National Geographic : 2005 Apr
Fins and frolicking can give indications about orca well-being. Dorsal fins of orcas under stress may flop over, like that of an Alaska male (above), which is thought to have endured a diffi cult winter in ill health. While most orcas, such as those passing whale-watchers near Vancouver (right), are indifferent to humans, calves often seem to show off. A juvenile named Auriga (below) breaches playfully near Seward, Alaska.