Hanson, who was able to observe her behaviour from a boat on Wednesday, said J35 was draping the dead calf across her snout or on top of her head, and that she appeared to dive for it when it sank from the surface. He said the calf was only alive for a “handful of days”.
“I think it’s fair to say that she is grieving or mourning,” Joe Gaydos, science director of SeaDoc at the University of California, Davis, said of J35. Similar behaviour can also be seen in other socially cohesive animals with relatively long life spans, such as primates and dolphins, he added.
Calf mortality is high: Only about one in five orca pregnancies result in a calf that lives to its first birthday, according to the Center for Whale Research. The centre’s research director, Michael Weiss, estimated that only 50 per cent of orca calves survive their first year.
The centre described the death of J35’s calf as particularly devastating – not only because she could have eventually grown to give birth and bolster the struggling population, but because J35 has now lost two out of four documented calves.
The population of southern resident killer whales – three pods of fish-eating orcas that frequent the waters between Washington state and British Columbia – has struggled for decades, with only 73 remaining. They must contend with a dearth of their preferred prey, Chinook salmon, as well as pollution and vessel noise, which hinders their hunting. Researchers have warned they are on the brink of extinction.
Other southern resident orcas have been observed carrying dead calves, Weiss said, “but certainly not for as long as J35 carried her calf in 2018.”
There was some good news for the J pod, however: Another new calf, J62, was observed alive by officials and scientists.
Southern resident orcas are endangered, and distinct from other killer whales because they eat salmon rather than marine mammals. Individual whales are identified by unique markings or variations in their fin shapes, and each whale is given a number and name.
Travelling together in matrilineal groups, the orcas at times can be seen breaching around Puget Sound, even against the backdrop of the downtown Seattle skyline.
