Spain wants ships to slow down and watch out for whales while passing through the Strait of Gibraltar, one of the world’s busiest maritime routes.
The recommendation drew praise Saturday from environmentalists who had sought the measure for years to prevent collisions with whales.
Fast ferries, especially, can be a threat to endangered sperm whales, which come to the strait from the Mediterranean to feed between February and July.
The whales “do not know what is going on around them,” said Katharina Heyer, president of the Foundation for Information and Research on Marine Mammals, an environmental group based in the Spanish town of Tarifa, which overlooks the strait.
The Spanish navy’s recommendation this month urged ships to go no faster than 15 mph and sail “in a maximum state of vigilance” to avoid colliding with the whales.
Sailing speeds in the strait separating Europe from Africa vary greatly, but high-speed ferries can reach nearly 35 mph.
It is “the first time in the Mediterranean, and probably in Europe, a measure of this kind has been taken,” said Renaud de Stephanis, a marine biologist with the Center for Conservation, Information and Research on Cetaceans in southern Spain.
During the feeding season, the strait is home to 20-30 sperm whales, which are about 60 feet long, said de Stephanis. Year round, there is a population of about 300 smaller pilot whales.