Rare desman is on edge of extinction
Researchers say they have never seen a young desman
One of France’s most mysterious and secretive mammals, the Pyrenean desman, is in danger of dying out as numbers have fallen by 30% in 10 years.
Only 20-25cm long and with more than half of that their tail, the rat trompette with its distinctive 3cm elongated snout is little studied but scientists say the species is undergoing decline across its full range.
Researchers from the Life+ unit at the Conservatoire d’espaces naturels de Midi-Pyrénées say its natural habitat is fast-flowing mountain streams but it faces threats from water pollution, obstructions such as dams, water extraction and attacks by otter and mink.
Nocturnal and secretive, the Galemys pyrenaicus is a cousin of the mole. It is found in the Pyrénées up to 2,700m high and is rarely spotted, seeming to spend most of its time in the water, coming out only to eat, groom and to sleep.
Researchers say they have never seen a young desman so have no knowledge of reproduction, other habits or even an accurate estimate of numbers. Some captured desmans have been freed with tiny trackers on their backs to find out more.
It does not eat fish, hunting instead for larvae and crustaceans using its whisker-covered snout to sense and manipulate prey, like a mini version of an elephant’s trunk.
The European IUCN ‘red list’ of at-risk species rates it as ‘vulnerable’ and the conservatoire researchers say it is disappearing at a faster rate in the west of the Pyrénées than in the east.
Work is being done on the Aston river in Ariège to see if scientists can help. About 130 tonnes of granite have been used to stabilise banks and give shelter and for exit ramps in ditches and other canalised watercourses to give an escape route.
Part of the project has also seen ‘nesting boxes’ sited on an access canal to the river and these have cameras fitted in case desmans start to use them.
See tinyurl.com/y87o6fkn for more information in English.
