Effects that Aquaculture Can Have on Wild Fish Stocks - Assignment Example

1-Aquaculture can be viewed as a means of relieving pressure on wild fish stocks. Discuss the merits of this view in light of the known effects that aquaculture can have on wild fish stocks. a. Introduction The development of aquaculture has been considered by many as a support towards the existing wild fish stocks. In fact, it could be stated that the production rate of aquaculture is usually sufficient to cover the consumption needs around the world (at least at a significant degree). As a result fishing in the oceans can be reduced offering the appropriate chance to wild fish stocks to be increased. b. Main body In accordance with a series of statistics revealed in 1988 regarding the world fish production, in the particular year ‘the world fish production was reported at 98mmt, a figure that includes 14mmt from aquaculture and 84mmt from capture fishing; thus the aquaculture yield of 14mmt represents 19 percent of the total edible fish production in 1988’ (Commission on Engineering and Technical Systems, 1992). In accordance with the Commission on Life Sciences (1996, 80) ‘a substantial number of salmon populations are in some jeopardy’. Other wild fish stocks are also in danger. The use of aquaculture as a supportive tool towards the protection of wild fish stocks cannot be denied. On the other hand, in accordance with the study of Nolan et al. (2000, 1017) ‘many people believe that the growth of aquaculture relieves pressure on ocean fisheries, but the opposite is true for some types of aquaculture; farming carnivorous species requires large inputs of wild fish for feed; some aquaculture systems also reduce wild fish supplies through habitat modification, wild seedstock collection and other ecological impacts’. The above views are supported by the fact that ‘one of the most disturbing trends in aquaculture is the rapid expansion and intensification of shrimp and salmon farming and culture of other high-value carnivorous marine fish such as cod, seabass, and tuna; production of a single kilogram of these species typically uses two to five kilograms of wild-caught fish processed into fish meal and fish oil for feed’ (Nolan et al., 2000, 1019). In accordance with the above aquaculture can also have a negative impact on wild fish stocks. c. Conclusion The development of aquaculture in order to protect the wild fish stocks is proved to be a solution with limited effectiveness. More specifically, it is proved above that aquaculture can have both positive and negative effects on existing wild fish stocks. The effectiveness of aquaculture towards the limitation of pressure against the existing wild fish stocks depends on the policies applied by each state and the measures taken for the protection of wild fish stocks. 2- How can intensive and extensive aquaculture affect the genetic, species and ecosystem diversity of aquatic systems? Use examples to illustrate your points. a. Introduction One of the most significant issues that should be taken into account when referring to aquaculture is the fact that aquaculture can have a series of effects on genetic, species and ecosystem diversity of aquatic systems. These effects are differentiated in accordance with the practices applied in each particular unit (referring to establishments and places that participate in a specific aquaculture scheme). b. Main body It should be noticed that in accordance with the study of Naylor et al. (2000, 1019) ‘an estimated 8% of total aquatic primary production (137,000 Mt dry weight) is needed to sustain capture fisheries, seaweed collection and aquaculture; this proportion ranges from 2% in the open ocean to 24–35% in freshwater’. At a next level, is seems that other problems are related with the development of aquaculture internationally. In this context, it is mentioned that ‘the industrys existing problems with pollution, disease, drug use, and additives are troublesome and potentially dangerous; the future of the industry rests on improving production, decreasing environmental pollution, and making the product safer for human consumption’ (Perez, 2003, 43). The above issue has been also studied in its practical aspect. More specifically, Dempster et al. (2004, 1573) tried to measure the ‘environmental effect of coastal sea-cage fish farms on wild fish’ and found that ‘potential effects of large aggregations of wild fish in the immediate vicinity of fish farms include increased vulnerability to fishing and pathogen transfer between caged and wild fish’ (Dempster et al. 2004, 1573). It seems that aquaculture affects directly the genetic structure of species in all aquatic systems globally. c. Conclusion When referring to the effects of aquaculture on existing aquatic systems, we mean the short and the long term effects of the above activity on the development of marine species in all aquatic systems around the world. This development can be limited because of the negative effects of aquaculture on the environment (pollution), on the genetic structure of species (breed of species with different genetic characteristics than those of the wild stocks) or on the existing wild stocks globally (release into the oceans of genetically modified species or use of existing wild stocks for the breeding of species within the farms). 