Finland to introduce prison sentences of up to three years for spreading invasive species

Finland is set to impose stricter penalties, including potential prison sentences, for the deliberate spread of invasive species, as a new unwanted arrival—the Argentine flatworm—threatens the country’s ecosystems, reports Yle.

The flatworm, a predatory species that feeds on earthworms and other soil-dwelling invertebrates critical to soil health, has already been detected twice this year in plant shipments from Belgium. First identified in Finland last year, the species has raised concerns among authorities due to its rapid spread across Europe, previously recorded in Germany (2008) and Sweden (2022).

Under upcoming revisions to Finland’s criminal code—driven by an EU environmental crime directive—the intentional release of invasive species could soon carry a maximum three-year prison term, provided the act causes significant environmental harm. Karin Cederlöf, a legislative counsellor at the Ministry of Agriculture and Forestry, cited examples such as releasing non-native fish into waterways or freeing captive wolf hybrids, both of which could devastate native ecosystems.

“Once these species establish themselves, eradication becomes nearly impossible,” Cederlöf warned. The EU has mandated member states to implement the directive by the end of May, though Finland’s legislative process, led by the Ministry of Justice, remains ongoing.

### Climate change accelerates the threat
Finland’s national list of invasive species now includes 134 entries, with 114 designated by the EU. Warmer temperatures linked to climate change are further aiding their spread, allowing non-native species to establish themselves farther north. Erja Huusela, a senior researcher at the Natural Resources Institute Finland (Luke), urged vigilance, particularly among commercial nurseries, where the flatworm can hide in root balls and soil.

“It’s often active only at dusk, making detection difficult,” Huusela noted. She advised consumers to inspect plants carefully and report suspected sightings. Proper disposal of garden waste also plays a key role in preventing unintentional spread.

The Argentine flatworm, a slimy, finger-length predator, poses a direct threat to soil biodiversity. Authorities emphasize that early detection and strict biosecurity measures are critical to mitigating its impact—before legal consequences come into force.