document 
prepared the Convention on the Conservation and Eu ropean Wildlife and Natural Habitats, December 
2007 (second draft) 
Hulme P., Bacher S., Kenis M., Klotz S., Kühn I., Minchin D., Nentwig W., Olenin S., Panov V., 
Pergl J., Pysek P., Roques A., Sol D., Solarz W., Vilà M., Grasping the routes of biological 
invasions: a framework for inte grating pathways into policy , Journal of Applied Ecology, 2008 
Hulme P. Biological Invasions in Europe: Drivers,  Pressures, States, Impacts and Responses.  The 
Royal Society of Chemistry, 2007. 
Hulme P. et al 2008, "A pan European inventory of alien species: rationale, implementation and 
implications or managing biological invasions";  chapter in DAISIE (eds) The Handbook of Alien 
Species in Europe, (in press) Springer, Berlin. 
Kenis M., Auger-Rozenberg M-A., Lopez-Vaamonde C., Timms L., Péré C., Cock M., Settele J. , 
Augustin S., Roques A., Ecological impact of invasive alien insects - a world review (in press). 
Kettunen, M., Genovesi, P., Gollasch, S., Pagad, S., St arfinger, U. ten Brink, P. & Shine, C. 2008. 
Technical support to EU strategy on invasive species (IS) - Assessment of the impacts of IS in 
Europe and the EU (Final module report for the European  Commission). Institute for European 
Environmental Policy (IEEP), Brussels, Belgium. 40 pp. + Annexes., May 2008 (DG ENV contract). 
Miller C., Kettunen M.,  Scope options for EU Action on invasive alien species (IS),  June 2006. At: 
http://ec.europa.eu/environment/nature/inv asivealien/docs/2006_06_IS_scope_options.pdf  
EN 39   EN Olenin S., Analyses of naturalisation rates for different taxa, biomes and Member States , DAISIE 
deliverable 11, February 2007. 
Panov V. et al, "New electronic journal "Aquatic Invasions": an important part of the 
developing European early warning system on aquatic invasive species ", ALARM deliverable D 
5.1.7 Feb 2008. 
Panov V.et al, Interim protocols for risk assessment of  aquatic invasive species introductions via 
European inland waterways , ALARM deliverable D. 4.1.3.10, February 2008-06-04 
Pysek P., Bacher S., Chytry S., Hulme P., Kenis M., Minchin D., Nentwig W., Olenin S., Sol D., 
Solarz W., Vilà M, Predictive models of the susceptibility of representative European ecosystems 
to invasions , ALARM deliverable 1.3.2. March 2006 
Scalera R. EU funding for management and research of invasive alien species in Europe , April 
2008 (EEA contract N-3603/B2007.EEA.53070) . available at http://biodiversity-
chm.eea.europa.eu/information/F1059808330/ report-eu-spending-invasive-species-2008 
Sherley G., Timmins S. and Lowe S. Invasive species in the Pacific:  a regional strategy. South 
Pacific Regional Environment Programme  (SPREP), Approved by SPREP member countries in 
September 2000. 
Shine C., Williams N., Gündling L. A guide to designing legal and institutional frameworks on 
Alien Invasive Species, Environmental Policy and Law Paper No 40, 2000. 
Van der Weijden W., Leewis R., Bol P. Biological Globalisation, Bio-invasions and their impacts 
on nature, the economy and public health , KNNV Publishing 2007. 
Vilá M. and Basnou C. , State of the art review of the environmental and economic risks posed by 
invasive alien species in Europe , DAISIE deliverable 14, February 2008.  
EN 40   EN ANNEX A - Figures and Tables  
Figure 1  demonstrates the main dir ect drivers on biodiversity 
Main Direct Drivers 
The cell color indicates the impact to date of each driver on biodiversity in each biome over  the past 50–100 years. The arrows  
indicate the trend in the impact of the driv er on biodiversity. Horizontal  arrows indicate a continuation of the current level of 
impact; diagonal and vertical arrows indicate progressively incr easing trends in impact. This Figure is based on expert opinion  
consistent with and based on the analysis of drivers of change in  various chapters of the assessment report of the Condition an d 
Trends Working Group. This Figure present s global impacts and trends that may be di fferent from those in specific regions.  
 
Source: Millennium Ecosystem Assessment, 2005. Ecosystems and Human Well-being: 
Biodiversity Synthesis. World Resources Institute, Washington, DC. 
EN 41   EN Figure 2  demonstrates the relative contribution of pathways of introduction shown for 
naturalised aliens to Europe, i.e. species with the area of origin outside Europe. Pathways of intentional introductions are und erlined, unintentional not. Base d on 2024 naturalised aliens, 
data from Lambdon et al. (2008) 
 
Source:  Hulme P. et al 2008, " A pan European inventory of alien species: rationale, 
implementation and implications or  managing biological invasions "; chapter in DAISIE 
(eds) The Handbook of Alien Species in Europe, (in press) Springer, Berlin 
EN 42   EN Figure 3  represents a simplified framework to categorise pathways of initial introduction of 
alien species into a new region. Alien species may, as a direct or in direct result of human 
activity, arrive and enter into a new region through three broad mechanisms: the importation 
of a commodity, the arrival of a transport vector and/or na tural spread from a neighbouring 
region where the species is itself alien. Five pathways are associated with human activity 
either as commodities (release and escape), contaminants of commodities, stowaways on modes of transport and opportunists exploi ting corridors resulting from transport 
infrastructures. The sixth category highlights alie n species that may arrive unaided in a region 
as a result of natural spread (rather than  human transport) following a primary human-
mediated introduction in a neighbouring region. For each pathway a brief description is 
presented with examples. The different regula tory approaches for each pathway are also 
illustrated. While a case is often made regarding differences between intentional vs. unintentional introductio ns, the scheme highlights a gradient of human intention that reflects 
the difficulty in distinguishing betw een ignorant and premeditated action. 
 
Source: Hulme P., Bacher S., Kenis M., Klotz S.,  Kühn I., Minchin D., Nentwig W., Olenin S., 
Panov V., Pergl J., Pysek P., Roque s A., Sol D., Solarz W., Vilà M., Grasping the routes of 
biological invasions: a framework fo r integrating pathways into policy , Journal of Applied 
Ecology,  
EN 43   EN Figure 4 shows the increasing invasion trends 
 
Source: DAISIE project 050010001500200025003000
1500 1600 1700 1800 1900 2000
Date of introductionNo. of speciesAlien to Europe
Alien in EuropeAliens of European origin 
EN 44   EN Figure 5 shows the  temporal trends in the mode of introduc tion of (a) terrestr ial plants and (b) 
marine species in Nordic countries  
 
Sources: Data from the North European and Baltic Network on Invasive Alien Species 
http://www.nobanis.org/, accessed on 10/01/2007). 
EN 45   EN Figure 6  demonstrates the role of e-journal Aquatic Invasions in the developing European 
early warning system on inva sive alien species (IAS). 
 
