Entanglement in fishing gearBy now, nearly everyone has heard of whales dying entangled in fishing gear. But, did you know that in certain cases the problem is so serious that it is endangering entire populations? The following are several examples of this type of incident from around the world. Entanglement is a major problem for which there is still no solution. A species of porpoise endemic to the Gulf of California, the vaquita, has been reduced to just a few hundred animals. It is estimated that between 30 and 40 vaquitas die each year in Mexican gillnets and shrimp trawlers. Although the fate of the vaquita is quite alarming, it is difficult to impose drastic solutions to the problem of fishing related deaths. Of course it is unthinkable that Mexico demand that the fishermen, who are struggling for their survival and that of their families, refrain from fishing. A glimmer of hope comes from the fact that the Mexican government recognizes that the fate of the vaquita is a subject of international concern. It is ready to accept financial and technical assistance in an attempt to find solutions to this problem, without overlooking the needs of its fishermen. Small coastal cetaceans, like the vaquita, are generally susceptible to entanglement either because the fish taken attract them, or because they are not able to identify the danger represented by the nets. Markets have been known to develop for cetacean meat based on entanglement. Examples of this can be found in Peru, Sri Lanka and the Philippines where fishermen sell the small cetaceans that get caught in their nets. As these practices are poorly, or not at all regulated, and they sometimes turn into a hunt aimed specifically at dolphins or porpoises. Without adequate controls these hunts could translate into a real threat for certain populations of cetaceans. Even though member countries do not consider the management and protection of small cetaceans to be the responsibility of the IWC (International Whaling Commission), an IWC committee is closely monitoring this situation. As is clearly demonstrated in the case of the North Atlantic right whale, even the great whales are not safe from entanglement. By the end of the nineteenth century, this species was nearly hunted to extinction. Despite having been protected for several decades now, far from making a comeback, the right whale is still endangered. There are only around 300 North Atlantic right whales left, and a third of all deaths within this population are attributable to ship collisions and entanglement in fishing gear. Steps have been taken to try to lower the risk of ship collisions and entanglement, but the whales continue to perish. Three privately funded groups that have been working for years for the protection of right whales have gone so far as to launch a contest to try to come up with new ideas. Little is known about the amplitude of the problem in the St. Lawrence. At the height of the cod fishery around Newfoundland, the entanglement of humpback whales was a serious problem. This situation led Jon Lien to put together a team of specialists that has been freeing trapped whales since 1978 in collaboration with fishermen. Not much is known about the real impact of entanglement on the other species that frequent the St. Lawrence. Yet, every year, minke whales, humpback whales and even blue whales trapped in fishing gear are reported to the Quebec Marine Mammal Emergency Response Network. Ideally, it would be best to avert all entanglement, but it’s not quite that easy… In the Gulf of Maine, for example, harbour porpoises die each year by the thousands in fish nets, however not one of the solutions tested to date has resulted in significant reduction of the mortality rate. In order to scare off porpoises, "pingers", or acoustic alarms, are placed on nets. The success of this technique remains ambiguous as they seem to work in some cases, but not in others. The same conclusion, or lack of conclusion, can be drawn for time/area closures to reduce bycatches of harbour porpoises. What is even more worrisome is that the context of the harbour porpoises is about as good as it gets for finding a solution: the American law is severe when it comes to the protection of marine mammals and teams consisting of scientists, fishermen and other concerned parties have been working hard to reduce entanglement for several years already. Obviously, the problem is a very complex one. Hopefully, the creativity and perseverance applied to the case of harbour porpoises in the Gulf of Maine will help solve other cases of entanglement elsewhere in the world. Entanglement is but one example of the conflict that exists between our use of the ocean’s resources and marine mammal use of those same resources. From the perspective of the fishing industry, marine mammals are often viewed as competitors to be eliminated or, at the very least, controlled. The various special interest groups involved must therefore continue to exchange scientific information, practical experiences and opinions in order to share the marine resources in such a way as to contribute to the conservation of the ecological wealth and integrity of the oceans. I want to know more Center for Coastal Studies Site, a group in charge of a whale disentanglement team report. |