Sperm whales (Physeter macrocephalus) raise their huge strong flukes in a deep sounding dive reaching depths of 3 km for up to 2 hours. At depth, they feed on squid which they stun with powerful blasts of focused echolocation clicks, before crushing them with their peg-like teeth.
Sometimes white, ring-shaped, scars from the suckers on the squids’ tentacles remain on the distinctively blunt heads of these fascinating deep sea predators. The dark wrinkled skin is dusky grey to brown, long strips of which, peel off their bodies like translucent onion skins while swimming.
The broad, triangular-shaped dark tail flukes often have a ragged trailing edge, evidence of shark and killer whale attacks on these massive animals. When threatened, sperm whales form a circle, heads inwards, and thrash the water with their tails to dissuade predators from attacking them or their calves.