Driftnet fishing is a technique that utilizes gill nets attached to floaters. The nets are then allowed to float freely at the surface of a lake or sea. The net is considered very effective since it is near invisible while underwater. The fishing method involves laying nets 30 feet deep and up to 30 miles wide. The nets are then left to drift overnight before they are retrieved. In 1989, the United Nations passed a resolution to ban drift net fishing in the South Pacific region. Before the ban, regional fishery scientists had stated that the stocks of albacore tuna – vital to the economies of small islands- could be wiped out if Japanese and Taiwanese boats continued drift netting at the same rate. At the time, Taiwan and Japan claimed that research was needed to support the ban, but the position met with harsh criticism from other countries in the region. Japan later reduced its South Pacific drift-net fleet and agreed to accept a moratorium. Taiwan, which is not a member of the UN, also indicated that it would comply with the agreement. The UN resolution, however, left open the possibility of lifting the ban if effective management and conservation measures were taken.
Arguments In Favor Of A global ban on driftnets
Drift nets are not selective, and their use results in a significant bycatch of non-target species such as turtles, sea birds, sharks, and marine mammals. For example, the drift-net fishery for swordfish in the Mediterranean results in the killing of huge numbers of striped dolphins, sperm whales, and smaller numbers of common dolphins, bottlenose dolphins, fin whales, long-finned pilot whales, Cuvier’s beaked whales, and other non-target marine wildlife. Concerns about excessive bycatch in the early 1990s prompted the EU to ban the use of drift nets longer than 1.5 miles (before the ban the average length was 26 miles). Some fishing nations have, however, objected to the regulation and do not enforce. In the late 1980s, pelagic drift nets killed an estimated one million dolphins, porpoises, and other cetaceans, millions of sea birds, and thousands of seals and sea turtles annually. According to figures supplied by the Italian Merchant Marine Ministry, between 1990 and 1991, only 18% of the catch in Italian driftnet fleet in the Mediterranean was swordfish, and the other 82% consisted of 85 different non-target species almost all of which were discarded. Although hard evidence has not been provided, there are anecdotal reports that show substantial reductions in non-target species such as cetaceans in regions that have had intensive drift net fishing.
A significant number of drift nets are lost at sea, particularly during severe storms. The nets are manufactured from synthetic material and are resistant to degradation. The lost nets, also known as ghost nets, continue to snare fish, birds, turtles, sharks, and other marine wildlife for many years. It is difficult to assess the magnitude of the problem, but it undoubtedly increases the mortality of marine wildlife.
The relative economic efficiency of using drift nets in areas with dispersed stock has been taken to suggest that they increase the likelihood of resource overexploitation. Experts who support the argument claim that, as fish stock becomes depleted and more dispersed, the use of drift nets could still be utilized due to their higher economic efficiency, therefore, depleting the fish resource more quickly.
Drift is often criticized for great wastage of fishery resources. Fish caught in drift nets are often left in the sea for several hours before the net is retrieved, which means that a relatively high proportion of fish is spoiled and has to be discarded. The ratio of fish that is rejected due to spoilage is not usually reported. Still, observations made on Japanese vessels operating in the South Pacific suggest that the wastage is approximately 2% of the catch. Drift nets also have a significant fish drop-out (proportion of fish observed to fall off the net as it is hauled). Squid drift net fishery in the North Pacific has drop-out rates of between 3% and 10%. An experiment conducted in England found that seals consumed 5 % of salmon from the driftnets before the net was hauled. Some studies have also found that sharks were attracted to the nets.
Physical Impediment To Sea Traffic
Drift nets also pose significant challenges to other vessels and fisheries in general. Drift nets have been known to ensnare propellers and keels of other vessels occasionally. The frequency and economic consequences of such occurrences are, however, not adequately documented.
