Ocean Fishers Tuna-Dolphin Issue in the Pacific Ocean - Research Paper Example

 Abstract The issue of tuna dolphin is as controversial as emotional. Besides the problem being a recent one, emerging with the development of purse seine fishing methods in 1960s; it is still incompletely understood. It involves the complex and poorly understood facets of the marine ecosystem, further complicated by the economic significance of the issue. The international nature of the problem contributed to political intricacies and legal complications. International issues require international cooperation and cumulative effort. Several advances have been recently made to ensure the safety of the dolphins though the alternatives employed are not without their own sets of adverse impacts. The current projects aims to develop an understanding of the ecological and ethical issues relevant to the tuna dolphin controversy, evaluate the alternatives and propose possible solutions. DELIBERATION ON THE ETHICS OF DOLPHIN BY CATCH IN TUNA FISHING REQUIRES MUCH MORE RESEARCH THAN IS CURRENTLY AVAILABLE INTRODUCTION Dependence of man on plants and animals for his dietary requirements renders human interference with the natural processes unavoidable. Interference, however; is not the same as damage. While certain interactions among living organisms are essential for ecological homeostasis, certain others affect homeostasis adversely. Human exploitation of natural ecosystems must further involve ethical consideration since man is capable of modifying nature to meet his requirements, to use and develop minimal invasive alternative technologies of exploitation; or to forgo consideration for personal satisfaction and greed. Besides, man is also capable of moral discretion. Brennan & Lo in the article on Environmental Ethics mention that a combination of the two aspects is environmental ethics and it deals with the moral issues involved in the interaction of man with his environment. Food harvesting from marine ecosystem has been one of the most extensively explored and equally controversial issues for the natural scientists, environmentalists and policy makers. One of the controversies involves the methodology used for fishing of tuna leading to the killing of dolphins present in the vicinity. This has led to a sharp decline in the population of dolphins. Current estimates of abundance provided by Gerrodette & Forcada (1) are 640,000 and 450,000 of northeastern offshore spotted dolphins and eastern spinner dolphins respectively. Several disagreements complicate the international opinion and render an in depth discussion of the issue imperative. The current project aims to study the environmental implications and ethical issues involved in the tuna-dolphin issue in the Pacific Ocean by exploring the background, international opinion and policies relevant to the issue. Background: Emergence of the issue Yellowfin tuna (Thunnus albacores) fishing in eastern Pacific Ocean is a significant economic activity responsible for 25% of world yield of yellowfin tuna. The activity commenced in early twentieth century off the southern Californian and Baja California coast, moving seaward and eastward to meet the increasing demands. By the mid-twentieth century the areas covered by U.S. baitboats for tuna fishing extended several miles offshore from the U.S.-Mexican border using the techniques of school-fishing or log fishing. The scenario underwent a revolutionary change doubling the catch amount during this period with the development of synthetic fiber purse-seine nets and hydraulic power blocks for retrieval of nets (Matsumoto). This technique was based on the fact that tuna accumulate below herds of certain species of dolphins specifically spotted dolphin (Stenella attenuate), spinner dolphin (S. longirostris), the common dolphin (Delphnus delphis); imparting the name dolphin fishing to the technique. Dolphins are air breathing mammals and swim closer to surface. Hence they are easier to spot. Yellowfin tuna aggregates increase in size due to growth of individual fishes after hatching, but there is a simultaneous loss due to high mortality rates. The stage with maximum biomass due to the mortality and growth factors at par yields largest productivity for the fishers. This is approximately the stage during which the yellowfin tuna are found to be associated with the dolphins (Hall, 3). During dolphin fishing the net is spread around such herds of dolphins to catch the tuna underneath, the dolphins are then released and the tuna collected. Like every technological application there are certain negative implications of this development as well; the major being overexploitation of yellowfin and simultaneous killing of dolphins. Dolphin mortality is high due to the entanglement and suffocation of the dolphins trapped in the purse-seine nets. The problem was first reported in 1968 by a scientist of the National Marine Fisheries Service (NMFS) (National Research Council) and termed as ‘tuna dolphin issue’ by Gerrodettte (1269). Regulations and Agreements Marine Mammal Protection Act (MMPA), 1972 As a consequence of the first reports of dolphin mortality as by-catch during tuna fishing by U.S. vessels, the Marine Mammal Protection Act (MMPA) of 1972 was passed directing the management of optimum sustainable population of marine mammals during their exploitation. With respect to the incidental killing of dolphins it states that ‘the immediate goal that the incidental kill or incidental serious injury of marine mammals permitted in the course of commercial fishing operations be reduced to insignificant levels approaching a zero mortality and serious injury rate’. The levels