Role of e-journal Aquatic Invasions in the developing European early warning system on invasive alien species (IAS), modified from Panov 
and Gollasch (2006). GISD – Global Invasive Species Database ( http://www.issg.org/database/ ), DAISIE - EC FP6 Strategic Targeted 
Research Project “Delivering Alien Invasive Species  Inventories for Europe” information resources ( http://www.europe-aliens.org ), 
ERNAIS – European Research Network on Aquatic Invasive Species ( http://www.zin.ru/rbic/projects/ernais/ ), RBIC – Regional 
Biological Invasions Centre  information system ( http://www.zin.ru/rbic/ ), EurOBIS - The European Oc ean Biogeographic Information 
System ( http://www.marbef.org/data/eurobis.php ), ICES – International Council for the Exploration of the Sea ( http://www.ices.dk ), 
NOBANIS – North European and Baltic Ne twork on Invasive Alien Species ( http://www.nobanis.org/ ); AES CIESM – Atlas of Exotic 
Species of the International Comm ission for the Scientific Explora tion of the Mediterranean Sea ( http://www.ciesm.org/online/atlas/ ), EC – 
European Commission ( http://ec.europa.eu/ ), EEA – European Environment Agency ( http://www.eea.europa.eu/ ), OSPAR - OSPAR 
Commission for the Protection of the Marine Environment of the North-East Atlantic ( http://www.ospar.org/ ), HELCOM – Baltic Marine 
Environment Protection Commission (http://www.helcom.fi/ ), Risk Assessment Toolkit – online risk assessment instrument with early 
warning functions currently under development in frameworks  of EC FP6 Integrated Project ALARM (Panov et al. 2008) 
Source: Panov V. et al, " New electronic journal "Aquatic In vasions": an important part of 
the developing European early warning system on aquatic invasive species ", ALARM 
deliverable D 5.1.7 Feb 2008 
EN 46   EN Figure 7 and Figure 8 show selected new geo-referenced re cords of invasive alien species in 
European inland waters in 2006-2007, pub lished in the second volume of Aquatic Invasions 
Figure 7 
 
Selected new geo-referenced records of invasive alien species in European inland waters in 2006-2007, published in the second v olume of 
Aquatic Invasions: 1 – the spiny-cheek crayfish, Orconectes limosus in UK (Holdich and Black 2007), 2 – the Ponto-Caspian amphipod 
Dikerogammarus villosus (“killer shrimp”) in Lac du Bourget, France (G rabowski et al. 2007), 3 – the Quagga mussels Dreissena bugensis 
in the Main River, Germany (van der Veld e and Platvoet 2007), 4 – the Quagga mussels Dreissena bugensis in Ukraine (Son 2007), 5 – the 
tubenose goby Proterorhinus marmoratus from the River Pripyat, Belarus (Rizevsky et al. 2007), 6 – the tubenose goby Proterorhinus 
marmoratus from the Neva River estuary, Russia (Antsu levich 2007), 7 - the Ponto-Caspian amphipod Dikerogammarus villosus in the 
Dnieper River, Belarus (Mastitsky and Makarevich 2007), 8 – the North American freshwater limpet Ferrissia fragilis in Ukraine (Son 
2007), 9 – the parasite trematode Rossicotrema donicum from Lake Lukomskoe, Belarus (Mastits ky 2007), 10 – the Ponto-Caspian mysid 
Limnomysis benedeni from the River Pripyat, Belarus (Semenche nko et al. 2007), 11 – the Chinese mitten crab, Eriocheir sinensis from the 
Volga River, Russia (Shakirova et al. 2007), 12 – the Asian clams Corbicula fluminea and C. fluminalis in Serbia (Paunovi ć et al. 2007), 13 
– the Asian clam Sinanodonta woodiana from Eastern Romania (Popa et al. 2007), 14 – the North American sunfish Lepomis gibbosus in 
Turkey (Özcan 2007) 
Source: Panov V. et al, " New electronic journal "Aquatic In vasions": an important part of 
the developing European early warning system on aquatic invasive species ", ALARM 
deliverable D 5.1.7 Feb 2008  
EN 47   EN Figure 8 
 
Selected new geo-referenced records of invasive alien species in European coastal waters in 2006-2007, published in the second volume of 
Aquatic Invasions: 1 – the Asian bivalve Theora (Endopleura) lubrica from Mediterranean coast of Israel (Bogi and Galil 2007), 2 – the 
Indo-Pacific humpnose big-eye bream, Monotaxis grandoculis in the Mediterranean Sea (Bilecenoglu 2007), 3 - the Red Sea mussel 
Brachidontes pharaonis from the Turkish coasts (Do ğan et al. 2007), 4 - the red alga Asparagopsis taxiformis in Greece (Tsiamis and 
Panayotidis 2007), 5 - the tropical scyphomedusa Phyllorhiza punctata in the Central Mediterranean Sea (Abed-Navandi and Kikinger 2007), 
6 - the oriental shrimp Palaemon macrodactylus in Gironde Estuary, France (Beguer et al. 2007), 7 – the Pacific alga Sargassum muticum on 
the west coast of Scotland (Harries et al. 2007), 8 – the Asian amphipod Caprella mutica in coastal waters of UK and Norway (Cook et al. 
2007), 9 - the American oyster drill, Urosalpinx cinerea in The Netherlands (Faasse and Ligthart 2007), 10 – the Asian tunicate Styela clava 
from the central German Bight (Krone et  al. 2007), 11 – the North-American ctenophore Mnemiopsis leidyi in Danish waters (Tendal et al. 
2007), 12 – Mnemiopsis leidyi in the Oslofjorden, Norway (Oliveira 2007), 13 - Mnemiopsis leidyi in south-western Baltic Sea ( Kube et al. 
2007), 14 - Mnemiopsis leidyi in the Gulf of Gda ńsk, southern Baltic Sea ( Janas and Zgrundo 2007), 15 - Mnemiopsis leidyi in the north-
eastern Baltic Sea (Lehtiniemi et al. 2007) 
Source: Panov V. et al, " New electronic journal "Aquatic In vasions": an important part of 
the developing European early warning system on aquatic invasive species ", ALARM 
deliverable D 5.1.7 Feb 2008 
EN 48   EN Figures 9-12  proportion of different taxonomic groups  listed according to 4 different 
introduction categories (see also table 5)  
Figure 9:  Proportion of different taxonomic groups lis ted as category A (species introduced 
intentionally as the commodity itself for being released into the environment, n = 77 species) 
Crustaceans 
10.4%
Insect
1.3%
Macroalgae
1.3%Plants
51.9%Birds
1.3%Amphibians & 
Reptiles
1.3%Fish
16.9%
Mammals
6.5%
Molluscs
9.1%
 
Figure 10:  Proportion of different ta xonomic groups listed as category B (species introduced 
intentionally as the commodity itself for bei ng kept in a controlled environment, n = 45 
species) 
Plants
24.4%
Macroalgae
2.2%
Comb jellies
4.4%
Amphibians & 
Reptiles
6.7%Birds
13.3%Crustaceans 
11.1%Fish
6.7%Mammals
20.0%Molluscs
11.1%
 
