Why Do Orcas Kill in Captivity, Not in the Wild?

A new book called “Death at Sea World” explains some of the mysteries behind the wrongly-named mammals known as killer whales, and I found some sympathy for these leviathans of the deep when I read a review in the WSJ by Jonathan V. Last. For instance, male orcas spend 75% of their lifetimes close to their mothers. Even when they’re grown, they’re still hangin’ within a body length with ma.

The creatures are members of the dolphin family and despite the fact that no killer whale has ever been reported to have killed a human in the wild, their record at Sea World is pretty bad. They don’t even fight with other killer whales in the wild, yet in captivity they’ve been known to go at each other with those gigantic teeth.

The book explains how orcas live in matrilineal groups–lead by mama, her calves and her juvenile young and they form a pod. Marine biologist Naomi Rose said that orcas have a babysitting system where mothers often leave dependent calves with adult siblings, aunts or uncles for an hour or two to give the adults can forage, socialize or just rest.

The first serious injury by a captive orca happened in 1971, when a park employee was mauled and needed 200 stitches to close her wounds. Dozens of injuries have followed. One orca in particular has been the instigator in more than one incident–Tilikum is his name. Sea World bought him despite the fact that he had killed a trainer just eight months earlier. But the company needed the big male because tightening laws were making in-house breeding necessary.

In 1999, a man stowed away in the park and may have jumped into the pool. Chomp. Gone. Why do these beasts kill only in captivity? Some of the unproven theories are that they’re just too large to be kept in captivity. Others think that it’s their highly intelligent brains that lead them to rebel against their captors.