3- Consider an intensive aquaculture form of fin-fish farm in a marine inlet. Describe the possible changes you might expect in the physical, chemical and biological characteristics of the sediment as you move from the edge of the farm to a point several hundred metres down current. Assume that the farm discharges a significant organic and chemical load. a. Introduction The management of marine establishments (farms) used in aquaculture is a challenging task. Continuous controls should be made in order to ensure the protection of the environment from pollution. On the other hand, it is necessary to continuously review the methods applied throughout the farm – to check if they are in accordance with the standards imposed by the particular industry and if the quality of the food (and of any supplementary material used as a food) is at a high standard. b. Main body When developing a fin-fish farm it is necessary to follow the rules imposed by the local government regarding the management of waste involved. In fact, every government internationally publishes its own rules regarding the waste management of farms developed in aquaculture. We could refer as an example to the ‘Guidance Document for the British Columbia Finfish Aquaculture Waste Control Regulation’ published by the Government of British Columbia (Ministry of Environment) in 2003 (this is the most recent version of this guidance available to the public). In accordance with this guidance the following actions should take place regarding the physical, chemical and biological characteristics of the sediment of the particular finfish farm: ‘a) sulphide monitoring and conduct biological monitoring (this can take place periodically) and b) biological samples should be analyzed in accordance with the existing law’ (Guidance Document, pg. 6). On the other hand, it is noticed that ‘by locating fish and shellfish farms in areas where currents and water movement naturally sweep farm wastes away from sensitive or diverse ocean/freshwater floor environments, the potential effects of these operations are reduced’ (Fisheries and Oceans, Canada, aquaculture, 2007). In other words, the following issues should be taken into consideration regarding the waste management in a finfish farm: a) the area chosen for aquaculture should have the characteristics described above (physical factor), b) the water in the region should be appropriate for the specific species – a detailed analysis of the water would be required in advance (chemical factor) and c) all material produced should be checked and samples should be sent for analysis in accordance with existing laws – the food given to fish should be also examined as of its appropriateness (biological factor). c. Conclusion The development of any finfish farm around the world requires the application of certain rules and principles (stated by the local government or the international organizations whenever they have such a right to intervene). Only if these rules are applied the harvest involved would be of high quality while any damage to the physical environment will be avoided. 4- Contrast intensive and extensive aquaculture and then, using examples, go on to explain which of the differences could result in differences in (a) the types and (b) the magnitude of environmental impacts associated with each form of aquaculture. a. Introduction The systems applied in aquaculture are differentiated mostly because the materials/ establishments available in each particular region are different. More specifically, there are regions in which the technology available for aquaculture is high. In this case, different systems of aquaculture are applied than in areas where the equipment available for the particular industrial sector is limited (see Figure 1, Appendix). In this context, aquaculture currently is developed around the world using two main systems: the intensive and the extensive ones. The particular characteristics of each of these systems and their benefits are being analyzed below. b. Main body In accordance with a description presented by the Ireland Water Resources and Aquaculture Service [1] ‘extensive farming usually involves unsophisticated technology, relies on natural food and has a low input to output ratio; usually only a part of the life cycle is controlled, for example extensively operated fish ponds often rely on the supply of fish juveniles from the wild, and production inputs, in the form of feed and fertilizers, are provided only occasionally, if at all’(Figure 1, Appendix). In other words, extensive units are characterized by the lack of advanced technology; on the contrary traditional methods of aquaculture are applied. As for the intensive systems, these have a significant benefit which is their production capacity. Indeed, in accordance with a report published by the Ireland Water Resources and Aquaculture Service [1] the high level of production of intensive systems is achieved ‘through higher levels of technology and a greater degree of management while fish or other aquatic organisms are often reared from egg to adult stage within the culture facilities, stocked at higher densities, and in smaller, well-designed facilities’ (Figure 2, Appendix). The differences between the two systems can be made clear through the examples presented in the Appendix section. c. Conclusion In accordance with the above the superiority of the intensive systems over the extensive ones is clear. Intensive systems can respond more effectively to excess demand while extensive systems can be adapted better to the traditional methods of aquaculture used by local population in communities around the world. 