It is well known that global pelagic and coastal fish stocks have plummeted since the development of more efficient fishing techniques, and the advance of larger vessels fishing for longer periods. Examples of this decline can be seen in the crash of the cod and herring fisheries, along with many others despite the "Management" methodolgy adopted to sustain and save these stocks. With this in mind, should we be looking to enlarge the global deep sea trawling industry?
There are several arguments for and against such a controversial issue; factors in favour of these techniques include the availability of new stocks, allowing potential relief of pressures on existing pelagic stocks, permitting many fishermen to maintain a livelihood and also allowing a continued provision of protein to millions of people. There are, however, two sides to each story. There has not been enough assessment of deep sea fish stocks to allow educated decisions to be made in an effort to utilise this resource sustainably. We also lack data on the recruitment and growth period of these deep sea stocks, but it is a general trend that deep sea organisms have slower growth periods due to the low supply of organic matter. This would suggest that deep sea stocks would have to be given longer recovery periods than other stock areas. How would this be controlled? How can we manage an environment we know so little about? Would it be economically viable to exploit these species if the vessels had to sit in port unable to trawl for months at a time?
As with any fishery there would be direct and indirect effects upon the ecosystem in question. Direct physical damage as a result of trawlers could include the impact on the benthos and possible sensitive species (e.g. lophelia corals), the effect upon the target stock as well as damage to other stocks through by-catch are all first level effects. Indirect effects include damage to the deep sea trophic structure with the removal of higher level organisms..
Considering all of this, is deep sea fishing a viable option? Certainly there should be more research conducted prior to any further movement towards this sector to ascertain whether it is sustainable and whether any inroads into this area of the fishing industry should be continued.
The question exists, just because we possess the technology to fish deeper, is it a practice we should pursue?