EN 49   EN Figure 11:  Proportion of different taxono mic groups listed as categ ory C (sp. Unintentionally 
introduced as a contaminant of a specific commodity : n = 205 species) 
Plants
15.1%Insect
65.4%
Fungi
4.4%
Protists
0.5%Annelids
0.5%Nematodes
6.3%Molluscs
2.4%Hydroids, Jellyfish, 
Sea Anemones & 
Corals
0.5%Flatworms
2.0%
Cestoda
0.5%Macroalgae
2.4%
 
Figure 12:  Proportion of different taxono mic groups listed as categ ory D (sp. Unintentionally 
introduced with movements of people or of machinery; n = 131 species) 
Plants
14.5%
Insect
24.4%Prokaryotes
0.8%Macroalgae
4.6%Mammals
0.8%Molluscs
7.6%Nematodes
9.2%Phytoplankton
7.6%
Fungi
0.8%Fish
8.4%Crustaceans
8.4%Bryozoans
1.6%Ascidians and 
Sessile Tunicates
0.8%Annelids
6.1%
Protozoa
1.6%
Hydroids, Jellyfish, 
Sea Anemones & 
Corals
2.3%Comb Jellies
0.8%
 
Source : Genovesi P, Scalera R, Towards a Black List of Inva sive Alien Species Entering 
Europe Through Trade and Proposed Responses , document prepared the Convention on the 
Conservation and European Wildlife and Natural Habitats, November 2007 
EN 50   EN Table 1:  Examples of pathogens and parasites transmitted to native hosts following the 
introduction of specific alien species into Europe 
Taxon Alien host Native host Alien parasite/pathogen 
Plants Rhododendron ponticum Quercus petraea Sudden oak death fungus 
Crustacea Pacifastacus leniusculus Austropotamobius pallipes Crayfish plague fungus 
Insects Apis cerana Apis mellifera Varroa mite 
Fish Pseudorasbora parva Leucaspius delineatus Rosette agent parasite 
Fish Anguilla japonica Anguilla anguilla Swim-bladder nematode 
Mammals Cervus nippon Cervus elaphus Asiatic blood nematode 
Mammals Mustela vison Mustela lutreola Aleutian disease virus 
Mammals Sciurus carolinensis Sciurus vulgaris Parapox virus 
 
Source: Hulme P. Biological Invasions in Europe: Driver s, Pressures, States, Impacts and 
Responses , The Royal Society of Chemistry, 2007 
EN 51   EN Table 2:  Monetary costs (million € per year) of alien species invading Europe 
 
References to Table 2 
Adrados LC and Briggs L (Eds). 2002. Study of application of EU Wildlife Trade regulations in re lation to species which form an  
ecological threat to the EU fauna and flora, with case studies of American bullfrog ( Rana catesbeiana ) and red-eared slider 
(Trachemys scripta elegans ). Study report to the European Commission. Amphi Consult, Denmark. 
Andreu J and Vilà M. 2007. Análisis de la gestión de la s plantas invasoras en España. Ecosistemas 3: 1-16. 
Alonso C. 2006. La CHE ya cualifica los daños del mejillón cebra en 2 millones anuales. El  Periodico September 19. 
Child L, Wade M, and Hathaway S. 2001. Strategic invasive plant management, linking policy and practice: A case study of 
Fallopia japonica in Swansea, South Wales (United Kingdom). In: Brundu G, Brock J, Camarda I, Child L, Wade M (Eds.). Plant 
invasions: Species ecology and ecosystem managem ent. Backhuys Publishers, Leiden, The Netherlands. 
Galil BS and Zenetos A. 2002. Invasive aquatic species of Eur ope: Distribution, Impacts and Management. In: Leppäkoski E, 
Gollasch S, Olenin S (Eds). Kluwer Academic Publishers, Dordrecht, The Netherlands, pp 
Gebhart H. 1996. Ecological and economic cons equences of introductions of exotic wild life (birds and mammals) in Germany. 
Wildl Biol 2: 205-11. 
Gollasch S and Rosenthal H. 2006. The Kiev Canal. In: Gollasch S, Galil BS, Cohen A (Eds). Bridging divides-maritime canals 
as invasion corridors. Spirnger, Dordrecht, The Netherlands 
EN 52   EN Gosling LM and Baker SJ. 1989. The eradication of muskrat s and coypus from Britain. Biol J Linn Soc 38: 39-51. 
Gritten RH. 1995. Rhododendron ponticum and some other invasive plants in the Snowdonia National Park. In: Pyšek P, Prach 
K, Rejmánek M, Wade M (Eds). Plant in vasions: General aspects and special problems. SPB Academic Publishing, Amsterdam. 
Hentschel W and Hentschelová H. 2003. Vejm utovka v Labských pískovcích. In: Nep ůvodní dřeviny a invazní rostliny, sborník 
přednášek z celostátního seminá ře, Žlutice, zá ří 2003, Česká lesnická spole čnost, Moldau Press Praha: 85-98 
Hopkins 2002. In: Leppäkoski E, Gollasch S, Olenin S (Eds.). Inva sive aquatic species of Europe:  Distribution, Impacts and 
Management. Kluwer Academic Publishers, Dordrecht, The Netherlands, pp 
Křivánek M. 2006. Biologické invaze a možnosti jejich p ředpovědi (Predik ční modely pro stanovení invazního potenciálu vyšších 
rostlin). Acta Pruhoniciana vol 84, VÚKOZ Pr ůhonice, 83 pp 
Moore NP, Roy SS, and Helyar A. 2003. Mink ( Mustela vison ) eradication to protect ground-nesting birds in the Western Isles, 
Scotland, United Kingdom. N Z J Zool 30: 443 – 452. 
Nielsen et al 2005. 
Panov PI, Krylov and I. V. Telesh. 1999. In: Initial risk a ssessment of alien species in Nordic coastal waters 
Panzacchi M, Bertolino S, Cocchi R, et al. 2007. Population control of coypu Myocastor coypus in Italy compared to eradication 
in UK: a cost-benefit analysis. Wildl Biol 13: 159-171. 
Scalera R and Zaghi D. 2004. Alien species and nature conservation in the EU. The role of the LIFE program. LIFE Focus. 
European Commission, Bruxelles. 
Shaw RH. 2003. Biological control of invasive weeds in the UK: opportunities and challenges. In: Child LE, Brock JH, Brundu G, 
Prach K, Pyšek P, Wade PM and Williamson M (Eds). Plant  invasions: Ecological threaths and management solutions. 
Backhuys Publishers, Leiden. 
Smallshire D, Davey JW. 1989. Feral Himalayan porcupines in De von. Nature in Devon, J. Devon Wildl. Trust. 10: 62-69. 
White PCL and Harris S. 2002. Economic and environmental costs of alien vertebrate species in Britain. In: Pimentel D. 
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Williamson M. 2002. Alien plants in the British Isles. In D Pi mentel Biological invasions: economic and environmental costs of 
alien plant. Animal and microbe species. CRC Press, Boca Raton. 
Source: Vilá M. and Basnou C., State of the art review of the environmental and economic 
risks posed by invasive alien species in Europe , DAISIE deliverable 14, February 2008 
EN 53   EN Table 3:  Estimated monetary costs (million € per year) of alien species invading Europe 
 
