Tag Archives: whale fathers

Orca Whale Fathers – They Often Raise Each Other’s Offspring

K26 travels tight with new sibling K42 on the west side of San Juan Island, July 6, 2008 (Photo by Holly Fernbach)
Young males from three pods traveling together: L78, J27 and K26 (Photo by Ken Balcomb)

Killer whales are polygamous and as far as is known the males do not have any known defined role to play in raising the calves they produce.
Instead, the adult males stay with their own mothers and help care for their siblings, nieces and nephews, who were sired by a different male. Similarly, their own calves are raised in a different maternal group, and any males in that family will help with raising the calves sired by the other males.
By all accounts, mating is a free-for-all between different pods, yet it is extremely rare for two members of the same family to mate together. Periodically the different pods hang out together, and occasionally all three of the southern resident pods – J,K,and L – meet in what the researchers call a “super pod”. Vigorous interaction and mating can occur at these gatherings, but apparently the females only select males from outside of their own family group.

Young male J26 (Photo by Katie Jones)

It all sounds like a pretty sweet deal for the males – and it is, but it is a sweet deal for the whole clan, and may be key to why the orcas coexist so peacefully. In this situation, male rivalry could be minimized, plus they would seem to have a vested interest in insuring the well being of all calves since most likely they don’t know which ones they might have fathered.

J1, known for his wavy dorsal fin. Photo by Emma Foster (CWR)
L73, also wavy. (Photo by Dave Ellifrit)

Although the males in the Southern Resident orcas aren’t known to mate within their birth families, they must wind up breeding with their own progeny at some point when the females who might have been their own calves  in other pods mature. According to the Center for Research, the population shows the expected low genetic diversity that would result. Yet the lack of diversity appears to be true throughout the orcas’ range, even among populations that are robust.
To account for this, scientists speculate that the orca’s low genetic diversity might be the result of having gone through a genetic “bottleneck” about 130,000 years ago, during which time their population was drastically reduced.
However indirectly, the dads play a key role in ensuring the success of the whole southern resident clan of orcas. And although they are deemed apex predators and appear to have no natural enemies, what that really means is that there are no known successful natural predators. Doubtless the males are active and vigilant in protecting their families from harm – an orca calf would be vulnerable to large sharks, for instance – and ultimately whether they rear other males’ offspring or their own, what matters is that all the babies spend their lives in a family “cocoon”.
In the big picture, it works beautifully.

L41 traveling north through Haro Strait, August 10, 2008 (Photo by Dave Ellifrit)

From: January 2008 II-124 NMFS
” Resident killer whales display some of the most advanced social behavior of any nonhuman mammal, as evidenced by their highly stable social groupings, complex vocalization patterns, the presence of long-lived post-reproductive females, and behaviors such as cooperative foraging, food sharing, alloparental care, matriarchal leadership, and innovative learning. Maintenance of minimal group sizes is therefore probably necessary in preserving beneficial social interactions and in raising young.”