“They always seem to go for the rudder, and I think that’s because it’s a mobile part of the vessel,” Ruth explains. The media coverage became stranger - and a little darker - when the scientists also revealed that Gladis white had quite a severe injury on his head: a gash that appeared to have been caused by a boat, possibly by a propeller. The scientists published their conclusions about the identity of the culprits, and immediately there were news reports of the “rogue pod” and the marauding “teenagers”. So far, the researchers have not worked out which family “the three Gladises” belong to. Males though will wander off, mixing and mating among other pods. Killer whales live, hunt and move in very closely connected family pods: tightly knit, matriarch-led groups that - in some populations - have even been shown to have their own pod-specific dialects.įamilies generally stick closely together, with long-lived grandmothers helping to raise young and to teach youngsters to hunt. This photo and video line-up showed that three individuals were involved in most of the incidents: juvenile males named in the official orca record as black Gladis, white Gladis and grey Gladis.
#Orca whale Patch#
Orcas each have a uniquely shaped pale grey saddle patch behind their dorsal fin, which from the surface serves as a killer whale “fingerprint”. They compared footage of the incidents to a catalogue of images captured and used by CIRCE to identify the animals. In September, the researchers started gathering evidence. “It’s getting worse and worse,” says Dr Renaud de Stephanis, another biologist involved in the investigation. A killer whale broke the surface at the side of the boat and he says that for 45 minutes, the animals bashed and chewed at the rudder, spinning the boat around. In September, a man sailing his boat home to Scotland from Spain suddenly had the wheel spun out of his hands. A video of that incident showed the crew trying to outrun the animals, which appeared to pursue the boat. Later that same day, a Spanish naval yacht, Mirfak, lost part of its rudder after an encounter with orcas. In August, a French-flagged vessel radioed the coastguard to say it was “under attack” from killer whales. In July, a sailing vessel had to be towed back to shore after a group of orcas repeatedly hit and damaged its rudder. “But touching them and causing damage? I just thought people were scared and were misinterpreting what was happening.” “These killer whales are always curious around boats, they will approach them,” she tells me. Ruth now works at the Madeira Whale Museum, but she studied this population of orcas for six years - they were the subject of her PhD. “I just didn’t believe it at all at first,” says Dr Ruth Esteban, a softly spoken marine scientist who chooses her words carefully, not keen to speculate about something as multi-faceted and complex as orca behaviour. But the ongoing conservation crisis does not explain why some of them suddenly started to behave so bizarrely and apparently aggressively around boats. This specific population of orcas is listed as critically endangered and protected by law. And, as the bluefin gradually recovered, so did the killer whales. In 2010, international regulators slashed the annual catch that was permitted in the Mediterranean Sea.
Some 60 killer whales live in these waters today, that dipped to just 39 back in 2011, a decline that the Spanish conservation organisation CIRCE found was driven by a crash in bluefin tuna stocks. Humans’ relationship with these orcas though has been on a knife-edge ever since we started fishing for more of that highly prized and highly priced bluefin tuna than appears to have been sustainable. At one point, one of the larger animals came right to the stern and flipped onto its back – you could see its bright white underside.” But while I was on the phone I could hear them ramming the boat.
Be as “uninteresting” as possible, they said. With their VHF radio out of range, they had to use the satellite phone to contact the coastguard, who advised them to switch off the motor and take down the sails. The boat was 20 miles (32.2km) off Porto, at least three hours from the Portuguese coast. “They were right at the back of the boat.”Ī sense of curiosity and excitement very quickly turned to fear when one orca disappeared beneath the boat and there was a loud thumping sound from the hull. The only other encounter he had had with an orca was more than 20 years ago in a Vancouver aquarium, but he was in no doubt that he was looking at a group of killer whales. “He said: ‘It looks like we have some large dolphins,’” recalls David. An hour before sunset, one of the crew called out.
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