Nigel Marven sets out on another adventure, this time focusing on grey whales.
Up and down the coastline, Nigel Marven meets whale-watchers, scientists and researchers.
Following Canadian scientists as they uncover a buried skeleton of a blue whale.
One of the most wide-spread mammals on the planet, they inhabit every ocean.
A long spiral tooth sticking out the front of your face must be quite cumbersome.
The exact function of the narwhal's tusk has troubled scientists for years.
The spiral tusk typifies this extraordinary whale.
Dolphins are a kind of toothed whale and are incredibly intelligent.
The cetaceans include both the baleen and toothed whales.
No visit to New Zealand is complete without spotting its spectacular marine life.