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As human population grows, the demand and need for fish will grow alongside it (FAO, 2007). As such, despite developments in fishing technology, the demand and need for fish will almost certainly exceed sustainable levels. Aquaculture is poised to fill the gap between fish needs and sustainable fishing, and to be scalable to meet future demands (FAO, 2007).
Aquaculture is already economically viable, with with 40% of all food fish and 22% of all trade in fish already raised in aquaculture facilities, mostly from developing countries (Changing the face of the waters, 2007). However, some forms of aquaculture are far from sustainable.
The most pressing environmental issues are antibiotics used on fish leading to antibiotic-resistant strains of disease germs due to widespread use and the collapse of aquatic ecosystem ecosystems around aquaculture facilities collapsing. Some other issues that must be resolved are include the escape of genetically modified fish escaping into the wild , and the need to feed the fish in aquaculture facilities (Aquaculture: Fulfilling Its Promisefulfilling its promise, 2007). Our goal is to develop guidelines for an individual country to follow when creating an aquaculture industry , that would remove that is both free from as many environmental dangers as possible , while remaining and scalable to meet growing fish demand in the future in an economically viable way.
Since our goal for aquaculture is to partially replace Meeting fish demand through aquaculture will involve replacing the consumption of wild fish with that of farmed fish as a food source, we focused primarily on fish farming, rather than all forms of aquaculture. For the purposes of this plan, we looked at two general types of fish farming, : cage farming and intensive farming. The first type, cage farming, uses cages in large bodies of water, relinquishing control over water quality for a cheaper, simpler system. The second type, intensive, uses closed or nearly closed-loop water filtering systems, so that the fish do not interact with any natural environments.
Extensive Aquaculture
Cage farming has the virtue of being comparatively simple to set up and maintain , as because there is no need for advanced water quality control systems. However, the this reliance on nature for water management causes many greater environmental problems, notably the risk of algae blooms caused by the concentrated waste and nutrients. The concentrated nutrients cause the amount of algae to skyrocket, which then depletes all the resources and ruins water quality (Aquaculture: Fulfilling Its Promise, 2007). The level severity of these risks are very dependent on site selection and the staying within , whether the captive population is limited to the carrying capacity of the body of water, and the levels of pollution from industrial and other sources. Near-shore waters nearby sources such as industry. Ocean waters near the shore with good tidal flushing can be suitable, however are most suitable for this type of aquaculture, and more exposed sites and attention to cage density can prevent risks to the environment (C. Goudey, Personal Communicationpersonal communication, November 20, 2007). Other solutions we have found are either to Other strategies to lessen the risk of environmental damage use shellfish, sponges, or other filter feeders for local to improve water quality management (Shellfish used as a Fish Farm biofilter), or to make the cages mobile so waste does not concentrate in any one location (Model Tests and Operational Optimization of Self-Propelled Open-Ocean Fish Farm). By dispersing the waste and nutrients, it is much easier for the environment to absorb. (Shin, 2005). Also, it may be possible to use mobile cages to reduce the effects of unhealthy waste concentration (MIT Sea Grant, 1998). The first option would work well for countries where the right species are already native to the area, while the second option would allow landlocked nations or nations with little coastline a shot at chance to develop aquaculture, as the mobile cages can could be deployed in the open ocean, in international water. There remains the question of the economic feasibility of the mobile cages described in Model Tests and Operational Optimization of Self-Propelled Open-Ocean Fish Farm, especially in regards to developing nations. While we are not currently able to provide an answer, we believe that should sufficient commercial and governmental pressure develop, means of reducing the cost of mobile-cage aquaculture would arise. These two options should provide most nations a means of performing extensive aquaculture while preserving the environment.
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Aquaculture: Fulfilling Its Promise. (2007). In Encyclopædia Britannica. Retrieved November 25, 2007, from Encyclopædia Britannica Online: http://www.britannica.com/eb/article-92632
Dr Shin, P. K. S. (2005). Shellfish used as a Fish Farm fish farm biofilter. In Research Frontiers. Retrieved November 25, 2007, from http://www.ugc.edu.hk/rgc/rgcnews10/Pages/2b%20Biofilter-E.html
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