Invasive alien species

Invasive alien species are plants or animals that are introduced by man, accidentally or intentionally, outside of their natural geographic range into an area where they are not naturally present. They are often introduced as a result of the globalisation of economies, for instance by trade via ships, shipment of wood products infested with insects, or the transport of ornamental plants that then establish themselves into the wild and spread. The EU is developing policies to actively deal with the problem of alien species.
Water hyacinth - Eichhornia crassipes

Invasive alien species (IAS) can have very severe effects on new environments. Many alien species become invasive, competing against or preying on native species, which can lead to their extinction and eventual ecological devastation.

Alien species may lack natural predators in their new environment, allowing them to breed quickly and spread without limits to eventually take over a natural area. They can transport disease, out-compete native species, alter the food chain, decrease biodiversity, and even change ecosystems by altering soil composition or creating habitats that encourage wildfires.

The EU experiences annual damages worth EUR 12 billion as a result of IAS effects on human health, damaged infrastructure, and agricultural losses.

In Europe, there are over 12,000 alien species, 15% of which are invasive. IAS are the third most severe threat to European threatened species. According to a recent report, 354 threatened species (229 animals, 124 plants and 1 fungus) are specifically affected by IAS (which accounts for 19% of all threatened species in Europe).

In 2013, the European Commission put forward a proposal for legislation in the form of an EU Regulation on IAS, focusing on the prevention of their entry, early warning/rapid response, and effective and coordinated management. The Regulation entered into force on 1 January 2015 which focuses on a subset of IAS of EU concern and requires national governments to work together to detect those IAS of high concern and coordinate management measures. Member States are also requested to identify the most relevant pathways of entry of IAS, and to establish action plans to address them.

IUCN, through a service contract with the European Commission (EC), provides technical and scientific support for the implementation of the Regulation. You can find more information about the technical reports IUCN has produced for the EC here.

The IUCN’s Species Survival Commission organises the Invasive Species Specialist Group, which is a global network of science and policy experts. The Group aims to reduce threats to natural systems and native species by increasing the awareness of IAS and examining ways to prevent, control or eradicate them.

Go to top