References to Table 3 
Collins V. 2006. £100.000 battle against alien crayfish ends in def eat. Crayfish News-International Association of Astacology 
Newsletter 28: 219-226. 
Knowler D. 2005. Reassessing the cost of biological invasion: Mnemiopsis leidyi in the Black Sea. Ecol Econ 52: 187-199. 
Leppäkoski E, Olenin S, and Gollasch S. 2002. The Baltic Sea - a Field Laboratory for Invasion Biology. In: Leppäkoski E, 
Gollasch S, Olenin S (Eds). Invasive aquatic species of Europe: Distribution, Impacts and Management. Kluwer Academic 
Publishers, Dordrecht, The Netherlands. 
Pimentel D, McNair S, Janecka J, et al . 2001. Economic and environmental threats of alien plant, animal, and microbe 
invasions. Agric Ecos Environ 84: 1-20. 
Prus J. 1997. New methods of risk assessment for the rel ease of transgenic plants. PhD T hesis, Cranfield University. 
Reinhardt F, Herle M, Bastiansen F et al . 2003. Economic impact of the spread of alien species in Germany. Federal 
Environmental Agency (Umweltbundesamt), Berlin, Germany. 
Travis J. 1993. Invader threatens Bl ack, Azov Seas. Science 262: 1366-1367. 
Williamson M. 2002. Alien plants in the British Isles. In D Pi mentel Biological invasions: economic and environmental costs of 
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Source: Vilá M. and Basnou C., State of the art review of the environmental and economic 
risks posed by invasive alien species in Europe , DAISIE deliverable 14, February 2008 
EN 54   EN Table 4:  Examples of situations where major econom ic sectors act as sources of alien species 
in Europe and the problems that alien species (from all sources) causes within these particular 
sectors 
Sectors Sector as source of alien taxa Aliens as sector problems 
Agriculture Feral Crops: Linum usitatissimum  Agricultural Weeds: Oxalis pescaprae  
 Nectar/Pollen Sources: Impatiens glandulifera  Contaminated Seed: Amaranthus retroflexus  
 Alien Pollinators: Bombus  spp. Hive Parasites: Varroa destructor  
 Fur Farms: Mustela vison  Vertebrate Pests: Nyctereutes procyonoides 
Aquaculture Fish Stocking: Salvelinus alpinus  Alien Pathogens: Spring viraemia 
Energy Biomass Crops: Miscanthus chinensis  Cooling System Fouling: Dreissena polymorpha  
Health Medicinal Herbs: Tanacetum parthenium Allergenic Pollen: Ambrosia artemisifolia  
  Toxic Sap: Heracleum mantegazzianum  
  Disease Vectors: Rattus rattus  
Horticulture Garden Plants: Mimulus guttatus  Garden Weeds: Aegopodium podagraria  
 Landscaping: Robinia pseudoacacia Urban Weeds: Ailanthus altissima  
Industry Imported Raw Materials: Senecio squalidus Development Constraint: Fallopia japonica  
 Pet Industry: Trachemys scripta elegans   
Mariculture Mariculture escapes: Crassostrea gigas  Alien Parasites: Mytilicola orientalis  
Silviculture Plantation Exotics: Pinus contorta  Forestry Weeds: Prunus serotina 
 Plantation Pests: Anoplophora glabripennis Forestry Pests: Sciurus carolinensis  
Tourism Zoological Gardens: Muntiacus reevesi Hybridisation with Natives: Oxyura jamaicensis  
 Botanical Gardens: Hedychium gardnerianum  Biodiversity Loss: Rhododendron ponticum  
 Sports Fishing: Oncorhynchus mykiss Fishing Tackle Foulant: Cercopagis pengoi  
 Game Introductions: Sylvilagus floridensis  
Transport Ballast Water: Eriocheir sinensis  Hull fouling: Caprella mutica  
  Air Strikes: Branta canadensis  
Water Freshwater transference: Dreissena polymorpha Alien macrofoulants: Corbicula fluminea  
Source: Hulme P. Biological Invasions in Europe: Driver s, Pressures, States, Impacts and 
Responses , The Royal Society of Chemistry, 2007 
EN 55   EN Table 5:  Number of species classified by the following trade categories: A) the alien 
species is intentionally introduced, as the co mmodity itself, for being released into the 
environment (i.e. game species, freshwater fish, tree species of interest for forestry, biocontrol 
agents, etc.) B) the alien species is intentionally introduced as the commodity itself (i.e. ornamental plants, agricultural plants, pets, cray fishes, etc.) in a containment facility or in a 
controlled environment (i.e. bot anic gardens, greenhouses, ag ricultural land, zoos, animal-
breeding establishments, fish farms, etc.). C) th e alien species is unintentionally introduced as 
a contaminant of a specific commodity (i.e . Anoplophora chinensis introduced in Italy 
through import of bonsai; parasites of specific fi sh species, fruit flies, microcell disease 
Bonamia ostreae transported with oyster shipments,  etc) D) the alien species is unintentionally 
introduced with movements of people or of machinery (i.e. pests in wood packaging, hull 
fouling, ballast waters, contaminants in containers, hitchhikers on planes, etc.). 
(See also figures 5-8) 
 
Source : Genovesi P, Scalera R, Towards a Black List of Invasive Alien Species Entering 
Europe Through Trade and Proposed Responses , document prepared the Convention on the 
Conservation and European Wildlife and Natural Habitats, November 2007  
EN 56   EN Table 6:  List of pathways of IAS introductions in Europe with descriptors for assessment of 
pathways (Minchin et al. 2007, modified) 
Pathway  Vector  Descriptor of operating pathway  
1. Ships, moveable structures  
(barges, dredgers, floating docks, 
navigation buoys) fish ing, leisure vessels, 
floatplanes and small sports craft (jet skis, 
canoes, paddle craft)  • Water and sediments carried within ballast 
tanks 
• Rock and sedimentary ballast 
• The hull including projections, intakes and 
cavities of the hull (s ea chests, thruster 
ports and fans, abstraction piping and 
small crevices) 
• Boring organisms of the hull and other 
submerged structures 
• Bilges and bilge pumping equipment 
• Wells, tanks and with other cargo 
• Anchor, anchor chains, lockers, fenders, 
portable moorings and recesses in the deck 
and holds 
• Trailers for the transportation of craft and 
all adhering and snagged organisms 
• Dredged materials, coarse gravel 
extractions to disposed fine sediments  • Regular passage of ships or port within the 
assessment unit  
2. Canals (including irrigation channels, 
drainage cuts, and cuts, ponds and marina basins) 
 • Water flow, tidal exchanges, flooding 
events, storm surges or varying water levels 
• Transport of floating timber, pontoons, 
other equipment 
• Associated with migrating aquatic species 
• Leakage of water from aquaducts • Presence of the canal within assessment 
unit or within inla nd waterway/invasion 
corridor AU belongs to.  
3. Wild fisheries 
 • Stock movements 
• Population re-establishment 
• Discharges from processing live, fresh and 
frozen foods 
• Live bait releases and discharges of live 
packaging materials 
• Movements of retrieved fishing 
equipment, discarded or lost nets, floats, 
traps etc. 
• Discards of target and non-target species 
(bycatch) 
• Releases of organisms intended as living 
fish food supplements   
EN 57   EN Pathway  Vector  Descriptor of operating pathway  
4. Culture activities 
 • Intentional releases and movement of 
stock and associated water 
• Unintended or unauthorised releases 
(including from secure fur-farms) 
• Movement of equipment (nets, cages, 
lines, pumping equipment, etc.) 
• Discarded contaminated containers, live 
packaging materials and/or associated transport media 
• Broadcasting feeds (live, fresh, frozen) 
• Release of genetically modified species  • aquaculture is practiced within the 
catchment area 
• Stock enhancement known to take place 
within assessment unit 
5. Ornamental and live food trade  
including garden centres and public 
aquaria)  
 • Intentional releases (in particular releases 
from aquaria and ponds) 
• Accidental releases (including from 
ornamental breeding and of incorrectly 
identified species) 
• Movement of organisms associated with 
stones (‘live rocks’), corals, gravels and 
sediments 
• Untreated waste discharges • Unauthorised releases of imported living 
foods  • Tropical species known to be in cultivation 
and released to thermal effluents where ‘permanent’ populations may form 
 
