Wild Sea A History of the Southern Ocean

The Southern Ocean, that vast body of water that flows unhindered around Antarctica, has to be one of the most forbidding oceans on our planet. Its latitudes are referred to by increasingly unnerving names the gale-force winds that have terrorised mariners since they first set sail here – the roaring forties, the furious fifties, the screaming sixties. Its waters are so cold that they are actually below freezing in places, with only their salinity preventing them from freezing solid (fish here have evolved antifreeze proteins!) As a consequence of these extreme conditions, this region has long remained unexplored. But, as historian Joy McCann shows, explore it we did. Brace yourself for a gripping piece of environmental history, marked by heroism as much as hubris, and curiosity as much as cruelty.

Our planet cares little for cartography. From its perspective, there has only ever been one ocean, one all-enveloping fluid lapping its shores. What we now recognize as the Southern Ocean took shape some 40 to 20 million years ago as the forces of plate tectonics ripped up Gondwanaland, pulling apart Australia and Antarctica. Its completion arrived when the Magellan land bridge between South America and Antarctica was breached (see also my review of Land Bridges), opening up the Drake Passage and allowing the ocean to flow unimpededly around Antarctica in a so-called circumpolar current. This, as McCann explains in her introduction, is the geographical setting of the Southern Ocean.

Humans, meanwhile, have long speculated about the existence of a Southern continent, going back as far as the second-century astronomist Ptolemy. Although rumoured sightings of Antarctica by European explorers go back at least as far as 1599, it was not until the mid-1700s that in particular England and France started despatching ships on missions that were equal parts conquest and discovery. These were the times of James Cook commanding the HMS Endeavour, Resolution, and Adventure (see also Captain James Cook), and later James Clark Ross aboard the HMS Erebus and Terror (see also my review of Erebus: The Story of a Ship). Particularly influential, and featured here extensively by McCann, was the HMS Challenger expedition, which has been hailed as birthing modern oceanography (see also Endless Novelties of Extraordinary Interest). It also saw merchant’s vessels take crazy risks to try and find shorter routes to India. McCann’s description of sailing boats venturing into the roaring forties and having to turn north at the right moment at a time when they could not even fix their longitude beggars belief.

McCann has organised each of her chapters around a natural attribute of the Southern Ocean (ocean, wind, coast, ice, deep, current), rather than stick to a strict chronology. This means she sometimes retreads the same historical path but from a slightly different perspective. One such perspective that leaves a bloody trail through the book is that of brutal exploitation. The cold waters of the Southern Ocean feed a huge number of seals, penguins, whales, and fish – and humans have ruthlessly hunted these to near-extinction in roughly that order. Seals were hunted by the millions for fur starting in the 1800s. Penguins fell victim not long after. An estimated two million (!) whales were harpooned, sliced up, and rendered into oil – lubricating and lighting the Industrial Revolution back in Europe (see also A Savage History). The ecological consequences of this slaughter still reverberate through these ecosystems (see also Whales, Whaling, and Ocean Ecosystems) and as my review of The Outlaw Ocean showed, fish and whales remain under threat.

McCann pays as much attention to the natural world in this environmental history. Though not intended as a primer on the biology of marine mammals and seabirds, the pages of Wild Sea are nevertheless littered with details on the lives of whales, seals, penguins, albatrosses, petrels, and fulmars. She has left out some delightfully risqué details on penguins, but I will be covering these in an upcoming review of A Polar Affair. I was very pleased, however, to see her go into the microscopic creatures underlying all this biological richness, such as the diatoms (single-celled algae) and zooplankton, notably the large Antarctic krill (see my review of Biology and Ecology of Antarctic Krill).

The physical environment also features prominently. Much like generations of sailors before her, McCann marvels at ice – the bergs, the floes, the glaciers – and the sometimes otherworldly play of the light here. But I was fascinated by what lies beneath. There is the ocean’s bathymetry (the underwater topography) and the incredible story of the mapping of the ocean floor (see also the biography of Marie Tharp: Soundings). These efforts revealed the existence of mid-ocean ridges that helped the theory of plate tectonics finally find wide acceptance (see Mid-Ocean Ridges and my review of The Tectonic Plates are Moving!).

But McCann really enraptured me with the currents. These slowly travelling bodies of water shape our climate on a planetary scale (see also The Great Ocean Conveyor) and understanding their three-dimensional nature is an ongoing mission (see also Ocean Circulation in Three Dimensions). Invisible to us, this underwater realm features waves, eddies, gyres, and underwater storms of staggering proportions. McCann captures some of this mysterious grandeur in her descriptions: “In the Weddell and Ross seas, which lie on either side of West Antarctica, the water becomes heavy as salt leaches out of the ice shelves, forming waterfalls below the ocean surface that plunge up to 2 kilometres into the abyss.” Her helpful notes link to an amazing animation put together by the Research School of Earth Sciences at the Australian National University.

Wild Sea is an incredibly diverse book and McCann’s writing is informative and absorbing. In just 200 pages she manages to touch on a plethora of topics including history, oceanography, climatology, ecology, and marine biology. There are other amazing stories in this book I have not mentioned, one inspiring example being footage of a traditional whale-calling ceremony culminating in a meeting of indigenous leaders from around the globe. As an introduction to the many entangled natural and human histories of the Southern Ocean, this one comes highly recommended.