• The European otter is a semi-aquatic mammal that has long been hunted in France.
  • Classified as a protected species, the otter also benefits from national action plans.
  • Fragile, exposed to the dangers of road traffic, it is also penalized by a low reproduction rate.

Its friendly boil would almost make you forget that it has long been hunted for its coat and its erroneous reputation as a pest. To the point of practically disappearing from French territory during the 1980s. Forty years later, the European otter, whose world day is celebrated this Wednesday, is making a remarkable comeback in a large number of French departments. This semi-aquatic mammal has managed to significantly repopulate the regions where it had escaped extermination (Massif Central, Brittany, Pays-de-la-Loire, part of Nouvelle-Aquitaine). And even to reconquer new basins, like Occitania, Normandy, the Pyrenees or the Rhone Valley.

"This is excellent news because, like any carnivore, it plays an important role in the ecosystem," says Meggane Ramos, European otter specialist at Groupe mammalogique breton. "She's come a long way. It should be remembered that it was once present throughout the France, except in Corsica, before becoming rare. In some countries, it has completely disappeared," says Cécile Kauffmann, coordinator of the national action plan for otters for the French Society for the Study and Protection of Mammals (SFEPM).

Low reproduction rate

It took a protected species classification in 1981, followed by two national action plans (2010-2015, 2019-2028), to achieve a "slow recovery of populations". Slow, because the otter remains a fragile animal, "very vulnerable to the degradation of its habitats", and suffers from handicaps for its offspring. "She has a low birth rate. Sexual maturity is not reached until about 3 years of age and will only give birth to one to three young. And then its life expectancy in nature hardly exceeds 4 to 5 years," says Meggane Ramos.

If the population count seems "impossible" because of the great discretion of the animal, the otter is followed by a network of naturalists thanks to its footprints, droppings (called spikes) and some food remains. "We also use camera or video traps. It is a meticulous, uncertain, but essential research work," says Meggane Ramos. An approach that today makes it possible to authenticate its presence in many wetlands, including rivers with urbanized banks, such as the Loire. However, the Grand Est and Hauts-de-France rivers seem to be exceptions. "There have been attempts to reintroduce it in Alsace but it has not really worked," says Cécile Kauffmann.

Damage to fish farms

A relatively solitary animal (unlike its cousin the sea otter), the European otter evolves on a pool 5 to 20 km long in search of fish, crayfish or amphibians. "We often think that the otter is a testament to good water quality, but in fact it mostly goes where it finds fish and shelter," says Ramos. Its presence has been detected in areas where the water is of very average quality, such as the Gouëssant in the Côtes-d'Armor. His gluttony encourages him, from time to time, to enter fish farms, especially trout. To the chagrin of fish farmers, the damage can be significant. "We have a facilitator who raises awareness among professionals and provides them with technical assistance. When the facilities are well protected, there is no problem," reports the facilitator of the national otter plan.

Although it has no predators in the wild, the main threat to the European otter remains human activities, especially road traffic. "There are structures, roadblocks, which force him to cross roads, collisions can then occur, laments Cécile Kauffmann. Fortunately, there are more and more specific facilities designed for it, such as benches under bridges. They participate in the recolonization of the otter. Some trapping aimed at coypu, invasive rodents with which the otter is often confused, are still sometimes fatal, as well as dog bites. "Overall, she is doing better and better but it is too early to think of her definitively safe. It still deserves our vigilance," insists Cécile Kauffmann.

  • Planet
  • Animals
  • Loire
  • Auvergne-Rhône-Alpes
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  • Threatened species
  • Brittany
  • Pays de la Loire