 
  
 
 • Holding tanks for imported foods adjacent 
to assessment area  
6. Leisure activities 
 • Live bait movements and discharges of 
live packaging materials 
• Accidental, intentional transport and 
release of angling catch 
• Water sport equipment (diving , fishing 
gear) 
• Live souvenirs, fairground prizes • marina or marinas within assessment unit 
or leisure craft visit assessment unit 
• high human activity with festivals and 
sporting events (including angling 
involving live bait releases) with provided 
access via public parks  
7. Research and education (including pilot 
projects) 
 • Intentional releases involved in field 
experiments, including translocations 
• Accidental release 
• Waste water and biological waste 
discharges (including flow-through 
aquaria systems, discarded demonstration 
materials) 
• Living food releases from cultures or 
movements 
• Field and experimental gear movement 
(including diving gear) 
• Caged organisms used for monitoring 
water quality  • releases of experimental organisms are 
known  
EN 58   EN Pathway  Vector  Descriptor of operating pathway  
8. Biological control  • Releases to control invasive or otherwise 
abundant organisms 
• Releases to reduce impacts of diseases and 
parasites  • Biological control activities are known  
9. Alteration to natural water flow  • Movements of abstracted water for 
municipal supply (from watering channels 
to piped and pumped supplies) 
• Drainage to different river catchments 
• Irrigation channels 
• Development of reservoirs with overspill 
to different catchments 
• Removal of natural barriers between 
catchments   
10. Other pathways  • Habitat management (soil stabilisation/ 
reclaimation using rock barriers, sediments 
and plantings; use of filterfeeding invertebrates for managing water quality) 
• Municipal and other waste treatment 
discharges 
• Discharged live packing material used for 
non-living products 
• Releases of transported water (drinking 
water for humans and/ or livestock and 
associated equipment)  • Sand and gravel extraction known to take 
place in assessment unit. Organic waste 
known to be released to assessment unit (from food processing plants)  
 
Source: Panov V.et al, Interim protocols for risk assess ment of aquatic invasive species 
introductions via European inland waterways , ALARM deliverable D. 4.1.3.10, February 
2008-06-04  
EN 59   EN ANNEX B - Relevant EU research projects  
DAISIE, a pan-European in ventory of alien species  (see http://www.europe-
aliens.org/index.jsp ) a 3 year (February 2005-March 2008 ) research project supported under 
the 6th RTD Framework programme with 2.4 million €, delivered a pan-European inventory 
of invasive alien species mobilising existing expe rtise for species records. This inventory also 
includes and describes alien species that have a high likelihood of intr oduction or spontaneous 
spread from neighbouring countries, and identifies priority species. 
DAISIE focused on four major areas of in formation gathering and dissemination: 
1) European Alien Species Expertise Registry  
Current expertise in biological  invasions is distributed acr oss research organisations 
throughout Europe and is funded mainly by na tional programmes. The European Expertise 
Registry represents a fundamental step toward s linking these organisati ons and individuals in 
ways that provide added value at European leve l and provide the critical  mass of expertise in 
invasive alien species research to meet Eur opean-scale requirements. The European Expertise 
Registry facilitates the cl ustering and information sh aring among different national 
programmes targeting the same invasive alien species, helps establish teams of experts who 
can, once a new alien incursion has been reported, assess the s ituation and prepare an action 
plant for the invasive alien species at a partic ular site and enables the current breadth and 
scope of European knowledge on alien specie s to be assessed. The registry contains 
information on the field of e xpertise (distribution, conser vation, ecology, economy, genetics, 
legislation, management, pathways, physiology, risk assessment, and taxonomy) and on the 
taxonomic and geographic structure of the expe rtise.. Within 12 months of its launch, the 
Registry contained information on 1500 experts from nearly 90 countries for almost 3000 
higher taxa (family level or higher) and numbers have steadily increased since. 
2) European Alien Species Database  
An up-to-date inventory of all alien species known to inhabit Europe represented the major 
activity in DAISIE and involved compiling and peer-reviewing national lists of hundreds of 
species of fungi, plants, invert ebrates, fish, amphibians, rep tiles, birds and mammals. Data 
were collated for all 27 European Union member  states, and where thes e states had significant 
island regions, data were collated separately for these as well. In addition, data were collated for European states that are not in the European Union such as Andorra, Iceland, 
Liechtenstein, Moldova, Monaco, Norway, Russia,  Switzerland, Ukraine as well as former 
Yugoslavian states in the Balkans. Finally, ma rine lists were referenced to the relevant 
maritime state and thus to have full coverage of  the Mediterranean, marine data were included 
for North African and Near East  countries. For each species, an attempt was made to gather 
information on native range, date of introduc tion, habitat, known impacts and population 
status. Considerable effort was required to ensure synonyms were accounted for accurately 
and all national lists were independently revi ewed by experts. Records of over 10,000 alien 
species are included in the database (February 2 008), the majority of records are for vascular 
plants with invertebrates also a signifi cant component (see Olenin et al. 2008). 
EN 60   EN 3) European Invasive Alien Species Information System  
The provision of selected species accounts c overing high profile alien species not only 
delivers end users with relevant details for sp ecies identification and management but also 
helps raise public awareness of the issue of invasions. Accounts for representative sample of 
100 invasive alien species have been produ ced and each includes information on biology, 
ecology, distribution, management information, re ferences, links and images. The aim was to 
generate brief fact sheets that might appeal to the general reader with links to more detailed 
information for specialists. The accounts cover 3 fungi, 18 terrestrial plants, 16 terrestrial 
invertebrates, 15 verteb rates, 16 inland and 32 coastal aquatic species invading natural and 
semi-natural habitats. Selection was based on ensuring a broad spectrum of life forms and 
functional types, a range of i nvaded ecosystems and clear exam ples of different impacts on 
European biodiversity, economy and health (see Vilà et al. 2008). A key requirement for the 
effective management of invasive alien species  is the ability to id entify, map, and monitor 
invasions in order to assess thei r extent and dynamics (Hulme 2003). 
4) Species Distribution Maps and Spatial Analysis 
DAISIE had as an objective to establish a common European standard for the graphical 
presentation of the invasive alien species data as  distribution maps. The Common European 
Chorological Grid Reference System with the size of the mapping grid ca 50 × 50 km, 
depending on the latitude/longitu de was used to produce dist ribution maps. This scheme 
employs a reasonably detailed resolution for Europe and is commonly used for species 
mapping. Data sources included European-wide and national at lases as well as regional 
checklists. The following data were plotted fo r each species: (a) known presence of the 
species; (b) known absence. Where known, additi onal information on (c) species previously 
present but eradicated and (d) native distri bution, was also considered. Where precise 
information on distribution was missing but the species was known to occur in a country/region/district, the dist ribution in these administrative units was recorded and mapped 
by using hatching. A different format was adopted  for mapping invaders in aquatic habitats 
where linear distributions or maritime areas ne eded to be recorded. Distribution maps were 
generated for the 100 species for which accounts were produced and can be found in Vilà et al. (2008). 
Each of these 4 activities has been integrated  together as a single internet portal for 
information on European alien species
36. The inventory, accounts,  and distribution maps 
today provide the first qualified reference system on invasive al ien species for the European 
region. The information presents an outstanding resource to s ynthesise current knowledge and 
trends in biological invasions in Europe. The data will help identify the scale and spatial 
pattern of invasive alien speci es in Europe, understand the e nvironmental, social, economic 
and other factors involved in invasions, and can be used as a framework for considering 
indicators for early warning. In addition, the data will assist Member States develop and manage their National Biodiversity Action Plans as well as enable the European Union to 
monitor its performance towards the 2010 target.  
ALARM, Assessing large scale envi ronmental risks on biodiversity (see 
http://www.alarmproject.net
 ) is a 5 year (February 2004- March 2009) Integrated Project 
supported under the 6th RTD Framework programme with 13 million €. ALARM integrated 5 
                                                 
