A Mother’s Bond: “Mourning” Behavior in Killer Whales
Pictured above is female Alaskan resident killer whale AX76 and her presumed first calf. If it is a female, she will stick by AX76 for most of her life; she may eventually break off and form her own group when she begins have calves of her own, but will always be nearby her own mother. If it is a male, this little calf will never stray far from his mom, even when he is a fully grown bull. In short, the bonds between a mother killer whale and her offspring are some of the strongest in the animal kingdom.
So what if the worst happens? What if this calf dies before it has a chance to grow up?
It is very difficult, if not impossible, to know what an animal thinks and feels. We must be careful when ascribing emotions to other species; sometimes we project our own human emotions onto animals even when it’s not necessarily accurate.
While we can never be absolutely sure what fellow pod members are feeling when a killer whale calf dies prematurely, there is definitely something going on.
L72 Racer carrying her dead newborn. Photo by Robin Baird of Cascadia Research.
Epimeletic behavior refers to the behavior of an adult cetacean that is aiding a distressed, injured, or dead individual, sometimes carrying it around at the surface, protecting it, or attempting to save it in some way. This type of behavior is seen in several species of cetaceans, including killer whales.
Often, the mother of a recently deceased calf is seen pushing the dead infant’s body around at the surface. This can last for hours or even days on end. Researchers believe in these cases, it is very likely that these are grief or mourning behaviors. Epimeletic behaviors may initially be the mother’s attempt to rescue her calf, (i.e holding it at the surface to breathe). However, even after the calf is long dead, mothers still stay with their babies.
Grief behaviors do not appear to provide any benefit to the animal grieving; indeed, these behaviors likely have high costs to the individual. The strong social bonds that killer whales have to their offspring and relatives are probably the main causes for such behavior, which is notably lacking in other marine mammal species, such as pinnipeds.
A female killer whale from New Zealand pushing her dead calf with her melon; this mother stayed with the calf for two days. Photo by Orca Research Trust.
The grief a mother feels may continue long after the body of her dead infant is removed. While not a killer whale, there is one case of a captive beluga that showed us this mourning process. After a failed pregnancy, a dead calf was removed from the body of a female beluga and taken out of the pool. The mother, with no calf in sight, resorted to pushing around her own placenta. The placenta was eventually removed as well, and the grieving mother carried around a buoy for several months.
It is hard to look at this types of behaviors and see anything but a grieving, mourning mother. We know from studies of their brain structure that killer whales are highly emotional creatures that likely experience a wide range of feelings. It is not such a stretch to say that they likely feel sorrow (or, perhaps something similar) when a family member dies.
I made this post several months ago and given recent events, though it would be appropriate to update it.
J35 “Tahlequah,” a female killer whale from the endangered southern resident population, has given the most heartbreaking and steadfast example of epimeletic behavior observed in cetaceans to date.
Photo: Micheal Weiss/Center for Whale Research
She gave birth to a female calf on July 24th; tragically, the newborn only survived for 30 minutes before passing away. Since then, J35 has carried her infants body everywhere she goes. For 16 days she has held her baby’s body and travelled hundreds of miles in the process. This is an extreme example of epimeletic behavior and it may be the longest documented case of a female cetacean carrying a dead calf.
This story has captured peoples’ hearts all around the globe. We feel her grief as if it was our own. People are writing poems, creating paintings, and holding prayers for Tahlequah as she continues her “tour of grief.” Most importantly, Tahlequah has drawn attention to the endangered southern residents’ plight like never before. Her population is starving and is down to 75 individuals due to a lack of chinook salmon; public outcry triggered by her mourning is making a difference. The government is paying attention and is listening.
To help restore salmon populations and save the southern residents, please call Washington Governor Jay Inslee and urge him to support breaching the Snake River Dams: 360-902-4111.