|Pillage of sea by fishing industry|
*For every kilo of shrimp landed 4.75 kg of marine life is destroyed. 35% of all bycatch waste is caused by shrimp fishing
*Japanese longline tuna fishermen killed an estimated 44,000 albatross in the southern ocean in 1989.
*About 124,000 turles die in shrimp trawls each year.
*More than half of the marine life caught in drift nets are dumped back in the sea.
*About a third of the total amount of haddock caught in the north sea is thrown away as bycatch, 40% of all herrings.
There are plenty more fish in the sea! It's a phrase that embodies our belief in the inexhaustible resources of the world's oceans. Yet around the world, fisheries are collapsing. The United Nations Food and Agriculture Organisation estimates fisheries waste between 18 and 40 million tonnes of marine life each year. If that doesn't mean much to you, imagine somewhere between two and five million African elephants being culled each year and you will begin to get a feel for the devastation.
This profligate wastage is called bycatch, meaning everything fishermen catch unintentionally, ranging from undersized fish to marine mammals tangled in drift nets, seabirds drowned on longlines or turtles trawled up in shrimp fisheries. Bycatch has been around since Biblical times. Matthew (13:47-48) says: 'The kingdom of heaven is like a net that was thrown into the sea and caught fish of every kind; when it was full, they drew it ashore and put the good into baskets but threw out the bad.'
However, recent technological advances in fishing techniques, coupled with the development of ever bigger and faster boats, some of which can stay at sea for months on end, has escalated the problem to oceanic proportions. Every diver shudders at the thought of blundering into a near-invisible curtain of monofilament netting; and birds, sharks, turtles and marine mammals entangled in driftnets have drawn widespread public concern.
The largest nets can take as many hours to haul back on board as the time spent fishing. Dead fish in the net attract sharks and other predators which themselves get caught. Half-eaten fish just add to the wastage. Other fish drop out of the nets before they are retrieved. Bycatch can account for up to 55 per cent of the total catch taken by driftnets. The environmental organisation Earthtrust calculated that in order to take 106 million neon flying squid, more than 39 million other fishes, 700,000 blue sharks, 270,000 seabirds, 140,000 salmon, 26,000 marine mammals and 406 turtles were caught by the North Pacific Japanese squid drift net fishery during 1990. Thankfully, in 1992 the United Nations banned large-scale drift netting in international waters, but before the ban more than 50,000km of drift nets were set each night.
Worn out nets continue to ghostfish the oceans and it has been estimated that at the height of drift netting up to 640 miles of nets were lost in the North Pacific Ocean each year. Other fisheries have also hit the headlines over bycatch. In the late Eighties consumer outrage over the practice of setting tuna purse seine nets around schools of dolphin in the Eastern Tropical Pacific (ETP) forced international legislation and 'dolphin-friendly' labelling.
More recently conservationists have been arguing whether or not to support changes in the US on such product labelling. Many people who thought the battle was won are surprised to find organisations such as the World Wide Fund for Nature and Greenpeace supporting new laws which appear to condone killing dolphins. It's an issue dogged by the complexity of the bycatch problem. The original legislation aimed to eliminate dolphin deaths by setting limits on bycatches which were to be decreased each year until 1999.
These changes certainly cut the number of dolphins caught in the ETP from a staggering 133,000 taken in 1986, and they have allowed dolphin populations to recover. But entirely eliminating dolphin deaths is altogether more complicated. In 1994, 4,095 dolphins died in the ETP tuna fishery. The new rules allow up to 5,000 dolphins to be caught each year until 2001. Importantly, by then the annual bycatch of each species should be no more than a one-thousandth part of the recovering population and must not threaten further recovery.
Some campaigners, such as the Whale and Dolphin Conservation Society, are worried that as stocks recover, this one thousandth part of the population which is allowed to be caught will mean unacceptable numbers of dolphins being killed. They want the Inter American Tropical Tuna Commission (IATTC) to ban altogether nets set around dolphins, claiming consumers believe 'dolphin-friendly' means no dolphins are killed during fishing. But Dr James Joseph, Director of the IATTC which negotiated the new rules, points out that since regulations were introduced into the ETP fishery, 85 per cent of the US fishing fleet (the main target of the rules) has moved to the less regulated Western Pacific, or has been sold to foreign companies or scrapped. Countries outside the IATTC still set nets around dolphins.
While the number of such sets has only decreased by about a quarter, the number of dolphins killed per set net is down 96 per cent. The fall in dolphin deaths is more to do with fishermen getting better at releasing encircled dolphins than the outlawing of this type of fishing. Meanwhile in the Western Pacific, where many more vessels are now operating, nets are often set around floating logs and debris which attract tuna. The trouble is they attract other species as well, which then get taken as bycatch.
IATTC research found that for every one dolphin killed in nets set around dolphin schools, nets set around logs wasted 19,542 tuna (mostly thrown away because they are undersized), 138 mahi mahi, 25 sharks and rays, 56 wahoo, 3 yellowtail, 7 rainbow runner, 1 billfish and 0.07 turtles. Ironically, outlawing nets set around dolphins would actually increase the bycatch problem for more vulnerable species. Dolphins could be having grandcalves or even great-grandcalves before a sea turtle breeds once.
For sharks we know hardly anything, except that mortalities in log sets are high. We do know that dolphin mortality is sustainable, but we don't know about sharks or sea turtles, says Joseph. For the animal rights activist, the fate of a charismatic mammal such as a dolphin is paramount. To the environmentalist, the ecosystem and its component populations are even more important.
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