36 See http://www.europe-aliens.org/index.jsp  
EN 61   EN modules focussing on risks consequent on climate change, biological invasions, 
environmental chemicals, rates and extent of pol linator loss and socio-economic aspects in the 
context of current and future European land use. ALARM also looked at combined risks. One of the major outputs will be a Risk  Assessment Toolkit for biodiversity. 
ALARM currently supp ort the e-journals Aquatic Invasion
37 and Biorisk38. 
The journal "Aquatic Invasions" was established in 2006 as an initiative of the European 
Research Network on Aquatic Invasive Species (ERNAIS), with start-up  funding from the EC 
FP6 Integrated Project ALARM. It provides the opportunity for timely publication of first 
records of biological invaders for considera tion in risk assessments and early warning 
systems. Also, the journal provides the opport unity to publish technical reports on new 
technologies in management of invasive specie s and proceedings of re levant international 
meetings. In 2007, four issues  of the second volume of Aquatic Invasions with 62 research 
articles and short communications  were released and freely available at the journal website. 
These papers included 820 new geo-referenced r ecords of invasive alien species in European 
inland and coastal waters, with 168 records from field surveys in 2007. 
One of the key benefits of these e-journals is  the timely and readily available publication of 
essential primary scientific information39 also needed for decision making. The provision of a 
freely accessible, early warning system for potentia lly invasive alien species is an essential 
tool for decision-making to priori tise early eradication efforts, a nd also for relevant decision 
support systems. In addition online journals can provide a publication platform for other 
important information on the management of invasive species incl uding publication of 
technical reports on new technologies in manageme nt of invasive species and proceedings of 
relevant international meetings. Finally, the fast but comprehensive reviewing process of 
submitted manuscripts is serving as an effective quality insurance mechanism for IAS information that is freely availa ble to interested  stakeholders. 
                                                
 
37 See http://www.aquaticinvasions.ru/  
38 See http://www.pensoft.net/Brochure-BIORISK.pdf  
39 A manuscript publication, including a comprehensiv e review process, takes on average less than one 
month, thereby reducing the publication time lag typical  of many regular international journals. In this 
way Aquatic Invasions can facilitate the regional and Pan-Eu ropean early warning systems on alien 
species, previously lacking. 
EN 62   EN ANNEX C - Examples of costs and benefits of IAS policy measures  
Taking a policy measure for IAS entails costs, po ssibly very substantial, which need to be 
offset against the costs of inact ion or delayed intervention to c ontrol IAS. There is a growing 
body of evidence that the benefits of preventi ve action on IAS often outweigh the costs of 
inaction (even when these are only partially as sessed e.g. the stated economic impact does not 
reflect all or any damage to ecological, recreational and cultural values).  
In the following examples of costs and benefits  associated with the IAS policy options are 
listed. Because monetary cost information is lack ing for Europe in many cases, some points of 
reference are provided from other jurisdictions where appropriate. 
The selected examples are loosely grouped for ea se of reference but th is should not be taken 
as a formal classification as many of the IAS mentioned could fall into more than one group.  
IAS threatening native species and communities 
Lithobates catesbeianus  (American Bullfrog) . UK early eradication efforts cost 32,000 €. 
Complete removal of all individuals (includi ng tadpoles) may involve drainage of the water 
body where they are present which is extremely costly. Current control costs known in EU Member States are 0.4 million €/year (Germany, 0.39; UK eradication 0.01).  
Oxyura jamaicensis  (Ruddy duck).  The UK eradication progr amme (established 1992 to 
reduce the population to less than 175 birds, or 5 % of 1999 population) cost an  estimated 4.4 
million € over a 4-6 year period. It combines a general authorisation for landowners to shoot 
specimens at any time of the year, subject to a reporting requirement to the relevant ministry, 
and subjects purchase and sale of specimens to a permit requirement (no permits issued for several years). By 2004, at least 15 countries in the Western Palearctic were implementing 
control measures and about 5,500 birds have been culled (UK 5,100; France, 246 since 1998; Spain, 217 since 1993). Control cost figures  not available for these countries. 
Impatiens glandiflora  (Himalayan balsam) is invasive in almost all temperate European 
countries and may outcompete na tive plants for pollinators (bees), thereby reducing native 
plant seed production. Eradication is costly and time consuming because of the high ability of 
the species to regenerate and spread, includ ing through river corridors. The UK Environment 
Agency estimates eradication costs fo r England and Wales at 210-240 million €. 
IAS policies may support higher investment in control where eradica tion is technically 
feasible and high biodiversity va lues require protection (e.g. nativ e birds on isolated islands at 
risk from introduced rats and ot her vertebrates). Over the last 15 years, rat eradications have 
been successfully completed on increasingly la rger offshore islands, i.e. Langara Island 
(British Colombia, Canada, 3100 ha), Raoul Is land (2938 ha) and Little Barrier Island (3083 
ha) (New Zealand). 
IAS affecting multiple sectors due to im pacts on ecosystem function and services 
Myocastor coypus  (coypu) . In Italy (1995-2000), removal of over 220 thousand coypus cost 
2.614 million € whilst riverbank damage exceeded 10 million € and agricultural damage was almost 1 million €. Current control costs availa ble for EU Member States total 5.02 million 
€/year (Netherlands: preventio n/control 0.8 million; East Anglia (UK): eradication 0.45 
million; Italy: combined damage /control costs, 3.77 million).  
EN 63   EN Ondatra zibethicus  (muskrat) . In Germany, eradication cost s are estimated at 3 million 
€/year whilst the estimated cost of damage to inland water systems is 12.4 million €/year (4.6 million for sanitary aspects; 2.3 million for wate rway maintenance, 1.9 million in losses to 
hatcheries and fishfarms th rough damaged ponds and dams). 
Mustela vison  (American mink) . Damage costs in Germany estimated at 4.2 million €/year 
to agriculture (free-range poultr y), hunting (reared game birds) , fisheries (salmon farming) 
and eco-tourism (predation on gr ound nesting birds). Current co ntrol costs available for EU 
Member States are as follows: UK, eradication 0.55 million €/year
40; Estonia 
control/eradication, 0.12 million €/year; France: control/eradication 0.29 million €/year). In 
Sweden, an intensive mink hunting progr amme under the National Action Plan for 
conservation of the Caspian tern Hydropogne caspia  (2007-2011) will cost the Swedish 
Environmental Protection Agency 500,000 SEK (2007 prices) over that period for five areas 
totalling approximately 200 km2. 
Fallopia japonica  (Japanese knotweed) . Extremely high damage and control costs due to 
breadth of impacts, including da mage to masonry, pavements,  walls, drainage works and 
native riparian communities, increased flood risk  and increased cost of land clearance for 
development (where the plant occurs on a development site it can cost tens of thousands of pounds to adequately control). In Germany, estimated costs are 5.9-6.6 million €/year (plant control), 12.3-21.2 million €/year (stabilisation of river banks), 2-7.7 million €/year (clearance 
of railways) and 3.5-10.5 million €/year (repai r of foundations). The Czech Republic spends 
0.2 million €/year on control/containment. In the UK, a 2003 estimate put cost of removal 
from Britain at £1.56 billion. Specific control costs cover attempted eradication (over 1078 million €/year) and research on biocontrol (0.11 m illion €/year). In Wales (UK), the estimated 
annual control costs for one county council in 1994 was £300,000. 
Invasive aquatic plants affe cting inland water systems 
Several ornamental aquatic plants that have proliferated in inland water systems can block 
waterways by forming dense vegetation mats on the surface, thus reducing oxygen and light 
penetration into the water column and negatively affecting fish life, plants and invertebrates. 
Depending on the species and recipient ecosyste m, socio-economic impacts include reduced 
opportunities for angling, interf erence with navigation, increa sed flood risk and clogged 
intakes of irrigation, hydropower and water suppl y systems. Control in aquatic ecosystems 
presents technical difficulties e.g. physical re moval results in many small viable fragments 
being left in the water, which may spread the plant downstream or elsewhere within lakes and 
reservoirs.  
Examples of known control costs: Nymphoides peltata  (Yellow floating heart) . Total potential costs of controlling the yellow 
floating heart in Swedish lakes assessed at 28-72.8 million SEK/year, assuming 800-1,300 
hectares treated at 35,000-56,000 SEK per hectare; 
Hydrocotyle ranunculoides  (Floating pennywort) : Netherlands, 3 million €/year; 
                                                
