Collisions with merchant ships are the main threat to the fin whale, the largest whale in the Mediterranean, which during the spring comes to feed on the Garraf coast, between the ports of Barcelona and Tarragonawhere the high maritime traffic endangers these cetaceans.
This has been documented by a study by the EDMAKTUB association published by the magazine ‘Frontiers’, in which it has been estimated that April is the month in which there are more collisions between whales and ships.
During the spring months the presence of cetaceans on the Catalan coast is abundant and, according to EDMAKTUB, this year, with bad weather conditions at the beginning, has generated a good oceanographic and trophic situation, which has increased the number of whales feeding off the Catalan coast, where some thirty specimens have already been sighted.
Most of the whales sighted off the Garraf coast are fin whales (Balaenoptera physalus) which, at 24 meters in length, are the largest whales that regularly transit the Mediterranean. Also called the fin whale, the fin whale is a little-known animal, according to the association, which this year is carrying out its eighth campaign of the Fin whale project, with daily trips to sight and collect samples during the months of March, April and May.
The study of the association has concluded the “high risk of collision between whales and merchant ships on the Garraf coast”, especially in “the area of the Foix submarine canyon and the area between this canyon and the Cunit submarine canyon -Cubelles”, where they have documented with exemplary photographs of whales with marks of collisions with boats, some accidents that “show the seriousness of the situation”. Among the specimens sighted there are two with serious injuries that have affected their spine after colliding with ships.
The study warns that “feeding behavior, especially surface feeding, significantly increases the risk of collision due to its erratic behavior near the surface, with many accelerations and changes of direction.” “The boats usually pass through the area at a speed of between 10 and 20 knots and it is very easy not to detect the whale or to detect it when it is already too late,” says the work.
In order to reduce this risk, the association has urged measures to be taken and has proposed reducing the speed in feeding areas in the spring season, making schemes for the separation of maritime traffic in the ports of Barcelona and Tarragona to modify certain routes so that they pass further away from the main feeding areas, and to have the presence of marine mammal observers on board who can help detect these animals.
This year the association has begun testing a thermal camera to study the feasibility of installing them on ships to automatically detect the presence of cetaceans. According to those responsible for EDMAKTUB, the 2022 season is being “especially positive”, with a high number of whales feeding off the Catalan coast, and since the campaign began a month ago they have already sighted thirty different specimens, of which more than half had already been sighted and identified in previous years.