text
The purse seine is a vertically hanging net with floats on its surface line and lead weights on its bottom edge. Attached to the weighted line are rings strung together by a drawstring wire. Ships encircle entire schools with the outstretched purse seine, then they pull the drawstring wire tight to trap the fish inside.
Traps are one of the most environmentally friendly fishing methods. They are highly selective, since fishermen can release unwanted fish alive when the traps are hauled up. They also do little to no harm to the ocean floor or other oceanic surroundings, as they are nonmobile. However, there is a huge problem associated with traps - ghost fishing.
In 1995, the FAO deemed ghost fishing to be one of the most seriously negative impacts in the present capture fishery industry (Matsuoka). When traps are lost, from storms or human negligence or otherwise, the vast majority will continue to catch and trap fish or other ocean life for months, or even years. Ghost fishing in some commercial stocks is estimated to be equal to 5-30% of the annual catch levels (Laist). There are already some measures being taken to prevent ghost fishing: the FAO code of conduct states that States should try to minimize catch by lost or abandoned gear, and many countries including Sweden, Poland, New Zealand, and the United States all have gear retrieval programs (Brown).
Gear retrieval programs, however, are not the best way to prevent ghost fishing. A study by Brown and Macfayden indicates that while these programs save fishermen about $32,000 per fleet per year, the time and money spent in retrieving the gear exceeds $65,000. But if these programs are used along with measures that prevent gear loss in the first place, the cost will decrease significantly. Another possibility is to develop new technology that allows for easier and cheaper retrieval of lost nets and traps.
Another measure being taken is the requirement of escape mechanisms. <<INFO>>. If these requirements are made more strict and widespread, then ghost fishing should decrease dramatically.
Unfortunately, there is little data about the effectiveness of escape mechanisms, or even truly accurate data regarding the impacts of ghost fishing on fish populations; most of the numbers discussed above are mere approximations. This is another area in which we can improve