Adult male killer whales are the world’s biggest mama’s boys. Literally.
Matriarchs strongly protect their adult sons, keep them free from agonistic interactions with other groups or individuals, and make sure that they get enough food.
Although they also provide help to their adult daughters as well, the vast majority of killer whale effort goes to their sons.
Maternal food-sharing with their daughters declines when the daughters reach sexual maturity and begin to have their own calves, but the provisioning of sons goes on to their old age.
In fact, an adult orca male over the age of thirty experiences a 13.9-fold increase in his mortality risk in the year following his mother’s death. This is a massive number and indicates the clear importance of the provisioning of adult orca males by their moms.
Females experience an increased mortality risk as well (a 5.4-fold increase), so although there is disparity between the amount of help allocated to sons and daughters, there is no denying that killer whale matriarchs provide help to their adult children.
This post is an adapted excerpt from my book “Wild Moms: Motherhood in the Animal Kingdom“