Sign language

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

Blue Planet II

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

BBC One Wales

Wales

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

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

BBC One Wales HD

BBC One Scotland

Scotland

BBC One North West

BBC One West 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

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

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

BBC One South

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

BBC One West

BBC One Yorks & Lincs

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 Oxfordshire

BBC One region covering Derbyshire, Leicestershire and Nottinghamshire.

BBC One East Midlands

BBC One Channel Islands

BBC One Cambridgeshire

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

BBC One HD

BBC One London

London

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

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

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

John Ruthven

Katie Hall

Blue Planet II: Series 1: Episode 4: Big Blue

Big Blue

Episode 4

Episode 4: Big Blue

BBC One - Blue Planet II, Series 1, Big Blue

This vast ocean desert where sperm whales must dive 1,000 metres just to feed.

The wildlife documentary series narrated by David Attenborough explores a vast ocean desert where sperm whales must dive 1,000 metres just to feed.

The big blue is the world's greatest wilderness, far from shore and many kilometres deep. It's a vast marine desert where there is little to eat and nowhere to hide. Yet it's home to some of the biggest and most spectacular creatures on earth.

This episode reveals what it takes to survive in this savage and forbidding world. We witness feats of incredible endurance, moments of high drama and extraordinary acts of heart-wrenching self-sacrifice.

Every animal in the big blue must find their own unique way to survive. Sperm whales have the largest brains in the world. They live for 80 years, and we are only now beginning to learn the extraordinary complexity of their language of clicks - thought to coordinate the whole family in everything from childcare to hunting. With special pressure-proof cameras, we witness record-breaking feats of endurance as they hunt for squid a kilometre down into the abyss.

Many smaller creatures find sanctuary in this great wilderness. Only recently have we begun to solve the mystery of where baby turtles disappear to in their early years. They leave the crowded waters of the coast and head to the open ocean, where they use floating debris like logs as life rafts. Here they remain until adulthood, adrift on the high seas in relative safety away from coastal predators.

Over half of all animals in the open ocean drift in currents. Jellyfish cross entire oceans feeding on whatever happens to tangle with their tentacles. The jelly-like Portuguese man-of-war can harness sail power to fish with its deadly tentacles. Sometimes there is a brief explosion of food in this marine desert, but ocean hunters must be fast to make the best of this bonanza. We witness super pods of up to 5,000 spinner dolphins racing to herd vast shoals of lanternfish, briefly caught at the surface where it is thought they spawn. New aerial footage reveals, for the first time, the truth to a centuries-old sailors' legend of the 'boiling seas' - the spectacular feeding frenzy of 90kg tuna and dolphins smashing through the lantern fish shoals turning the sea white with foam.

Raising your young in this great wilderness is a huge challenge. The episode follows two very different ocean voyagers that show amazing care. We get closer to solving the mystery of where the biggest fish in the sea, the whale shark, gives birth. The pregnant females make an epic journey across the Pacific to the Galapagos Islands. Scientists now think it might be here that the pregnant females give birth to their pups in the safety of the depths. And in the freezing south Atlantic, a pair of ageing wandering albatrosses give their all to raise their very last chick.

Yet even in the big blue, thousands of kilometres from land, there is evidence of human activity. An estimated eight million tons of plastic is dumped into the oceans every year. Globe-spanning currents carry it into the heart of every ocean, often with tragic consequences. In the Atlantic waters off Europe we follow a family of pilot whales whose calf has recently died. One possible cause of death is poisoning by its own mother's contaminated milk. As plastic breaks down it combines with other pollutants that are consumed by vast numbers of marine creatures. In top predators like pilot whales, the toxic chemicals can build up to lethal levels.

Accessibility links

Programme Index

Blue Planet II

Series 1

Episode 4: Big Blue

Contributors

Genres

Formats

Brand

Series

BBC Two Northern Ireland

About BBC Two