BBC Oceans: Sea of Cortez

In 2008, BBC Two ran an eight part nature documentary series about the world’s oceans. The first episode is about the Gulf of California, or Sea of Cortez. The story begins with the near disappearance of hammerhead sharks in the region – wiped out by commercial fishing (mostly for shark fin soup marketed in Asia). But sad as that certainly is, a sea of change is taking place naturally. The dolphin population has increased, and sea lions are thriving after the local colony has adapted to fishing in deeper waters now that the sardines have thinned out. More threatening is the growing presence of the cannibalistic predatory Humboldt squids, who’ve mastered hunting in packs. Yet that presence has attracted large numbers of sperm whales who no longer need to migrate (at least not the females) in order to survive. The program also includes images of the hydrothermal vents along the San Andreas Fault, as well as the wreckage of Chinese vessel once smuggling immigrant workers to the us now becoming an artificial coral reef. The team includes expedition leader Paul Rose, maritime archaeologist Lucy Blue, maritime biologist Tooni Mahto, and environmentalist Philippe Cousteau (the grandson of Jacques Cousteau). While I mean no personal offensive – Mahto and Cousteau are definitely photogenic – the show focuses too much on them rather than on the beautiful wonders that are the program’s subject.

Life: Creatures of the Deep

Life on Earth began in the Ocean Deep – and some of the most ancient life forms on our planet are marine invertebrates, the topic of this installment of the most astonishing nature documentary so far produced. We return to the hydrothermal vents (seen in Planet Earth) around which it all began. It is there that Pompeii worms survive the scalding, volcanic heat, together with white crabs and enormous tube worms. When krill rise up at night from the abysmal depth to the surface in the Sea of Cortez off Mexico to feed on plankton, they attract shoals of predatory sardines that in turn attract hundreds of Humboldt squid that herd the fish as a pack and grab their meal with dangerous tentacles. Underneath the Antarctic sea ice in springtime life flourishes in a colorful garden of starfish, sea urchins, and nemertean worms. A sight so incredible, it’s almost unearthly! Then there’s the huge fried-egg jellyfish hunting among a swarm of 100,000 Aurelia jellyfish, using its tentacles like harpoons to catch prey. Another amazing scene shows hundreds of thousands of armor-plated spider crabs marching to the shallows off South Australia to molt their old shells and to mate enthusiastically while they’re together in such vast numbers. But then they are under threat from a stingray that is so choosy it only catches the softest shelled crabs.

The highly intelligent cuttlefish (who have the largest brain size relative to its body among invertebrates), the chameleons of the sea, can quickly change the color of their skin, flashing different colors, not just as warning or camouflage, but also deception – for instance to mimic the color of a female, confusing a larger male, and allowing the smaller one to mate on the sly. We also revisit the 14-ft. Pacific giant octopus off the coast of British Columbia that sacrifices her life caressing her only hatch of a hundred thousand eggs to protect them from algae and fish. The struggle for survival proves itself, again, when a large sun-starfish feeds on her deceased body, gets trapped by spiny sea urchins, and comes under attack from a king crab that amputates one of its arms. In sheer awe, we witness a coral reef forming around the rusty hulk of a shipwreck, feeding and fighting, and spawning after the November full moon. The program ends with the most wondrous splendor of the Great Barrier Reef, the largest living structure on earth. I can only repeat myself: watch the series!