For generations, humans in New South Wales, Australia had an unusual hunting partner. Orcas and humans worked side by side, and both benefited from the collaboration. Sadly, new analysis reveals that this curious population of orcas is now extinct.
The law of tongue
This was a unique partnership: apex land predators working with apex sea predators toward a shared goal. Orcas would herd large baleen whales toward the shore and then signal to whalers in the coastal town of Eden by slapping their tails on the water. The whalers would then spear the giant cetaceans, taking the meat but leaving the orcas their cuts of choice: the tongues and lips. This was dubbed “the law of tongue.”
Two orcas in shallow water. Photo: Shutterstock
Isabelle Reeves, who led the new study, thinks the relationship between people and orcas may have existed for thousands of years.
Co-author Steven Holmes is a descendant of the Thaua people, members of the Yuin nation in eastern Australia. Holmes explained the importance of the relationship to his ancestors.
“They considered the killer whales their brothers,” he told The Conversation. “When a Thaua died, they believed they would be reincarnated as killer whales. That way, the Thaua always remained one mob, whether whale or man.”
Some whalers sang to encourage the orcas. One orca, which whalers named Old Tom, joined hunts for 30 years.
“My people had a long-lasting friendship with the beowa [orcas] in Eden, especially Old Tom…[They] would swim with Old Tom, holding on to his dorsal fin. My ancestors were never hurt or injured.”
Old Tom’s body is now in Eden’s museum.
When did the practice stop?
Even after the region was colonized, Europeans tried to continue the whaling practice, hiring skilled Thaua to help them.
But the last record of commercial whaling in Eden is from 1928. Baleen whale populations decreased, and orcas disappeared from the area. Why they left is debated. Some suggest there was no longer enough food for them, some that the relationship was ruined when European settlers commercialized the practice. Others believe that someone broke the law of tongues.
Researchers have been investigating whether the ancestors of the Eden population of orcas still exist. Orcas live in quite distinct groups, and these groups show different behaviors and even use different dialects. These differences help when trying to study a specific group. And in this case, Old Tom’s skeleton was key.
Thaua people and orcas hunted together for generations. Photo: Eden Killer Whale Museum
Using Tom’s teeth, the research team was able to study the genetics of the group. Drilling into the teeth, they created a powder to sequence his genome. As a final step, they compared this to global data.
Though there was some genetic similarity with a common ancestor of orcas in Australasia, the North Atlantic, and the North Pacific, they could find no clear descendants.
Tongues still in fashion
Tongues are still a delicacy for orcas. But typically, they target baleen whale calves. Baleen whales are so big that taking an adult down without human help is incredibly difficult. What surprises most people is that even in the wild, orcas will often leave the rest of the whale after stripping out their favorite cuts.
From baleen whales, such as humpbacks, orcas will only eat the tongue, from sharks they may only eat the liver, and from a dugong, they will go for the intestines. In the Pacific Northwest, some orcas will harass and kill porpoises and then not eat anything.
An orca breaching in Canada. Photo: Shutterstock
Orca behavior is closely studied. Last summer, orcas made headlines for attacking boats, then two went on a shark killing spree, and another adopted a motherless pilot whale calf.
Some of the new behavior seems increasingly aggressive, for example, sinking boats and grouping together to drown blue whales. So, is something up with the planet’s orcas?
“These are animals with an incredibly complex and highly evolved brain. They’ve got parts of their brain that are associated with memory and emotion that are significantly more developed than even in the human brain,” orca expert Deborah Giles told Live Science.
With this in mind, there are two general ideas about what is happening. The first theory is that they are adapting to their ever-changing environment and teaching each other to survive. As a result, group intelligence is increasing. If this theory is accurate, humans are a major driver of this change. Our shipping lanes, fishing habits, and reshaping of the environment are forcing orcas to alter their habits.
The second theory is less dramatic, arguing that these are not new behaviors, but have not been witnessed previously.