5-The EPA (Environmental Protection Authority) is aware of plans for four separate aquaculture proposals (2 intensive and 2 extensive) in a coastal archipelago that includes a marine park and existing capture fisheries for anchovie and bottom-dwelling prize fish such as snapper. They have elected to conduct a strategic environmental impact assessment and are attempting to set the terms of reference for the proponents. You are required to provide them with guidance on the range of issues they should ask the proponent to address along with an explanation of the relevance of each issue and a justified priority ranking of the importance of each issue. a. Introduction In order to establish and develop a marine park, it is necessary primarily to conduct the relevant strategic environmental impact assessment that will reveal all possible problems related with the operation of this unit as well as the solutions available for the successful resolution of all these issues effectively without harming the environment. b. Main body In order to effectively apply the Strategic Environmental Assessment in the particular marine unit, we should primarily refer to its characteristics. In this context, it is noticed by Finnveden et al. (2003, 91) that the ‘Strategic Environmental Assessment (SEA) is a procedural tool and within the framework of SEA, several different types of analytical tools can be used in the assessment (like the Life Cycle Assessment, Risk Assessment, Economic Valuation and Multi-Attribute Approaches)’. The particular stages of SEA applicable in the particular case could be described as follows: a) Habitat mapping; Risk analysis; and c) Sensitivity mapping (WWF-UK, 2007). Other activities maybe also required in order to ensure the sustainability of the unit regarding its physical environment. In accordance with the above, regarding the intensive systems the following issues should be addressed (ranked by importance): a) appropriately structuring of the units so that the pollution of the environment is avoided, b) efficiency of the units in terms of the needs of local population (the size of these units should be in accordance with the needs in the specific food so that the excess of specific limits on the population of species that are ‘cultivated’ to be eliminated. In the case of the intensive units the following issues should be addressed (also ranked by their importance): a) needs of the physical environment in the specific region, b) availability of the region required for the appropriate development of the intensive system, c) monitoring of the unit’s operation on a continuous basis, d) construction of the appropriate establishments that would remove waste without polluting (at least the pollution should be low) the physical environment. c. Conclusion The development of intensive or extensive marine systems in a particular aquaculture unit can depend on many parameters (indicatively mentioned above). The main criterion for choosing the system applied on a relevant unit should be the protection of the environment; at a next level the local needs should be measured in order for the system that is going to be implemented to be able to respond to the needs of local population. References Committee on Assessment of Technology and Opportunities for Marine Aquaculture in the United States, Marine Board, Commission on Engineering and Technical Systems, National Research Council (1992) Marine Aquaculture: Opportunities for Growth. Committee on Protection and Management of Pacific Northwest Anadromous Salmonids, National Research Council (1996) Upstream: Salmon and Society in the Pacific Northwest Dempster, T., Jerez, P., Sempere, J., Kingsford, M. (2004) Extensive Aggregations of Wild Fish at Coastal Sea-Cage Fish Farms. Hydrobiologia, 525 (1-3): 245-248 Finnveden, G., Nilsson, M., Johansson, J., Persson, A., Moberg, A., Carlsson, T. (2003) Strategic environmental assessment methodologies—applications within the energy sector. Environmental Impact Assessment Review, 23(1): 91-123 Fisheries and Oceans, Canada, aquaculture (2007), Waste Management, [online], available at http://www.dfo-mpo.gc.ca/aquaculture/sheet_feuillet/waste_e.htm Guidance Document for the British Columbia Finfish Aquaculture Waste Control Regulation (2007), [online], available at http://www.env.gov.bc.ca/epd/epdpa/industrial_waste/agriculture/agri_fishf.htm Ireland Water Resources and Aquaculture Service (2000), [online], available at ftp://ftp.fao.org/docrep/fao/003/x7156e/x7156e00.pdf Ling, B., Leung, P., Shang, Y. (1999) Comparing Asian shrimp farming: the domestic resource cost approach. Aquaculture, 175(1-2): 31-48 Naylor, R., Goldburg, R., Primavera, J., Kautsky, N., Beveridge, M. (2000) Effects of aquaculture on world fish supplies. Nature, 405: 1017-1024, [online], available at http://www.nature.com/nature/journal/v405/n6790/full/4051017a0.html;jsessionid=D1B1D0A297E88AA860D73E3C8D750E32 Perez, J. (2003) Aquaculture and the Environment: the Risks and Rewards. Journal of Agricultural and Food Information, 5(1): 43-50 The Wildlife Trusts Joint Marine Program (WWF – UK), 2007, available at http://www.wwf.org.uk/filelibrary/pdf/sea.pdf Appendix Figure 1 – Extensive aquaculture system (source: http://www.fao.org/docrep/003/x7156e/x7156e02.htm) Figure 2 – Intensive Farming (source: http://www.fao.org/docrep/003/x7156e/x7156e02.htm) Read More