Fastest marine mammal

- Who
- Unknown
- What
- 55.5 kilometre(s) per hour
- When
- 12 October 1958
On 12 October 1958 a bull killer whale (Orcinus orca) an estimated 6.1-7.6 m (20-25 ft) long was timed at 55.5 km/h (34.5 mph) in the northeastern Pacific. Similar speeds have also been reported for Dall's porpoise (Phocoenoides dalli) in short bursts.
Orcas are "apex predators", ie they have no natural predators