Suggested operational objective: Ecological restoration builds on IAS management activities to reinstate functioning ecosystems dominated by native species.
5.5.1 Background and general approach
Restoration is an integral part of managing IAS. Although IAS removal is sometimes a goal in itself, it should also be seen as an important element in achieving other environmental targets such as recovery of endangered species or repair of ecosystem function.
Many restoration efforts have succeeded in mitigating negative IAS impacts with important benefits. However, they may have also unforeseen consequences that exacerbate rather than mitigate the original IAS problem. For example:
• invasions can cause long-lasting changes to the ecosystem that persist well after the removal of the IAS;
• ‘secondary invasions’ involve the rapid replacement of the removed species by others that capitalise on the disturbance caused by the control operations and/or the resource alteration caused by the IAS;
• IAS management can degrade ecosystems and negatively affect indigenous species;
• where alien species invade by infiltrating ecosystem networks (e.g. pollination and dispersal networks, food webs), their removal can cause trophic collapses;
• restoration efforts can be compromised by conflicts of interest, an example being IAS that provide habitat or food for endangered native species.
These examples highlight the need to consider all implications of planned control and restoration programmes.
Well-designed restoration of IAS-damaged sites can reduce their vulnerability to future invasion and may strengthen ecosystem resilience to other environmental stresses to avoid ecosystems being pushed beyond certain thresholds or tipping points.275 Restoration may include release or stocking of native specimens, e.g. native crayfish in alien-free rivers or river catchments. Restoration programmes can also secure broader socio-economic benefits where they contribute to the maintenance and enhancement of ecosystem functions and services. They may also strengthen public acceptance and understanding of necessary control measures.
Even when technically feasible, restoration can be potentially very expensive and needs
275 Third edition of the Global Biodiversity Outlook: implications for the future implementation of the Convention on Biological Diversity.
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continuous supervision, assistance and monitoring of developments. It is usually executed locally as a by-product of eradication or control actions, rather than as an overarching target at national or regional scale. Generic elements for effective programme design should therefore include:
• incorporating prevention objectives into relevant sector policies e.g. primary production, land and water management, spatial planning;
• defining the situations in which MS may be required or encouraged to carry out restoration;
• defining the state to which restoration should be carried out, taking account of feasibility and an appropriate timescale;
• providing guidance if restoration includes the release of specimens;
• establishing responsibilities for restoration actions.
Actions taken under the EU IAS Strategy will be nested under the Post-2010 Strategy which will provide for explicit restoration targets for the first time. The Council has recognised the importance of setting a clear baseline outlining the criteria against which achievements are to be assessed, while taking into account that in some cases, restoration may also consist of natural regeneration.276
5.5.2 Approach to restoration for EU protected species and natural habitats
Ecological restoration as a general policy objective is embodied in the nature Directives.
Under the CBD, Parties are encouraged to consider the role of IAS management as a cost-effective tool for the restoration and maintenance of protected areas and the ecosystem services they provide.
For Natura 2000 sites, the restoration objectives could be based on the requirement to attain favourable conservation status for species and habitats as defined in the habitats Directive. The current status of species and habitats, as assessed by recent reporting under the Directive, could serve as a benchmark (COM 2010). Ongoing monitoring activities under Article 11 of the Directive may contribute to detecting any positive or negative trend in FCS.
The reintroduction of native species, following the control/eradication of IAS which represent a threat to them, may be envisaged provided that such programmes are fully consistent with international guidance.277 Such a reintroduction would not only justify the removal of the alien species but can also facilitate gaining support of the public opinion.
However, this should not be confused with assisted colonisation (i.e. translocating and releasing species beyond their current range limits as part of a climate change adaptation strategy).
276 Council Conclusions 2010 §4.
277 IUCN Guidelines for Re-Introductions http://www.lcie.org/Docs/LCIE%20IUCN/IUCN%20Reintroduction%20guidelines.pdf
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The LIFE+ Regulation already provides a basis for co-financing IAS ecological restoration projects. Allocation of funding to date has been ad hoc rather than geared to broader strategic objectives. Consistent with the Strategy, MS should maximise opportunities to secure co-benefits at the site- and broader ecosystem level through restoration projects.
Examples:
In Ireland, the LIFE Shannon Regional Fisheries Board project for Restoration of the Lower Shannon SAC for lamprey, Atlantic salmon and European otter includes an objective to ‘stop and reverse the damage caused by invasive exotics Giant hogweed and Japanese knotweed, restore the natural riparian zone and develop a management programme to ensure re-colonisation does not occur after completion of the project.’278
In Austria, the LIFE-Nature project for Protection and Maintenance of Pannonic Steppes and Dry Grasslands included measures to reduce black locust (Robinia pseudacacia) and Tree-of-Heaven (Ailanthus altissima), both invading nutrient-poor dry grasslands in eastern Austria, and thereby restore natural plant and animal species communities.279
5.5.3 Approach to restoration for European waters and marine regions
At the ecosystem level, the WFD and MSFD provide a policy framework through which restoration objectives may be set and measured through common indicators, monitoring and assessment. However, linked to the particular difficulties associated with eradication and control in aquatic environments, prevention should always be the overriding goal.
For the WFD, restoration needs to be addressed as an integral part of national measures to achieve or maintain good ecological status for European inland, transitional and coastal waters by 2015 and prevent their further deterioration. However, as noted (3.2.6), there is currently no common approach to using alien species data in classifying ecological status which makes it difficult to develop a regionally or subregionally consistent approach or to define restoration objectives at the river basin level.
Restoration actions could also be tailored to the Flood Risk Management Directive linked to the WFD. This prioritises soft non-structural measures that use natural processes to the maximum to reduce flood risks. IAS restoration could specifically focus on riparian zones and wetlands to address riverbank erosion and restore wetland retention capacity.
Responsibilities for restoration, and associated cost recovery, should be defined where appropriate in accordance with the environmental liability Directive (see 5.6.6).
Under the MSFD, measures to maintain or achieve good environmental status should also include restoration measures where feasible. Proposed biopollution indicators currently under consideration could provide a tool to develop an appropriate target tailored to marine biogeographic regions (ECOSTAT 2009).
278 Source: NOBANIS Newsletter No.3/2010.
279 http://www.steppe.at/downloads/Kurzbericht_STEPPE_E.pdf
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5.5.4 Approach to restoration in the wider landscape
The CBD supports actions to address non-climatic stressors, including IAS, within the broader context of climate change adaptation. It links these to increased efforts for restoration of ecosystems and habitats, including connectivity as appropriate.
As noted, implementing measures to enhance / restore ‘green infrastructure’ might open up the landscape for IAS dispersal and therefore involve trade-offs (see 5.2.4). Once again this strengthens the case for prevention. However, integrated restoration programmes based on the ecosystem/regional landscape approach280 can increase resilience to invasion and support targeted monitoring of areas most at risk from possible dispersal. The Commission could support this through exchange of best practices to deliver co-benefits for conservation and climate change adaptation (COM 2010, Council Conclusions 2010).
Lastly, the EAFRD includes an agri-environment measure on protection and promotion of local animal breeds and local plants to preserve them and preserve traditional genetic resources. MS could use this measure to support restoration in the wider agricultural environment by promoting actions based on existing/traditional and native species. These existing instruments should be taken into account as achieving the economic results (yields, resilience) with European/local species.
280 In South Africa, extensive experience on combined programmes for IAS control/biome restoration and restoration of key ecosystem services has been gained through the Working for Water/Wetlands/Fire/Energy programmes centred on invasive plant clearance and watershed rehabilitation (see http://www.dwaf.gov.za/wfw/ ).
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