Africa Geographic November 2007 [antikvár]

founder's note mm IF m- iV= .i i, "Vll tt r •] ' 7 • mil im 'I,,'! mi , mostly this other world, which extends over some 70 per cent of our planet's surface, is invisible to us. And that is a bad thing My family has a cottage in a small private nature resen/e about an hour's drive from Cape Town. Sheer sandstone cliffs tower behind us while in front, beyond a narrow fringe of garden, the land drops away in a tumble of boulders to the ceaseless suck and surge of the sea. It is a place of great tranquillity where, looking out over the immense inscrutable ocean, it is not hard to fool oneself that all is well with the world. For most of us, our sense of what lies beneath the swell is built from books, underwater film documentaries and the Images from gifted people such as Thomas P. Peschak. Occasionally we might glimpse a seal playing in the waves or, better still, witness a whale breaching, but mostly this other world, which extends over some 70 per cent of our planet's surface, is invisible to us. And that is a bad thing, because I am sure that if it were not, we would be even more worried about the state of the oceans than we are about the loss of our rainforests, such Is the mayhem that our species has wrought upon the marine environment. We know that many commercial fisheries around the world are in a state of collapse, with huge consequences for humans who depend on marine protein for nourishment. We know that between 26 and 73 million sharks are killed every year as a direct consequence of an insatiable Asian demand for shark-fin soup that can sell for more than LIS$150 a bowl in top Chinese restaurants. Dr ten Compagno, a Cape Town-based biologist who is a world authority on shark biology and consen/ation, has stated that some large shark populations have plunged to five per cent of their original size. We know, too, that coral reefs - the rainforests of the oceans in terms of their biodiversity - are In dire straits, due partly to pollution and destructive fishing, but increasingly because of warmer water Corals live within a very narrow temperature range and, when stressed by either cold or heat, will expel the algae that give them food and colour, resulting in the phenomenon described as coral bleaching. Some experts predict that within a century very large tracts of coral reef will be lost to us forever And so, we return to the greatest challenge of our time - climate change and a warming planet fuelled by excessive emissions of carbon dioxide and other greenhouse gases. The oceans are estimated to have absorbed more than a third of human-generated carbon dioxide. But the cost to the marine environment has been increasing acidity, which could well prove deadly for all shelled organisms whose protective shields will simply corrode away Not only will we lose corals, crabs and lobsters, but also the tiny plankton that form the bottom of the marine food chain. And, just as surely as a runaway whaling industry, this will see the demise of the baleen whales such as those magnificent humpbacks that are the subject of Jaco Barendse's 'Head of steam' (page 40). I think I have just destroyed that sense of tranquillity whilst sitting by the sea. •i Africa Ceographic is editorially and financially independent, It enjoys the support and endorsement of several non-government organisations, but it is not affiliated in any way to these bodies or to any other publishing, environmental or political interest group. Africa CeographiciU'wei to foster an awareness of wildlife, consen/ation, eco-travel, indigenous cultures and the general environment. It consistently advocates the wisest use of natural resources in a manner that involves and is of real benefit to the people ol Africa. Africa Geographic is published 11 times a year.