Hours into a journey to Portugal from Morocco, the crew of a 46-foot sailing cruiser noticed something was wrong with the rudder. Then, someone shouted what they saw slicing through the choppy waves: “Orcas! Orcas!” The orcas kept pace with the boat, slamming into its side and chewing at the rudder, according to its skipper, a photographer onboard and video of the encounter. For about an hour, the crew signaled their predicament to the Spanish Coast Guard and tried to stay calm. “There was nothing we could do,” said Stephen Bidwell, the photographer, who was two days into a weeklong sailing course with his partner when the ramming began. “You’re in awe at the same time as you are nervous.” The skipper, Gregory Blackburn, said he wrestled for control of the boat as the orcas banged into it, interfering with the rudder. “It’s a reminder of where we are in the food chain and the natural world,” he said.

Eventually the boat managed to motor back to Tangier, Morocco. But marine scientists took note of the episode, on May 2, and said it continued a puzzling pattern of behavior by a small group of orcas off the Iberian Peninsula’s western coast. The orcas, according to the researchers, have caused three boats to sink since last summer and disrupted the trips of dozens of others. Wild orcas, although apex predators that hunt sharks and whales, are not generally considered dangerous to humans. The animals, the largest of the dolphin family, have been known to touch, bump and follow boats, but ramming them is unusual, marine scientists say. A small group of orcas, numbering about 15, started to batter boats around Spain in 2020, with researchers calling the behavior uncommon and its motivations unclear.

“Every week there is an incident,” said Bruno Díaz López, a biologist and the director of the Bottlenose Dolphin Research Institute who was not involved in last year’s research. “We really don’t know the reason.” In the most recent example, orcas battered a sailboat off the coast of Spain, causing it to sink in the early hours of May 5. The Spanish authorities quickly arrived, and the four people onboard were rescued “in good humor,” said Christoph Winterhalter, the president of the Swiss company that was operating the boat, Hoz Hochseezentrum International. The University of Aveiro biologist, Dr. López Fernandez, said that it was possible that the three boats sank over the past year because they were vulnerable to leaks or not equipped to endure the damage. (“The condition of the boat was very good,” Mr. Winterhalter said of the one his company had chartered.)

The small group of orcas, including only two adults, were responsible for a majority of the interactions with boats, which number some 200 a year and range from the North African coast to France, according to Dr. López Fernandez. Researchers do not know what is behind the behavior. Some have speculated that it is an “aversive behavior” that could have started after an incident between an animal and a boat, like an entanglement in fishing line, or an invented behavior from young orcas that is being repeated.

sig230 wrote: Fri May 26, 2023 10:36 am They are pissed off and won't take it anymore!