Although it’s unlikely you’ll ever see an orca or Killer Whale in the wild, they are very much present here off the coast of Southern Africa.
Orca’s really are amazing ocean mammals- they can live up to 90 years of age and they have complex social and familial structures. Within these structures, grandparents play an active, and very valuable role.
A recent study found that Orca calves, have a much better chance of survival in the wild if their grandmothers are around and involved. The study also showed that Orca grannies are involved with the rearing of calves for a large portion of their lives, with some grandmothers still actively involved up to the age of 90 years. If a mother Orca is out on the hunt, the granny automatically assumes the role of the primary caregiver to ensure the calf is safe from predators, and to ensure the calf is fed. It is not surprising that this vastly increases the survival rates of young Orcas. On the inverse, if a grandmother dies prematurely, the survival rate of the calf is dramatically reduced with its chances of dying quadrupling.
There are not many mammals on earth, who love beyond reproductive age, and if they do nature normally has a way of getting rid of them. Orcas, along with humans, will live past their fertile years and even go through menopause resulting in the females of the family, and their offspring, staying together as a unit for many years. Rather than being alienated because she adds no value in terms of her ability to procreate, a grandmother becomes very valuable in the structure of the family, and even more so as she gets older. This is how her role ensures her genetic legacy is passed on.
With human threat, which is resulting in the loss of many ocean mammals, findings like this are greatly valuable and enable us to understand what the species needs in order to proliferate in the wild.