Blue whale

Balaenoptera musculus

LENGTH 20–25 m / 65–83 ft

DORSAL FIN Variable shape; very small relative to body

APPEARANCE Blue-grey, mottled colouring; dorsal fin not seen until well after blow ends

BEHAVIOUR Blows 9 m / 30 ft tall; often exposes tail flukes when diving

Photos by A. Phillips, C. McMillan, J. Towers, J. Ford. Illustrations by A. Denbigh, not to scale.