While whales are known to grieve the loss of their loved ones, the recent story of an orca mom clinging to her dead calf for over two weeks demonstrates unprecedented evidence of the strength of the species’ familial bonds. The heart-wrenching saga began on July 24, 2018, after a female calf born to J35, aka Tahlequah — a member of the endangered Southern Residents Killer Whales (SRKW) pod — died 30 minutes after birth. Instead of letting the carcass sink into the ocean, the grieving mother began carrying the lifeless body by balancing it on her forehead or nudging it along the water surface with her nose.
Over the next few weeks the scientists at San Juan Island's Whale Museum in Washington, who had witnessed the tragic event unfold, noticed that Tahlequah was often assisted by other members of the pod in her quest to keep the baby afloat. The “mourning” excursion, which captivated the world and had experts fretting about Tahlequah’s health, lasted for 17 days. The ordeal finally ended on August 13, when the 20-year-old mammal was seen chasing a school of salmon with her pod mates in the Haro Strait without the dead calf in tow. "Her tour of grief is now over, and her behavior is remarkably frisky," the Center for Whale Research said. It added: "The carcass has probably sunk to the bottom of these inland marine waters of the Salish Sea [between Canada and the US], and researchers may not get a chance to examine it for necropsy (autopsy of an animal)."
Though orcas are believed to have stronger family bonds than other whale species due to their larger pod sizes, scientists have never seen a pod grieve for so long. Peter Ross, a killer whale expert and vice president of research at conservation group Ocean Wise, says, “This is unusual behavior. “It’s not normal. We haven’t seen it before. What it means — who knows?” Dennis Christen, senior director of zoological operations at the Georgia Aquarium, agrees with Ross and says that while this kind of mourning has been previously observed for short periods of time, staying with a dead calf for 17 days is unusual.
Tahlequah is not the only member of the SRKW pod that has researchers concerned. Since the beginning of August, scientists have been trying to save three-year-old orca J-50, who has lost 20 percent of her weight and appears to be starving. While the scientists initially attributed her emancipated and lethargic appearance to the lack of food, an analysis of fecal samples obtained from the ocean indicates that her condition might be exacerbated by a parasite known as Contracaecum. NOAA says while the worm is not a problem in healthy animals, in weaker animals, it is known to penetrate the stomach lining and cause a bacterial infection in the bloodstream or bore into internal organs. The scientists, who have been trying to heal J-50 by feeding her and administering antibiotics through a dart, plan to add a dewormer to the next treatment. They hope it will reduce the infection and restore her health.
The plight of the tight-knit, chirping pod of 75 SRKW that reside in the Salish Sea — a saltwater trough stretching from the south of Seattle to the eastern coast of Vancouver Island — is not new. Human pollution and over-fishing has sharply reduced the mammals’ prime food source, the Chinook salmon, leaving the killer whales starving. Over the past 20 years, the pod has lost 72 members and added only 40 calves. Experts worry that if something is not done to reverse the situation soon, we may lose the precious animals altogether.
Resources: CNN.com, Seattletimes.com,westcoastfisheries.noaa.org, npr.org.