Tahlequah, the mother orca known as J35, carrying her dead calf for 17 days and more than 1,000 miles, is once again demonstrating a similar act of grief.
Her most recent calf, a female known as J61 to researchers, was first spotted on December 20 in the Puget Sound area, on the northwest coast of Washington state, by citizens. The National Oceanic and Atmospheric Administration confirmed the sighting on Dec. 23, according to Michael Weiss, director of investigations at the Whale Research Center. Tragically, on New Year’s Eve, the calf was confirmed dead, he said.
Researchers reported, as of Jan. 5, that Tahlequah is still carrying the calf, said Brad Hanson, a wildlife biologist at NOAA’s Northwest Fisheries Science Center. Updates on the mother’s activity with J61 may become limited as her family group, or pride, departs the main Puget Sound base.
Tahlequah is constantly pushing the dead calf’s body, which weighs about 300 pounds, with her snout to keep it close and prevent the ocean from washing away the carcass.
“Like last time, I think it’s enough to recognize how strong the mother-calf connection is in killer whales (among the strongest social relationships of any animal) and see that she’s clearly not ready to let go,” Weiss explained. , whose doctoral research focused on the social structure of orcas, via email.
The loss of a calf is not only devastating for Tahlequah, but for the rapidly declining population of Southern Resident killer whales, which is on the brink of extinction, with only 73 of the marine mammals remaining as of 2019.
The Southern Resident killer whale population is considered “one of the most endangered marine mammal populations” in the United States, according to researchers.
Deep mourning of an orca mother
Some female orcas are known to carry their dead calves, but the length of time and distance Tahlequah carried her two dead calves is unusual, experts say. Candice Emmons/NOAA Fisheries
This act of mourning raises concerns among investigators, including Weiss and Hanson, for its physical and emotional impact on Tahlequah as a member of the highly vulnerable southern resident population. Carrying the extra weight of the baby’s body is putting a strain on the mother and slowing her movements, which can affect her ability to forage for food.
However, Weiss noted that during the previous 17 days of the orca’s mourning, there had been no visible decline in her condition, which could indicate that other members of her pod were helping her receive food.
Although some female orcas are known to grieve the loss of their young in a similar way to Tahlequah, the distance and time she carried her newborn in 2018 made her an exception. His current behavior, which reflects his past actions, is also unusual, according to Weiss.
Tahlequah is known to be the mother of another orca, J47, who is now around 14 years old, as well as J57, a baby born two years after her loss in 2018.
Killer whales typically breed every five years, giving the mother time to recover from the physical demands of pregnancy and birth, Hanson said.
While there is no significant data to suggest why Tahlequah may have lost two calves during her lifetime, killer whale pregnancies are full of challenges. About 70% of pregnancies in the Southern Resident killer whale population, to which Tahlequah and her offspring belong, result in miscarriages or very early deaths, Weiss said.
Challenges Facing Southern Resident Orcas
Failed pregnancies and struggles for survival in the exclusively piscivorous orca communities of the northeast Pacific Ocean can be attributed to challenges caused by pollutants, noise, inbreeding and a lack of Chinook salmon, which is their main food source, according to Weiss.
The loss of a female offspring like J61 is particularly damaging to the future of the species because it reduces the population’s ability to reproduce.
“Assuming (orcas) live full lives, we’re counting on them producing five to six offspring under ideal conditions, and part of the problem is that most females in this population haven’t produced that many viable offspring,” Hanson said.
