Sperm Whale - Physeter macrocephalus

This species can dive easily beyond 1000 metres deep; some researchers estimate that its maximum depth is around 3 kilometres. 
They start their vertical dive with this typical flukes-up position. 
Note the nuckles on its back.

Sperm whale

This Sperm whale (Physeter macrocephalus) shows its characteristic "flukes-up" dive.

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