First actions launched to control the American mink.

With the support of the Tarragona Provincial Council, and within the framework of the newly established Biodiversity Monitoring and Alert Network for the American Mink, several measures have been undertaken to control the American mink’s spread in the Tarragona region.

The Network launches in the Tarragona region

The American Mink Biodiversity Monitoring and Alert Network, created at the beginning of 2025, is a citizen science initiative implemented in the regions of Tarragona and Terres de l'Ebre, which has the involvement of several volunteers, the organizations GEPEC, GEVEN, Graëllsia, Grupo de Natura Freixe, La Sinia and managers of protected natural areas such as the Montsant Natural Park and the Poblet National Area of Natural Interest.

In this first phase, each participant has installed one or more camera traps at strategic locations across the territory, such as wetlands or rivers in the Tarragona region. The data collected from the various photo-trapping stations are now being analyzed to identify the detected species and assess their distribution.

Preliminary analyses of the American mink indicate that in 2025, this species occupies the Gaia and Francolí basins, but it has not been detected in the Ebre basin nor in its tributaries, the Siurana and the Canaleta.

From monitoring to the first captures of American mink

A second line of work, initiated after confirming the presence of the American mink, has focused on monitoring and capturing them in two areas: Les Madrigueres (El Vendrell) and the upper Gaia basin.

In Les Madrigueres, potential American mink tracks were detected in the beach area, and the GEVEN reported predation on Kentish plover (Charadrius alexandrinus) nests. Based on these signs, floating platforms with clay were installed to capture footprints and confirm the mink’s presence. However, in the following weeks, no new traces were found, suggesting that the mink0s presence in the area is temporary or transitory, with no sedentary individuals detected.

The situation is different from the Gaia River basin, where the establishment of American mink populations has been confirmed. In the upper Gaia River basin, Bioscicat expanded the American mink control efforts already being carried out by la Sinia organization, targeting undersampled areas. Several floating platforms with traps were installed, resulting in the capture of 14 American minks.

Placement of floating platforms equipped with footprint traps to detect American mink.

The current limits of American mink's distribution

Currently, the known distribution of the American mink in Catalonia is limited to the Gaia and Francolí basins. The Francolí represents the southernmost known extent of the species in Catalonia, and the distance from permanent rivers in the Segre basin supports the hypothesis that the Gaia basin acts as a corridor for the species’ spread into the Francolí. The high densities recorded by the American mink in the Gaia and Francolí over recent years demonstrate the species’ significant colonization potential towards the southernmost basins, including the Ebre.

These findings highlight the urgency and scale of the problem, enhance our understanding of the species, and underscore the need to redesign the Strategy for the control and eradication of the American mink in Catalonia to improve the management of this invasive species while safeguarding the region’s biodiversity.

Awareness of invasive species

The case of the American mink highlights a broader challenge: the need to raise awareness about invasive alien species. All of them share a common origin linked to human activity, whether through international trade, tourism, hunting and sport fishing, the deliberate release of pets, or the fur industry. In Catalonia, there are already several examples, such as the apple snail in the Ebre Delta, the Asian hornet or the red swamp crayfish. Each of these species affects biodiversity, ecosystems and even public health to varying degrees.

The American mink poses a threat to endangered species in the counties of Tarragona, such as the Iberian water shrew (Neomys anomalus), the white-clawed crayfish (Austropotamobius pallipes), and the water vole (Arvicola sapidus). For the latter, the arrival of the mink is likely the cause of some of the local extinctions recorded in Catalonia. It also represents a threat to ground-nesting bird species in coastal wetlands, such as the bird colonies of the Ebre Delta. In this context, the fight against the American mink in the counties of Tarragona forms part of the broader global effort to preserve biodiversity in the face of invasive species threats

Funding and support

This project has been made possible thanks to the support and funding of the Tarragona Provincial Council, within the framework of subsidies for non-profit organizations dedicated to environmental protection and improvement projects, with a grant amount of €22,000.