Which animal is scientifically documented to follow bizarre cultural fads, like wearing dead salmon as hats?

How a salmon became an orca trend

The animal behind the unlikely “salmon hat” fad is the orca, also called the killer whale. In a documented episode, an orca carried a dead salmon balanced on its head, and other whales began doing the same. The behavior spread through the group and later faded. Researchers cannot ask the whales what the salmon meant to them, so the precise motive remains unknown; the striking point is that the behavior appeared to pass from one whale to others.

What makes a fad cultural

A behavior counts as cultural when it is learned socially and shared within a community, rather than arising only from instinct or from each animal independently encountering the same conditions. Orcas are well suited to this kind of learning. They live in close-knit family groups, and young whales spend years alongside relatives, observing how they communicate and find food.

That social learning can produce group-specific habits, including distinctive calls and hunting techniques. A salmon perched on a head is a much less practical-looking example, but it illustrates the same basic possibility: one whale’s unusual action can become something others imitate. The “hat” is memorable not because scientists know why the whales wore it, but because the behavior spread socially—and then disappeared.