of dolphin mortality estimated by NMFS for the period spanning 1972 to 1976, i.e. after the passing of MMPA act, was found to decrease to one third of the levels reported for period preceding the act. As a consequence general permits allowing dolphin fishing of tuna was issued by U.S. secretary of commerce in October 1974. The permit was opposed by several environmentalists and organizations, leading to the amendment of the permit in 1976 limiting the permissible mortality levels for U.S. vessels to 78,000 dolphins annually (Joseph, 4). Though the dolphin mortality further fell to levels one third of those reported for 1972-1976 during the period from 1976 to 1980s; but the ethical and environmental concerns related to incidental dolphin mortality still remain controversial. The two major issues are whether it is ethical to allow dolphin killing for tuna fishing, and if allowed what should be the permissible limits for dolphin mortality (Joseph, 4). Further amendments in 1981 and 1984 altered the permissible limits of dolphin mortality to 20,500 for the U.S. vessels. For the foreign fleets too, the 1984 amendment imposed similar restrictions. There was a simultaneous sharp decline in number of U.S. vessels for tuna fishing in eastern Pacific Ocean; from pre-1960 levels of 85% to a mere 35% by 1984. The major causes of this decline were a shift of U.S. vessels to the western Pacific Ocean, sale of U.S. fleets to emerging and rapidly growing private companies from the Latin American countries. As a direct consequence of this dolphin mortality again began to rise by late 1970s making it an international issue rather than the concern of the U.S. exclusively (Hall, 4). Role of Inter-American Tropical Tuna Commission (IATTC) To address this problem a program was initiated by the Inter-American Tropical Tuna Commission (IATTC) in 1976. The objectives of this program were to ensure high levels of tuna production while simultaneously avoiding dolphins’ killing and ensuring that the population levels of the dolphins are maintained sufficiently for their survival. During the observations conducted as a part of this initiative a mortality of 133,000 and 100,000 dolphins was reported in the years 1986 and 1987 respectively; with further lower levels of 2600 reported in 1996 (Hall, 1998). Further amendments in the MMPA act in 1988 allowed exports from the nations with regulatory policies equivalent to those of U.S.; and permissible mortality limits also similar to the U.S. levels (Hall, 8). Both the U.S. fish processing units and the Congress finally realized that irrespective of the losses incurred by the fishery industry, the concerns for ecological imbalance, and the sensitivity of the other nations to the issue; it is unethical to allow dolphin by-catch. Hence tuna canning companies, following the initiative of the largest of U.S. tuna canning company on April 12, 1990; decided to purchase tuna caught exclusively by vessels with IATTC certification ensuring they were not responsible for dolphin killing during the process. However; this embargo only led to marginal decline in dolphin mortality due to the transfer of the catch to European countries; the second largest markets of tuna next to U.S. The embargoes were further challenged by Mexico in front of the dispute settlement panel of the council of the General Agreement on Trade and Tariffs (GATT) (Joseph, 10). La Jolla Agreement The international concern over Dolphin protection led to the establishment of The International Dolphin Conservation Program in 1992 (La Jolla agreement), at the initiative of IATTC. It involved 10 countries including Mexico. It aimed to reduce dolphin mortality levels to 5000 by 1999. In U.S. the International Dolphin Conservation act was passed which implemented a 5 year moratorium on tuna fishing through purse-seine net commencing March 1, 1994. The declaration of Panama in 1995 next resulted in lifting of U.S. embargo allowing import of tunas from countries adhering to the agreement (Scott, 16). Present Situation in U.S. Gerrodette & Forcada (2), mention that on December, 21, 2002, the U.S. secretary of commerce declared tuna dolphin fishery to have an insignificant adverse impact on dolphin abundance. The same was challenged, considered scientific and hence, invalidated in U.S. courts in August, 2004. Environmental Impact Environmental impacts of tuna dolphin problems concern two major aspects; one with respect to tuna population and the other for dolphin population and survival. Though both are interrelated, yet need individual attention to enable a balanced approach. In either case we need to ascertain the existing levels of populations, their current trends, levels of mortality and risk to survival, and trends other than those affected by purse seine fishing. Mortality Rate and Potential Biological Removal In order to ascertain the safe or permissible levels of mortality, ‘potential biological removal’ or PBR is being developed. Conformation to the estimated PBR levels would ensure that incidental mortality of dolphins is within the limits of sustainability and thus would have lower negative ecological impacts. The mortality levels achieved by 1996 indicate that except for the spotted dolphins the PBR for the rest is reasonable higher than the mortality estimates. However; even at the zero mortality rates achieved, the pre-exploitation stage of population cannot be achieved yet, unless the mortality rates are maintained for several coming years. Further factors such as loss in population, ecological damages as a consequence of the loss, and probabilities of further negative impacts may delay the process (Hall, 19). The trophic relationships