Arguments Against The Ban
It has been suggested that a full ban on drift net fishing could address the persisting environmental issues, but no attempts have been made to assess the knock-on effects of banning. According to opponents of the ban, proponents of the same fail to address the inherent weaknesses of a system that allow other forms of fisheries, which might focus on sensitive fishing areas and harm threatened stocks and causes great pressure on fisheries. Proponents of a ban also do not factor in other aspects such as pollution, which significantly affect fish populations. It would appear that putting fishermen off the water is an easier option or perhaps a higher priority than tackling pollution. As per the opinion of opponents, a ban would also undermine inshore fleets to the extent that fishing vessels that have been regarded as models of sustainable practice would have a key method at their disposal taken away.
Socio-economic Impact On Fishing Communities
The socio-economic impact of such a ban has not been disaggregated to port and communities that utilize driftnet fishing. The explanatory memorandum accompanying the ban proposal in the EU argues that the total value of small scale driftnets represents 0.14% of the total value of the UK landings in 2011. It asserts that the overall socio-economic impact of a total ban would be irrelevant at the national and sub-regional levels. Experts have argued that the wording could be seen as insensitive and inflammatory since the income generated by small scale fishing is anything but irrelevant for those who still rely on the practice.
Environmental Impacts Are Not Well Researched
Proposals to ban drift nets have been based mainly on the need to cut environmental impact associated with driftnets regardless of their scale. The environmental impact of small scale drift net fishing is not adequately researched primarily due to difficulty in monitoring such fleets. The assumption that a ban would improve environmental conditions remains unproven. Roy Smith from Defra believes the suppositions on drift nets are not entirely well-founded. Roy Smith argues that “for the waters around the United Kingdom (the North Sea and Western waters), the current EU cetacean bycatch regulations (812/2004) target controls on bottom sea gill and entanglement nets, which is where the related bycatch has been an issue, rather than drift nets per se.” He further states that a total ban of drift nets presupposes that the resultant move to alternative gears will present a more acceptable bycatch profile, which is not necessarily the case. UK fisheries cetacean bycatch monitoring and reporting suggest that a move away from driftnets to alternative trammel net fishing will not necessarily lower overall cetacean bycatch. UK fisheries for herring, bass, and salmon also do not have serious bycatch issues as exhibited in the Mediterranean and other fisheries that are of concern.
Loss Of Income
Drift net boats in the UK often have fish that are of better quality due to the limited amount of damage impacted on the catch when they are caught. The superior quality attracts a higher price premium, which goes to fishermen who are then better able to take care of their families.
An Economical Method Of Fishing
Drift nets are cost-effective and can target dispersed stocks in areas that would otherwise have been uneconomical using alternative methods of fishing. Drift nets, therefore, out-compete other fisheries in particular areas.
Fuel Efficiency And Lower Emissions
Drift net boats have low operating costs as a percentage of income earned compared to other fleets using alternative fishing methods. In the UK, fuel costs as a percentage of income for most vessels are about 12%. The lower costs are because the drift net boats do not have to tow large and fuel-costly nets. The low operating cost is only bettered by hook and line fishers. Drift net boats have lower carbon emissions, more economical engines that have a better carbon footprint compared to their larger counterparts. The sustainability credentials of drift net fishing have to be considered while factoring in greenhouse gas emissions and climate change.
Environmental Management Consideration
In the past, various management measures have been taken to minimize the impact of fisheries on the environment. Some of the measures that have been adopted include restricting the use of certain gear types, the introduction of quotas for non-target species, banning particular types of gear from a specific area, and the development of modified gear that minimizes impact on non-target species. The management measures under consideration should be considered within the management objectives. In the case of driftnets, several environmental objectives may be relevant. For example, controlling the impact or elimination of bycatch from a particular species could be considered appropriate environmental objectives.
About the Author
Benjamin Elisha Sawe holds a Bachelor of Arts in Economics and Statistics and an MBA in Strategic Management. He is a frequent World Atlas contributor.
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