Objective I: Plant diversity is well understood, documented and recognized
Objective II: Plant diversity is urgently and effectively conserved
Objective III: Plant diversity is used in a sustainable and equitable manner
Objective IV: Education and awareness about plant diversity, its role in sustainable livelihoods and importance to all life on earth is promoted
Objective V: The capacities and public engagement necessary to implement the Strategy have been developed
Invasive alien species (IAS) are species whose introduction and/or spread outside their natural past or present distribution threatens biological diversity.
IAS occur in all taxonomic groups, including animals, plants, fungi and microorganisms, and can affect all types of ecosystems. While only a small percentage of organisms transported to new environments become invasive, the negative impacts can be extensive and over time, these additions become substantial.
Invasive species have been shown by the Millennium Ecosystem Assessment to be a major agent of ecosystem degradation as they affect not only plants and plant populations, but they are detrimental to vital plant associations and habitats, reducing ecosystem services and values to people.
Invasive species also pose a significant threat to global economic health with estimated costs of US$350 billion annually.
Most developed countries have controls on the introduction of potentially invasive species and procedures for risk assessment of intentional introductions, especially those with government agencies devoted to biosecurity. This is less true in many developing countries where awareness of the threat of invasive species is more limited and the capacity to prevent and manage invasions is often inadequate.
Climate change is predicted to enhance the spread and impact of many existing invasive species, as well as potentially providing suitable conditions for presently non-invasive species to become invasive.
The removal of invasive alien species is a key management activity for effective conservation. However experience has shown that preventing new invasions of harmful species is more cost-effective than waiting until they have become a threat. Applying preventative measures requires action at both international and national levels including the coordination of agencies working in the areas of plant health, transport, trade, tourism, protected areas, wildlife management and water supply.
Download an introduction to Target 10 here.
Alien species that become invasive are considered to be a main direct driver of biodiversity loss across the globe. In addition, alien species have been estimated to cost our economies hundreds of billions of dollars each year.
A species introduction is usually vectored by human transportation and trade. If a species’ new habitat is similar enough to its native range, it may survive and reproduce. For a species to become invasive, it must successfully out-compete native organisms, spread through its new environment, increase in population density and harm ecosystems in its introduced range.
Common characteristics of IAS include rapid reproduction and growth, high dispersal ability, phenotypic plasticity (ability to adapt physiologically to new conditions), and ability to survive on various food types and in a wide range of environmental conditions. A good predictor of invasiveness is whether a species has successfully or unsuccessfully invaded elsewhere.
Invasive alien species can be particularly problematic for islands. The geographic isolation of islands limits immigration of new species, allowing established species to evolve with few strong competitors and predators. Islands therefore have a high proportion of endemic and specialized flora and fauna. They are more prone to invasion by alien species because of the lack of natural competitors and predators. In addition, islands often have ecological niches that have not been filled because of the distance from colonizing populations, also increasing the probability of successful invasions.
Implementation of this target contributes to Target 9 of the Aichi targets of the Strategic Plan for Biodiversity 2011-2020:
T9: By 2020, invasive alien species and pathways are identified and prioritized, priority species are controlled or eradicated, and measures are in place to manage pathways to prevent their introduction and establishment.
This target addresses biological invasion as a phenomenon, and does not just focus on the invasive species themselves.
It combines both the prevention of invasion by alien species (animal, plant, micro-organism) and the management of ecosystems and habitats into which they have already been introduced.
Land management plans (especially for areas designated as important for plant diversity - see target 5) need to be designed (using the ecosystem approach) to address the damage done to plant species and /or their communities and to restore ecosystem functions, goods and services.
The Conference of the Parties (COP) to the Convention on Biological Diversity (CBD) has recognized that there is an urgent need to address the impact of invasive alien species (IAS), and established IAS as a cross-cutting issue at its fourth meeting. The decision of COP 6 included adoption of Guiding Principles for the Prevention, Introduction and Mitigation of Impacts of Alien Species that Threaten Ecosystems, Habitats or Species.
There is a need to build capacity for the development and enhancement of early warning, early detection and biosecurity/biosafety systems for invasive species, including in collaboration with the International Plant Protection Convention and regional and national phytosanitary services.
There is also a need to recognise that it is economically sound to invest in prevention and early detection and removal where possible, instead of having to deal with control and eradication of invasives.
Please also check in the database of Tools of Resources for Case Studies relevant to this target.
"Here today, here tomorrow? Horizon scanning for invasive non-native plants" is a report from Plantlife which provides details of a Rapid Risk Assessment screening process developed to identify potentially invasive non-native plants in the UK.Download
Invasive alien species (IAS) are a global issue that requires international cooperation and actions. Preventing international movement of IAS and rapid detection at borders are less costly than control and eradication. Preventing the entry of IAS is carried out through inspections of international shipments, customs checks and proper quarantine regulations. Prevention requires collaboration among governments, economic sectors and non-governmental and international organizations.
An International Sentinel Plant Network has been proposed by botanic gardens to provide an Early Warning System, building on New Zealand's 'Expat Plants' project.
Please contact us if you have any questions, comments and suggestions related to this target.