between tuna and dolphins and the impact of fluctuating rates of dolphin mortality over the century as a consequence of tuna fishing are not completely understood. However, besides the direct negative impact on population; the killing of dolphin as by catch has several other associated and potential adverse effects on dolphin population. The disruption of social structure of dolphins renders them vulnerable to predators further contributing to decline in population. Frequent injuries and exposure to stress is expected to reduce survival, reproduction and growth rates. Besides injuries to adult population, incidences of fetal fatality are also increased during chases accompanying tuna fishing. Though the extent of none of these dangers can be estimated, yet indirect evidences for these are available from frequent reporting of sharks close to the purse seine nets. Incidences of abortions have also been reported. But the impact of long term injuries and stress related effects are difficult to assess or gather evidences for (Hall, 19). Dolphin Fishing vs. Log Fishing: The Controversy Another aspect of the problem is that though dolphin mortality is high in dolphin fishing; in terms of number of dolphins killed per ton of tuna caught, it is lower in dolphin fishing compared to log fishing. Further floating objects trap large number and varieties of marine animals; thus by catch in general is much higher in log fishing compared to dolphin fishing (Hall et al.). Many species of sharks, rays and endangered species of sea turtles get trapped along with tuna in log fishing nets. Tuna discard rates due to the organisms being too small or damaged rendering them unfit for sale is much higher (up to 15 times) in log fishing (Scott, 16). Another issue of concern associated with log fishing is that the tuna so caught are young. Besides being of lesser economic value, they have yet to reach the stage of reproduction. Catching them can severely lower the population growth of the tuna, compared to catching those that have already reproduced (Scott, 18). Thus the complicated nature of the issue renders it impossible to evaluate the situation in terms of dolphin population only. Impacts of killing of dolphin needs to counterbalanced with the killing of many species in larger quantities from ecological as well as ethical point of view. Ethical Considerations Trophic structure in nature is essentially a chain of eating and being eaten. Food harvest by man therefore would involve killing of animals. The question related to ethical consideration therefore, primarily centers on limits and alternatives. Based on the premise that man can achieve equivalent benefits casing no or lesser harm to the dolphins, that dolphins are subjected to sufferings and become simply means to achievement of ends that do not involve them, that they are treated as property rather than individuals; the process is unethical (White, 7). While the mortality of dolphins according to latest reports is well below survival limits in case of purse seine fishing; the same cannot be claimed with certainty with regard to log fishing; the alternative recommended by environmentalists. Neither can generalizations be made with respect to the species killed as by catch in log fishing nor can their relative population be estimated. It is however certain that mortality involved is much higher than in purse seine fishing. Thus using log fishing as an alternative to seine purse would be allowing one problem to aggravate in order to solve another (Hall, 12). Besides allowing other species to be killed to save dolphins (which of course have come to achieve more attention due to their recreational value and the controversies attached to dolphin fishing); is neither ecologically, nor ethically sound practice. Hence while proposing log fishing as an alternative to purse seine or while discussing the negative impacts of latter; the disadvantages of former must also be addressed. Possible Solutions Several methods have been proposed as possible solutions to overcome tuna dolphin issue related problems. Besides the log fishing with its own set of disadvantages already discussed; pole and line fishing, loglines, gill nets are some of the common alternatives explored. But none of these has been found to exhibit advantages compared to purse seine fishing. The solution to these problems can be sought with the aid of researches that can enable development of alternative technologies. Purse seine technology has proved to be economically most favorable and hence researches need to be directed to deal with the issue of lowering dolphin mortality. There are three aspects that are being explored with respect to this: locating schools not associated with dolphins but comprising of large numbers of large tuna; developing means to attract tuna prior to capturing them; and finally devising methods to enable driving them away from dolphin prior to casting the nets. To address the first issue, experiments are being done with laser, acoustics and radar; though they still remain inconclusive. To attract the tuna fish attracting devices (FADs) are being experimented with in probable or pre-reported areas of availability of schools. Again these devices too need further research. In order to separate the tuna from the dolphins, techniques such as use of chemical or sound to drive away the dolphins as well as methods to attract or repel tunas or dolphins have been proposed. In order to obtain conclusive evidence for the efficacy of either of these methods, further researches are required to build an understanding of the social structure and behavior of both of these groups of organisms (Hall, 16). REFERENCES Read More