Invasive Alien Species in freshwater and marine environments
Invasive Alien Species (IAS) are animals, plants, fungi or other microorganisms that, introduced accidentally or intentionally in a different environment than their natural one, can bear serious consequences for the new environment (you can find several episodes of our Podcasts dedicated to this topic by clicking on the tag Invasive Alien Species).
Besides the negative impacts of IAS on biodiversity, ecosystem services, food security and human well-being, there is also a huge cost related to the management of these biological invasions. In addition to that, biodiversity conservation actions are often constrained by a lack of alignment between governance frameworks and the ecological reality, that operates regardless of political boundaries.
This aspect is addressed in a Policy Brief recently published by GuardIAS, a Horizon Europe project launched in 2025 that focuses on the growing threat of IAS in freshwater and marine environments.
Key points of the brief are the fragmentation of current EU invasive species policy, the inconsistencies occurring when scientific evidence and risk assessment are translated into decisions, and the barriers posed by socioeconomic drivers, trade pathways, and implementation gaps to existing regulations.
In parallel, the project team has also developed a Policy Brief on the role of biofouling, the gradual colonisation of an artificial hard substrate by a wide range of organisms, that end up developing complex three-dimensional communities. Beyond the negative impacts on operability, functionality and security of the affected systems, biofouling also carries biosecurity risks related to the introduction and spread of IAS (for example, when these organisms colonise a ship’s hull and are transported to different areas).
The authors conclude the briefs with a set of suggested solutions; if you are curious about them, find the full documents here:
- Biofouling as a Vector for Marine Invasive Alien Species (Phillip J. Haubrock et al.)
- Beyond Borders: Aligning Conservation Policy and Ecological Reality (Mar Santos-Simón et al.)
In the image: a Lionfish (genus Pterois). The Lionfish is one of the 11 invasive species Case Studies of GuardIAS. Picture source: Wai Siew on Unsplash.