Male Orcas Are Mama’s Boys

Photo: David Ellifrit Centre for Whale Research

He may be a 20-foot long, 13,000 lb. killing machine, but he’s also a
mama’s boy! Scientists have discovered that male killer whales are coddled
by their moms well into adulthood:

“Females have a really unique life history,” said Emma
Foster, a marine biologist at Exeter University in England. “They
stop reproducing in their 30s and 40s, but they can live into their

Using 36 years of data on orcas in the Pacific Northwest, the researchers
found that for males over 30, the death of a mother meant an eightfold
increase in the likelihood of death within a year.

Killer whales stick with their mothers their entire lives. Dr. Foster
suspects that mothers help sons with foraging or offer protection in
encounters with other males. Among female orcas over 30, there was only
about a threefold increase in the likelihood of death in the year after
a mother’s death. “It makes more sense for the mothers to
invest more in their sons, because there is no increased burden on the
family group,” Dr. Foster said. “Children of sons move on
to new family groups.”