Blue Planet II

Editorial

BBC Two

Knowledge, drama, comedy and the arts for a broad adult audience.

BBC Two is a lively channel of depth and substance, carrying a range of knowledge-building programming complemented by great drama, comedy and arts.

BBC Two Northern Ireland

Documentaries

Factual: Science & Nature: Nature & Environment

Documentary series, presented by David Attenborough, exploring the planet's oceans.

Wildlife documentary series, presented and narrated by David Attenborough, exploring the planet's oceans.

Series 1

BBC Four

CBBC

The BBC West region started on 1st September 1957 as part of the BBC Television Service, before becoming BBC One West.

BBC One West

The BBC South West region started on 20th April 1961 as part of the BBC Television Service, before becoming BBC One South West.

BBC One South West

The BBC South region started on 5th January 1961 as part of the BBC Television Service, before becoming BBC One South.

BBC One South

BBC One London

London

BBC One West Midlands

BBC One region covering Derbyshire, Leicestershire and Nottinghamshire.

BBC One East Midlands

The BBC East region started on 1st May 1959 as part of the BBC Television Service, before becoming BBC One East.

BBC One East

BBC One North West

The BBC North East & Cumbria region started in 1959 (tbc) as part of the BBC Television Service, before becoming BBC One North East & Cumbria.

BBC One North East & Cumbria

BBC One Yorkshire

BBC One Oxfordshire

Formerly part of a wider BBC One South East region that included London and part of the South region. Separated from BBC One London 2001-09-03 following reorganisation of the South East region.

BBC One South East

BBC One Cambridgeshire

BBC One Channel Islands

BBC One Yorks & Lincs

BBC One Scotland

Scotland

BBC Northern Ireland region started on 19th April 1955 as part of the BBC Television Service, before becoming BBC One Northern Ireland.

BBC One Northern Ireland

BBC One Wales

Wales

Simulcast of BBC One Scotland in high definition. From 14/01/2013

BBC One Scotland HD

Simulcast of BBC One Northern Ireland in high definition. From 24/10/2012

BBC One Northern Ireland HD

Simulcast of BBC One Wales in high definition. From 29/01/2013

BBC One Wales HD

Simulcast of network BBC One in high definition. From 03/11/2010

BBC One HD

Simulcast of network BBC Two in high definition.

BBC Two HD

BBC Two Scotland

Until 03/01/2009 BBC Two Wales (analogue) was known simply as BBC Two Wales. BBC Two Wales (digital) was BBC 2W. From 03/01/2009 BBC Two Wales schedules on both analogue and digital became identical

BBC Two Wales

BBC Two England

England

Simulcast of BBC Two Wales in high definition

BBC Two Wales HD

Simulcast of BBC Two Northern Ireland in high definition

BBC Two Northern Ireland HD

BBC Four HD

CBBC Channel

CBBC HD

David Attenborough

James Honeyborne

Mark Brownlow

Kathryn Jeffs

Katie Hall

Blue Planet II: Series 1: Episode 5: Green Seas

Green Seas

Episode 5

Episode 5: Green Seas

BBC One - Blue Planet II, Series 1, Green Seas

From enchanted forests to undersea prairies, the planet's green seas teem with life.

The wildlife series narrated by David Attenborough explores the planet's green seas. From enchanted forests to undersea prairies, they teem with life.

It's our green seas, not the blue, that bring life to our oceans. Here sunlight powers the growth of enchanted forests of kelp, mangroves and prairies of sea grass. They are the most abundant but fiercely competitive places in the ocean to live.

The most bountiful kelp forests are found off the tip of southern Africa, where two great oceans collide. Almost a hundred different species of shark patrol these waters, driving one resident - the common octopus - to become the ultimate escape artist. To outwit her nemesis, the pyjama shark, she uses ingenious tactics, never filmed before. 

Along the Pacific coast of North America stand, at 60 metres high, the largest and perhaps most diverse kelp forests in the world. In clearings, bright orange male Garibaldi fish guard territories of short turf seaweed. When spiny urchins invade and graze their crops, the Garibaldi desperately pick them off. But urchins can swarm in vast numbers and even attack and fell the kelp forest itself, creating vast 'urchin barrens'. All is not entirely lost, thanks to the return of a ravenous forest resident - sea otters. Back in the late 1800s, sea otters were hunted for their thick pelts to near extinction. And with them gone, urchin numbers rose, destroying many forests. Today, thanks to protection, sea otter numbers are recovering, along with the health of the forest. In a filming first, we reveal great rafts of sea otters now numbering in their hundreds. 

In warmer waters another green sea takes hold. Off Western Australia, vast prairies of seagrass extend to the horizon. Here, grazing green turtles are stalked by tiger sharks. By keeping turtles on the move, tiger sharks prevent the seagrass meadows from being overgrazed. In this way, sharks have become surprising allies in the fight against climate change - as a patch of sea grass is 35 times more efficient at absorbing and storing carbon than the same area of rainforest.

Once a year, one sea meadow in Australia is overrun by an extraordinary invasion. With the first full moon of winter, strange creatures emerge from the deep - spider crabs. The army marches into the shallows and starts to pile one on top of each other, building mounds over a metre high. They then moult. Soft-bodied and weakened, they must avoid the patrolling four-metre-long stingrays.

Further along the coast, the greatest gathering of cuttlefish in the world takes place, as males battle it out for the right to mate. But even among these giant cuttlefish, the largest of their kind, it's not always size that counts. A smaller, sneaky male uses subterfuge, even pretending to be a female, to confuse rivals and get his girl. Even raising your young can be tough in such a competitive place. A weedy seadragon sets out on an epic quest to give his young the very best start in life.

Vast numbers of the ocean's baby fish start their lives in the green seas. The richest nurseries of all are the mangrove forests. Straddling the boundary between land and sea, they provide shelter for the juvenile fish. But in the mangroves of Western Australia lives a deadly assassin - the 40cm-long zebra mantis shrimp. In a surprising story of betrayal, a male shrimp will abandon his mate of possibly 20 years, trading up for a larger female.

And there is one other green sea that supports more life than all the rest combined. Unlike the mangrove forests and prairies of sea grass, its existence in the open seas is only temporary. Microscopic algae flourish into vast blooms, providing a feast for plankton-feeding fish like billions of anchovies. In Monterey Bay, California, the giant shoals draw in thousands of dolphins, sea lions and humpback whales who all race to claim their share of the feast.

Accessibility links

Programme Index

Blue Planet II

Series 1

Episode 5: Green Seas

Contributors

Genres

Formats

Brand

Series

BBC Two Northern Ireland

About BBC Two