A weedy seadragon sets out on an epic quest to give his young the very best start in life. Unlike the mangrove forests and prairies of sea grass, its existence in the open seas is only temporary. Here sunlight powers the growth of enchanted forests of kelp, mangroves and prairies of sea grass. Further along the coast, the greatest gathering of cuttlefish in the world takes place, as males battle it out for the right to mate. A metre-long, ferocious-jawed Bobbit Worm hides in its tunnel. Monocle Bream retaliate by squirting water to expose its sandy lair. Today, thanks to protection, sea otter numbers are recovering, along with the health of the forest.
We witness feats of incredible endurance, moments of high drama and extraordinary acts of heart-wrenching self-sacrifice. Episode 5 : Green Seas Footage of wildlife inhabiting underwater kelp forests, including thousands of giant cuttlefish spawning along a restricted area of rocky reef off the south coast of Australia. Vast numbers of the ocean's baby fish start their lives in the green seas. A remarkable Grouper uses the fish equivalent of sign language to collaborate with an octopus, flushing their prey out of hiding holes. Larger males use brute force to drive off competition, while their smaller rivals use deception by mimicking the appearance of females. When a popup box asks for the decryption key, paste the decryption key found above. The most bountiful kelp forests are found off the tip of southern Africa, where two great oceans collide.
The richest nurseries of all are the mangrove forests. Episode 4 : Big Blue The big blue is the world's greatest wilderness, far from shore and many kilometres deep. In a surprising story of betrayal, a male shrimp will abandon his mate of possibly 20 years, trading up for a larger female. To outwit her nemesis, the pyjama shark, she uses ingenious tactics, never filmed before. . A metre-long, ferocious-jawed Bobbit Worm hides in its tunnel. Here, grazing green turtles are stalked by tiger sharks.
In warmer waters another green sea takes hold. Yet it's home to some of the biggest and most spectacular creatures on earth. The programme also features tiger sharks hunting for green turtles in fields of seagrass and spider crabs trying to avoid predators while they shed their shells. This episode reveals what it takes to survive in this savage and forbidding world. Microscopic algae flourish into vast blooms, providing a feast for plankton-feeding fish like billions of anchovies.
The army marches into the shallows and starts to pile one on top of each other, building mounds over a metre high. This episode takes us on an epic journey into the unknown, a realm that feels almost like science fiction. Soft-bodied and weakened, they must avoid the patrolling four-metre-long stingrays. Even raising your young can be tough in such a competitive place. A turtle heads to the reef's equivalent of a health spa - but she must use trickery to avoid the queue. Every animal in the big blue must find their own unique way to survive. A smaller, sneaky male uses subterfuge, even pretending to be a female, to confuse rivals and get his girl.
They are the most abundant but fiercely competitive places in the ocean to live. A remarkable Grouper uses the fish equivalent of sign language to collaborate with an octopus, flushing their prey out of hiding holes. 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. But urchins can swarm in vast numbers and even attack and fell the kelp forest itself, creating vast 'urchin barrens'.
And there is one other green sea that supports more life than all the rest combined. Straddling the boundary between land and sea, they provide shelter for the juvenile fish. By keeping turtles on the move, tiger sharks prevent the seagrass meadows from being overgrazed. Scientists already think that there is more life in the deep than anywhere else on earth. Survival in these undersea mega-cities is a challenge with many different solutions. Almost a hundred different species of shark patrol these waters, driving one resident - the common octopus - to become the ultimate escape artist. In a filming first, we reveal great rafts of sea otters now numbering in their hundreds.
Back in the late 1800s, sea otters were hunted for their thick pelts to near extinction. 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. We discover alien worlds, bizarre creatures and extraordinary new behaviours never seen before. It's a vast marine desert where there is little to eat and nowhere to hide. Along the Pacific coast of North America stand, at 60 metres high, the largest and perhaps most diverse kelp forests in the world. In Japan, a shipwreck is home to the Asian sheepshead wrasse, which can change gender, while in the polar north, walruses struggle to find ice floes for their pups to rest on as climate change takes its toll on the environment. Post back here if u run into any problems.
All is not entirely lost, thanks to the return of a ravenous forest resident - sea otters. And with them gone, urchin numbers rose, destroying many forests. We encounter savage hordes of Humboldt squid hunting lanternfish in the depths and coral gardens flourishing in absolute darkness, with more species of coral to be found in the deep than on shallow tropical reefs. 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. Like its predecessor, The Blue Planet 2001 , it is narrated and presented by naturalist Sir David Attenborough. But dont worry we will help you.