Author: Erika Lau
The latest IUCN Red List update shows that the Pyrenean desman (Galemys pyrenaicus) has been pushed to a higher threat category. Newly listed as Endangered, the species is experiencing continuous range contractions across its geographic distribution.
The desman is restricted to Andorra, northern and central Spain, northern Portugal, and French Pyrenees. In Spain, the species has been observed to contract its range in the Central System. Recent range declines of more than 50% and 60% have also been documented in Northern Portugal and in the French Pyrenees, respectively.
This decline is driven by a combination of factors. The species prefer fast-flowing, mountainous rivers that are threatened by ongoing anthropogenic activities, including construction of hydroelectric plants, dams and reservoirs, which besides altering the river habitat also cause the isolation of river networks, in turn fragmenting desman populations, water pollution, water extraction for agriculture, and public works on river banks. Additional threats to the species include invasive species, such as the North American mink (Neovison vison) and the red swamp (Procambarus clarkii) and the signal (Pacifastacus leniusculus) crayfish, climate change, and secondarily direct persecution from fisherman.
These observed range contractions and the persisting threats call for an increased need for conservation. Habitat restoration and appropriate management of watercourses, along with improved knowledge of the species, have been proposed as important conservation actions. In particular, the removal of dams and other fluvial barriers to free-up rivers is expected to be highly beneficial to the species. Action plans have been developed for France and Portugal, although they require an update. Furthermore, LIFE projects have also been dedicated to the species in France and Spain but are being required in Portugal. Research on the potential negative impacts of invasive species should also be undertaken.
Photos: Lorenzo Quaglietta
Lorenzo is the SMSG’s newest member. Welcome to the team Lorenzo!