German Federal Agency for Nature Conservation (BfN)


Invasiveness risk assessment

Nature conservation risk assessment methodology for invasive alien species

Invasiveness risk assessment serves to protect native biodiversity from alien species

Species which are not naturally native to a given area, but are instead intentionally or unintentionally introduced by humans can pose a threat to biological diversity and are thus deemed invasive. Since 2011, the Federal Agency for Nature Conservation (BfN) has used a set of criteria to assess the invasiveness of alien species.

Protecting biological diversity is a central aim of both European and international agreements. The occurrence of species outside their natural distribution area due to human activities such as trade and transportation is seen as an important cause of biodiversity loss worldwide.

The invasiveness of alien species, meaning their potential threat to native nature and species diversity, can vary significantly. To combat and eradicate alien species efficiently and effectively, each species must be assessed for the threat it poses. The Federal Agency for Nature Conservation in cooperation with the Austrian Environment Agency has thus developed a methodology which enables to assess the invasiveness of alien species from a nature conservation risk perspective.

Criteria-based system allows classification of alien species into three invasiveness categories

The chosen approach is based on a transparent, criteria-based system which makes classification verifiable and replicable. The evaluation leads to classification in three different invasiveness categories: 'invasive, threat confirmed', 'potentially invasive, threat assumed' and 'not currently invasive, no known threat'. Based on current distribution of the species concerned, the categories allow to draw conclusions regarding the action needed and the priorities that must be set. The success of any action taken is, however, reliant on the availability of promising nature conservation methods and measures.

Between five and ten percent of alien species threaten biodiversity

Since 2010, the Federal Agency for Nature Conservation (BfN) assesses the invasiveness of all alien species in Germany. The findings show that most alien species do not pose a nature conservation problem. However, some five to 10 percent of alien species do pose a threat to biodiversity in Germany and are thus classed as invasive. Particularly in the case of newly occurring invasive species or those which occur in very small areas, there is a chance that, with relatively little effort, the threat posed to biodiversity can be combated through complete eradication.

More information

Invasive Alien Species (Convention on Biological Diversity)

Invasive Alien Species (European Commision)