As global fish stocks decline and fisheries collapse, the arguments tend to center around catch quotas and territorial rights. These have been the subject of hours of national and international debate and negotiation, and have even lead to violence on a few occasions. With governments and fisheries focused on political and economic survival, respectively, nobody at the negotiating table has much time to devote to the actual survival of the thousands of non-target species that get trapped in the nets or caught on the longlines every year. In the fishing wars, these are the innocent civilians, caught in the crossfire. They include not only larger animals, like marine mammals, turtles, and seabirds, but also countless millions of fish and invertebrates that make up a vital part of the marine food web. It was estimated that, in 2000, over 2 billion pounds of non-target organisms (bycatch) were discarded by US fishing boats – and the US only constitutes 6% of the global fishing industry. The AAAS annual meeting in Denver, CO (February 13–17, 2003) included two marine symposia on various aspects of bycatch. Researchers are tackling the problem from a number of different angles. These include tracking studies using electronic tags, to gain a better understanding of roaming, feeding and breeding habits, and to see where the animals will intersect with fishing fleets, and developing new technologies to scare non-target species away from fishing equipment, or to allow them to escape if they get caught. There have been some successes. Pelagic longline fisheries kill many seabirds, who dive onto the baited lines and are dragged into the water and drowned. Simple preventive measures, such as setting the lines at night and using bird-scaring streamers or weighted lines that sink more quickly, can substantially reduce seabird mortality. Turtle Excluder Devices – metal trapdoors in the back of trawl nets – allow many turtles to escape unharmed, though the problem of thousands of turtles caught on pelagic longlines remains unsolved. Observers have been placed on fishing boats to monitor mortality, but these are few in number, so that much of the bycatch goes unreported and unrecorded, simply driving the problem “underwater”. What we need is a radical change in the attitudes of governments and fisheries managers towards environmentally sensitive practices and protective technologies. As Martin Hall of the Inter-American Tropical Tuna Commission (San Diego, CA) put it, “We need to persuade fishermen to fish better”. Given the reality of falling fish stocks, a certain amount of redundancy among the fishing community is inevitable – particularly if global fishing effort continues at the present levels. Hall would like to see fishermen undergo a form of “natural selection”, whereby those who use best practices to reduce bycatch and minimize damage to marine ecosystems inherit the fisheries of the future. He recognizes that the approach needs to be non-threatening; fishermen must be offered reasonable goals and easy-to-implement solutions that are clearly to their advantage. There is evidence that this is sometimes possible – in a single trial of a chute used to launch longlines, seabird bycatch was reduced by 98%, while bait costs were reduced by 60%. Where win–win solutions like this exist, there is some hope for the future. The combination of economic advantage and the desire to avoid regulatory intervention, and even public disapproval, should eventually encourage fisheries to adopt less environmentally damaging techniques. Unfortunately, few such solutions have been identified to mitigate the effects of bottom trawling, which is by far the most efficient and profitable industrial fishing technique, but also the most destructive – and responsible for the highest percentages of bycatch. There have been some recent efforts to get fishermen, fisheries managers, and scientists round the same table. International Fishers' Forums and consensus groups have been convened to tackle these issues and try to come up with incentives for fisheries to avoid or minimize bycatch. However, there is much still to be done: adjustment of international agreements to address bycatch issues (current ones rarely mention non-target species) and the means to implement and enforce them; more research on the affected species; the continued development (preferably by fishermen themselves) of new technologies and techniques to reduce bycatch; and improved consumer education, since consumer pressure can have a positive impact. In the end, this battle may be won or lost in the supermarket. A vociferous consumer lobby could act as the counterbalance to political pressure from the small but powerful fishing industry. In the future, public demand for seafood caught in an environmentally responsible way could help to make the deep oceans a safer, more peaceful place again. Dr Sue Silver,Editor-in-Chief
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