The Blue Planet: the seven best moments from the original David Attenborough series

As the second series of the BBC's pioneering ocean documentary Blue Planet is well underway, we revisit some of our favourite sequences from the original 2001 programme.

The blue whale

Stunning aerial footage brought the rarely seen blue whale, the largest animal on Earth, into our living rooms. The majestic shot of the great mammal breaching the surface, its tail shining like an aeroplane's wing as it rises above the waves, remains a truly timeless TV moment.

The gray whale carcass being slowly eaten

Watching a gray whale calf become separated from its mother before being hunted and killed by a pod of orcas in The Blue Planet's first episode was an intensely distressing experience (except, perhaps, for the hungry orcas involved).

Far more insidiously haunting, however, was the documentary's depiction of the slow decomposition and consumption of another gray whale body, deep below the ocean surface.

Filmed across the course of a year and a half, the compellingly macabre footage showed how the masses of whale-flesh provided sustenance for everything from sharks to masses of wriggling, eel-like hagfish.

By the time the 18 months were up, the great animal's bones had been picked clean.

(Unfortunately, we can't find a clip of this sequence - but you can find the full episode on BBC iplayer.)

The colour-changing walruses

The only thing better than a beach full of walruses? A beach full of colour-changing walruses, transforming from cool, heat-conserving white to an improbable bright fleshy pink.

The coral spawning

"Bundles of eggs and sperm float to the surface to mix with others further along the reef," explained Attenborough, in characteristically calming tones, as a surreal underwater fairyland – a hidden, nocturnal snowstorm  – unfurled before our eyes. Thanks to the romantic orchestral score and the strangely intimate-feeling footage, it remains one of the series' most delicately beautiful sequences.

The sardine feeding frenzy

Life in the open ocean can be nasty, brutal and short. As the breathless feeding frenzy footage shown in episode three attested, this is particularly true if you happen to be a sardine. There was no safety in numbers for the unlucky shoal in question, especially after a hungry giant, a Sei whale, decided to join the hordes of marlin and tuna already picking them off.

The alien world of the deep ocean

 The combination of inky deep ocean darkness and startling pockets of bioluminescence helped to make the second episode of the show, The Deep, feel more akin to science fiction than science documentary... and the deep sea fish themselves, including the razor-toothed, light-lure-dangling, floating head-like anglerfish, were winningly grotesque.

The 'Dumbo' octopus 

In 2001, when The Blue Planet first aired, this cartoonishly bizarre creature – nicknamed Dumbo due to its "extraordinary flapping ears" – had only recently been discovered.