 
40 In 1965-1970, an unsuccessful eradication (trapping) campaign by the Agriculture Ministry of Agriculture cost 
£105,000: the cost at 1990 prices, excluding associated re search costs, was estima ted at £552,000 (see annexed 
Table).  
EN 64   EN Crassula halmsii  (New Zealand Pigmyweed) : UK estimated costs  0.895 million €/year. 
Little monetary cost informati on is available for Europe on Azolla filiculoides  (Red water 
fern) , a native of South America. However, the plant is well-documented in South Africa 
where associated damages (coverage of dams, resulting damage to water pumps; deaths of livestock; substantial clearing costs) are estimated at 580 million Rand. One study on the economic benefits of developing biol ogical control showed that bringing Azolla filiculoides  
under control yielded a return on investment of 25 :1. Cost of damage was compared to cost of 
research (510 000 Rand) that led to the rele ase of the biocontrol agent which brought the 
problem completely under contro l within 2 years of release.
41 
Invasive terrestrial plants that reduce available water resources  
Some invasive alien plants consume a higher proportion of available water resources than 
native plants in the same ecosystem. Reduced r unoff from watersheds w ith dense stands of 
invasive trees can affect biological pr oduction sectors, human wellbeing and native 
biodiversity. In such cases, costs of policy in tervention can be assessed at least partly by 
reference to financial benefits that w ould result from improved water yield.  
Eucalyptus spp  (Eucalyptus)  replaces natural vegetation and use excessive water in Spain, 
which currently spends 1.58 million €/year on c ontrol/eradication. Figures from South Africa 
assessed the costs of initial clearing of 2,264 ha at 5.02 mill ion Rand for one year (2002-
2003) with herbicides costing 992 Rand per hectare. 
IAS affecting forest pro ductivity and biodiversity  
Sciurus carolinensis  (Grey squirrel) . UK estimated costs of control and eradication are 0.46 
million €/year (mechanical and chemical me asures, research in to immunocontraceptive 
agents). Ongoing control costs are not available for Italy where a proposed rapid eradication 
programme was blocked by a lega l challenge from animal right s movements. Damage costs 
are available for the UK. In 1999, lost timber re venue at the end of a rotation in state-owned 
forests in England and Wales was estimated  at £2 million (Forestry Commission). In 2000, a 
Great Britain-wide study assessed total cost to  the British timber industry of damage to beech, 
sycamore and oak as £10 million at the end of the current rotation.  
Prunus serotina  (Black cherry) . In the Netherlands, control costs are 2 million €/year. In 
Germany, total damages and costs amount to 27 .50 million €/year (increased labour costs for 
forest management e.g. thinning, 1.4 ; direct control of pest in fo rests 20.7; control measures in 
nature conservation areas, 3.4). 
Rhododendron ponticum  (Rhododendron) . Current UK expenditures total 68.37 million 
€/year (technical difficulties both with mechani cal and chemical contro l, no biocontrol agent 
identified for Europe). Estimated costs of rhododendron removal from woodland in mainland 
Argyll and Bute £9.6 million; control costs to date in Snowdonia National Park £45 million.  
                                                 
