The only colony of otters that lives in the waters of the Mediterranean Sea moves in Cap de Creus and nearby bays, and its population is increasing, according to the technicians who monitor this species. A few days ago it was possible to capture, for the first time, the image of a specimen coming out of the water on one of the beaches in the Cap de Creus area.
The Mediterranean Sea basin is home to other groups of otters located on half a dozen islands in its eastern zone (Corfu, Lesbos...): but they are specimens that move in fresh waters (streams or wetlands), while the colony of Cap de Creus is the only one where “they are at sea every day; that is to say, they do not enter occasionally, but live in the sea”, explains Jordi Ruiz-Olmo, a fauna technician from the Department of Climate Action.
The otters of the Empordà enter streams and torrents, but eat in the sea; They sleep on land and the next day, "without eating anything, they enter the water again," adds Ruiz-Olmo.
These animals are more common on the coasts of Scotland, Ireland, Norway, Brittany or Galicia. In any case, they always need to be close to rivers or aiguamolls with fresh water, since they have to clean their fur to remove the salt, otherwise it would deteriorate, they would lose their insulating capacity and they would be forced to spend excessive energy. For them, their fur is like their neoprene suit that they should always keep spotless.
On the Costa Brava, its population has increased since the fishermen first saw it a few years ago, and now it is made up of about ten or twelve specimens: three breeding females, who usually have two offspring on average, and at least one or two males. “Otters need good water to clean themselves; and that they have it here is a good indicator”, says Alfred Encuentra, PhD in Biology and environmental consultant.
In Catalonia, in recent years, the otter (Lutra lutra) has experienced an evident recovery in a large part of the river basins. The progressive reduction of contamination and the end of direct persecution, added to its great dispersal capacity, have led to a rapid reoccupation of the territory. The last census (2016) shows a good state of conservation (it is not an endangered species). But it is not an abundant population, since they are territorial animals, with a density of one specimen for every 20 kilometers of river, adds Encuentra.
The colonization of the waters of the Costa Brava is the consequence of the successful colonization process in the Catalan rivers, where vital space has been gained (by finding suitable habitats, with food and shelter, even in the Llobregat, the Tordera or the Besòs) until reach the sea, where they have found an ideal place.
On the Costa Brava it moves in a territory that includes Cap de Creus and the adjacent bays of Roses and Port de la Seva, so that it embraces a territory that goes from Montgrí to Portbou.
The otter was in decline in Catalonia and on the verge of extinction, since it reached a minimum population around 1987 (with two residual groups in the Nogueras Ribagorçana and Pallaresa). However, its reintroduction in the eighties in the Fluvià and the Muga has resulted in great success, as a result of improving the quality of the river water. "We need to see them more in the Ebro delta," says Alfred Encuentra.
To continue deepening its study, this year the follow-ups will be extended. Tours will be carried out on foot and by boat, their traces will be collected and camera traps will be installed at strategic points to estimate the number of family groups, their diet and their customs.
