Nutrias, large rodents originally introduced to Europe by fur farmers but now considered an invasive species, have become the latest point of contention in Slovenia over wildlife management.

Following the row over the culling of bears, a petition has now been started in an attempt to stop the authorities' plan to remove nutrias from the Ljubljana Marshes.

Preparations for the complete removal of the fast growing population of the species from the landscape park have been under way since September when the Agriculture Ministry gave the go-ahead for the measure.

However, a petition urging a stop to the nutria kill and applying sterilisation as an alternative measure has been signed by more than 19,000 people in a matter of days.

Among those opposing the measure is Tina Gaber, the life companion of Prime Minister Robert Golob. She has appealed for support for the petition on her Instagram profile, posting a video of her petting nutrias.

Threat to ecosystems

Janez Kastelic, director of the Ljubljana Marshes Landscape Park, says the nutria is an invasive species whose population has spread to the point of threatening ecosystems and indigenous species of animals and plants.

The exact size of the population in Slovenia is not known, but it has doubled or even trebled in the past decade and the species is invading ever new areas.

Most specimens can be found in the river basins of the Ljubljanica and the Rižana in the Slovenian Istria, but they are also increasingly spotted along the Sava and Mura rivers.

Data from the Slovenian Hunting Association shows that 715 nutrias were removed from the wild last year, up from 570 in 2021 and 532 in 2020.

However, Kastelic has told the STA that regular trapping alone is no longer a sufficient method to control the nutria population, nor is sterilisation.

Guidance taken from EU

The Agriculture Ministry has merely approved the trapping of the animals by means of live traps. The subsequent steps will follow the EU manual for the management of vertebrate invasive alien species, which takes into account animal welfare.

"Sterilisation or castration is not included in the EU manual as a measure to control nutria population, which means that we picked the most practical method, that is trapping and killing," says Kastelic.

He expects the trapping will be launched in about a month, exclusively in the area covered by the landscape park, that is in the municipalities of Ig, Vrhnika and Brezovica.

Five hunting clubs are to take part in the project, which will take several years. Considering the size of the population, they expect to trap 20 nutrias per day. They could then be used to feed other animals.

Trust the experts

Commenting on the opposition, Kastelic says such reactions are to be expected and that it is right to hear all the arguments.

"It is important to bear in mind though that invasive alien species are outcompeting native ecosystem species, and if society believes the process should be left to the natural dynamics, it should also accept that certain species will disappear," he said.

Ljubljana Mayor Zoran Janković has appealed to the public to trust the experts with the issue just like the municipal authorities have done. He also urged the public not to feed nutrias or other wild animals.

Nutrias have also caused damage to the municipality, damaging the floating houses in the Gruber Canal which are owned by the city.