Adaptions
- Killer whales are among the fastest swimming marine mammals. They can swim at speeds of up to 28 mph, but probably only for a few seconds at a time. Killer whales usually cruise at much slower speeds, less than 13 kph (8 mph). They can cruise slowly for long periods of time.
- Killer whales are agile in the water. When swimming near the surface, a killer whale usually stays below water for 30 seconds or less.
- Although not generally deep divers, foraging killer whales can dive to at least 100 m (328 ft.) or more. The deepest dive known for a killer whale was performed under experimental conditions and was 274.3 m (900 ft.).
- In the eastern North Pacific, resident killer whales usually make three or four 15-second dives and then a dive that lasts about 3–4 minutes, repeating this pattern.
- A killer whale breathes through a single blowhole on top of its head. The blowhole is relaxed in a closed position. To open the blowhole, a killer whale contracts the muscular flap covering the blowhole. A whale holds its breath below water. A killer whale opens its blowhole and begins to exhale just before reaching the surface of the water. At the surface, the whale quickly inhales and closes the muscular flap.
- Like all mammals, killer whales are warm-blooded. A killer whale’s core body temperature is about 36.4º to 38ºC (97.5º–100.4ºF)—close to that of a human. Living in the sea poses a particular challenge to marine mammals, because water conducts heat about 27 times faster than same-temperature air.