41 National Biodiversity Strategy and Ac tion Plan (NBSAP). 2004. Towards a Na tional Strategy for Dealing with 
Invasive Alien Species in South Africa: Stocktaki ng Report. [Accessed 23 April 2008] Available online at: 
http://www.environment. gov.za/ProjProg/ProjProg/2004Jun10/stocktak ing/IAS_DRAFT_report_2004.doc#_Toc93
118802  
EN 65   EN Pests affecting forests include the fungus Ophiostoma novo-ulmi  (Dutch elm disease): control 
costs in Germany for removing dead trees, replan ting and loss of wood assessed at an average 
of 5 million €/year.  
Figures from the United States give an indicati on of the potential magnitude of forest pests: 
for Sirex noctilio  (woodwasp) and the asso ciated pathogenic fungus, Amylostereum 
areolatum , the USDA Forest Service estimates that if no action is taken to contain the 
woodwasp, it could spread across the entire southern pine region in under 55 years and 
generate damage of US$ 2-11 billio n in impacts to softwood production.  
IAS affecting aquatic infras tructure and fisheries  
Several highly invasive aquatic organisms have reached Europe and/or spread within Europe 
through common pathways (e.g. shipping and aqu aculture) and associated vectors (ballast 
water, fouling, imports of diseases and pathoge ns). Economic impacts ma y relate directly to 
fisheries and aquaculture production and equipm ent and/or have indirect impacts on water-
related infrastructure e.g. on hydropow er generation and pipe systems. 
Dreissena polymorpha  (zebra mussel).  Control techniques focus on ballast water 
management and measures for prevention of sp read. Costs for control and damage are not 
available specifically for Europe. However, US figures assessed cumulative costs to US and European industrial plants (1989-2000) at US  $750 million to US$ 1 b illion (National Aquatic 
Nuisances Clearinghouse, 2000). In the Great La kes region (US/Canada), damage for the 
period 2000-2010 has been assessed at US$ 3.1 billion (intake pipes, water filtration 
equipment, power plants), US $100 million/year (lost power generation based on a one to two 
day downtime and a 1% reduction in plant he at rate) and $5 billion (potential economic 
impact). 
 
Mnemiopsis leidyi  (Sea walnut, comb jelly) . Control costs not known but estimated impacts 
on Black Sea fishing nations of 24.53 million €/year, mainly generated by loss of the commercial anchovy catch. Biofou ling of fishing equipment by Cercopagis pengoi  (Fish-
hook waterflea)  in the Primorsk (Koivisto) area led to economic losses at one fish farm of 
0.03 million €/year in 1996-1998.  
Some cost/benefit figures for IAS control in fi sheries are available for the Great Lakes region 
(US/Canada). Benef its of controlling Petromyzon marinus (Sea Lamprey) , which preys on 
commercially important fish, are assessed in th e range of $2-4 billion/year. If ongoing control 
was terminated, lost fishing opportunities and indirect are estimated at $500 million/year. 
Cost of sterile male release in Lake Hu ron is US$ 300,000 and cost of one lampricide 
treatment in St Mary's River is $4.2 million. For Gymnocephalus cernuus  (Ruffe) , estimated 
total cost of control programme over 11 y ears is US$12 million. Estimated losses for the 
native fishery were estimated at US$ 0.5 million/year in 2001 and for sport fisheries in Lake Erie, at US$ 60 million/year between 1985-1995. 
Balanus improvisus  (Bay barnacle, Acorn barnacle) . In Sweden, estimated maintenance 
costs to defoul pleasure boat s estimated to 123-334 million SEK/year. One shipping company, 
the Broström Group, estimates the cost for an ti-fouling treatment per tanker ship of 11,000 
GRT (Gross Register Tonnage) to be around 400,000-500,000 SEK every 30 months (i.e. 
160,000-200,000 SEK/year. The Swedish Shipowners A ssociation estimates the costs for very 
large vessels (>40,000) to be around 250,000-500,000 SEK/year. 
EN 66   EN Where one pathway provides opportunities for mu ltiple species introductions, prevention may 
involve construction of specific infrastructure to reduce known risk of unwanted introductions 
(e.g. a salinity barrier in the Suez Canal to pr event Lessepsian migrati on of non-native aquatic 
species via the Suez Canal to the Mediterranean). In the US, the cost of constructing an 
enhanced barrier (electrical fish barrier) to keep the invasive Asian carp out of the Great 
Lakes is US$9.1 million. In 2002, the U.S. Army Corps of Engineers co nstructed a temporary 
electronic dispersal barrier on the Chicago San itary and Ship Canal at a cost of approximately 
$2.2 million. 
IAS that threaten animal and human health 
Growing risks are associated with IAS as vector s of disease that affect wild and/or farmed 
animals and in some cases, humans. IAS may al so directly impact on human health where the 
organism or a part thereof is t oxic or provokes allergic reactions.  
Cervus nippon  (Sika deer) : invasive in at least 9 European countries and a documented 
vector of diseases affecting both wild and farmed animals.  UK estimated control costs 0.82 
million €/year. 
Aedes albopictus  (Asian tiger mosquito) . In Italy (Emilia Romagna), costs related to health 
risk prevention, eradication and co mmunication total 1.10 million €/year. 
Thaumetopoea processionea  (Oak processionary moth) . In the UK, measures to prevent 
human health impacts estimated 0.36 milli on €/year. The Royal Botanic Gardens Kew 
estimates it will spend £20,000-30,000 in 2008 to control the pest. The future financial implications could be extremely high due  to both health costs and oak damage. 
Invasive plants affecting human health include common ragweed ( Ambrosia artemisifolia ) 
(health costs in Germany estimated 32.10 million €/year; associated hay fever costs also 
known to be high in seriously infested regi ons like the Rhone valle y (France), Hungary, 
Croatia and northern Italy). For Heracleum mantegazzianum  (Giant hogweed) , control costs 
are available for at least four EU Member States:  
Czech Republic, control/containment costs 0.01 million €/year;  
Germany, total estimated control costs 12.30 milli on €/year (medical 1.05, roadside clearance 
measures 2.34, human health 7.70, nature conservation 1.20);  
Estonia, 5-year strategy for nationwide contro l of alien Heracleum species launched in 2005. 
Estimated control costs (2005) for 235 hectar es are 1.4 million Est onian krooni/year (~90.000 
€) and in 2006, 3.36 million Estonian  krooni (~240.000 €) for 300 hectares; 
in Sweden, the Swedish Road Administration controls giant hogweed along roads in three 
regions. Cost to the Mälardal en roads authority of weed control at five sites is 28,000 
SEK/year at an average cost of 100 SEK/m
2. Costs to the Stockholm road authority range 
between 100,000-200,000 SEK/year (180,000 SEK in  2006, approximately 130,000 SEK in 
2007). 
Institutional and operational costs of IAS prevention and control  
Operational costs of policies to support IA S prevention and control include improved 
governance and coordination, strengthened capacitie s for border control, risk analysis, early 
EN 67   EN warning and rapid response, and improved info rmation systems, research and training (see 
section 3 above). 
Some Member States are investing in deve lopment of national IAS strategies, improved 
baseline information and targeted manage ment and research. Work is ongoing under the 
Technical Support contract to iden tify indicative costs for these operations as they relate to 
the natural environment, incl uding by reference to non-EU ju risdictions. Figures so far 
identified for EU Member States are as follows: 
in Denmark, the 2008 state budget has earmarked  a specific sum for IAS (2 million Danish 
kroner) for the first time; 
in the UK, the Environment Agency spends £1. 5 million per annum on st aff and project costs 
for controlling invasi ve non-native species42; 
in Germany, the Federal State of Schleswig Holste in put a ca. 3 million Euro tender out to co-
fund a programme to develop an effici ent ballast water treatment system. 
                                                 
42 Defra (2003) in Parliamentary Office of Science and Technology note (April 2008, Number 303) 
(http://www.parliament.uk/documents/upload)