BBC Oceans: Southern Ocean

In the second installment of BBC’s nature documentary Oceans, Paul Rose and his team of marine explorers travel to Tasmania to investigate why certain parts of the Antarctic Ocean are warming twice as fast as the rest of the world’s oceans. The Southern Ocean may offer a glimpse into the future of life on Earth – the impact of global warming and climate change. The most evident sign of this phenomenon is the decimation of Tasmania’s giant kelp forests over the past decade to mere patches of hardly five percent their former size. The rise in sea temperatures is itself a major cause, but the team discovers that another perpetrator is the sea urchin – an invasion that has devastated the environment into a barren rocky wasteland. The disappearance of these forests threatens the rich biodiversity normally sustained by kelp and endangers the habitat of the elusive weedy seadragon. We learn that a shift in the East Australian Current brings warm water from the equator farther south than before. Part of a solution to the problem may be the reintroducing of rock lobsters (crayfish) as they prey on sea urchins.

The Antarctic Ocean not only offers a glimpse into the future, it also offers a glimpse into the past. A network of sea caves, namely, contain fossils of ancient shell fish who lived some 300,000 million years ago, which are identical to specimen found across the ocean in Antarctica. Tasmania, in other words, broke off the Southern Pole. Furthermore, strong currents and roaring storms have taken many victims so that the ocean bed is littered with thousands of shipwrecks off Tasmania alone. In the southwestern Sunken Valley, tannin in the surface water from the peat soil filters sunlight, which allows creates to thrive in conditions otherwise found over a thousand feet deep, such as sea whips and sea pens. The team, moreover, discovers that Maori octopuses get stranded by the dozens every year in the secluded Eaglehawk Bay as the access to the open sea is blocked off by a small strip of land. As an extra treat the team dive with fur seals that were once hunted to the brink of extinction, but are now recovering in vigorous colonies on Tasman Island. As informative as the program is, the Cricket is still annoyed by the so-called “human dimension” of the show. More marvelous marine life, please, and less talking heads.