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Sharks

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Shark Killing and the Ecosystem
Introduction
Sharks are fascinating creatures that come in all sizes and live in water all over the world. Arguably, these creatures play a very imperative responsibility in the ocean that a fish cannot. Apparently, sharks are the top food providers in the ocean almost in every part of the world. In this case, they assist in keeping the inhabitants of other fish species healthy and in suitable proportion for their ecosystem. However, shark population faces the threat of extinction in almost all parts of the world due to overfishing. Fishers us a technique called Bycatch, a process in which marine mammals or species of fish are unintentionally, caught while fishing for a specific target. Irrespective of the initiatives and laws put in place for overfishing, fishers have continued to hunt sharks for the fin soup, which is in high demand than their meat. On the other hand shark cartilage and shark liver oil are sold as cures for the hosts of aliments. Due to this disparity between meat and fins, it has led to a horrific practice of shark fining. As a result, there is need to create awareness on the importance of sharks in all parts of the world in order to save ocean ecosystem from extinction.
Catching Techniques Many fishing techniques and gear are no selective and result in catching and discarding millions of marine life that is not always the target species. Most of the fishing methods like the long line typically are used to catch tuna. However, this fishing line has thousands of hooks that indiscriminately catch everything that comes to eat the bait including sea birds and sharks. As such, this method of fishing endangers those species that are not in target and end up putting the whole ocean and ecosystem at risk. Of late, shark by catch method is considered a nuisance and that sharks are cut loose and disposed of overboard and sometimes still alive. Due to this, it is estimated that 50 million sharks are caught as bycatch in commercial fisheries in every year in many parts of the world. However, leaders have demonstrated the increased reduction of sharks by the current methods of fishing (Turner, 2013, p.38). In addition, these methods result in higher yields of target fish and this help them to save money for the crew.
Fear and Fishing One of the leading reasons for shark hunting is to destroy them. This is because many people fear the ocean when these creatures are present. There is no love lost between sharks and man in many areas. Due to the increase in commercial fishing, sharks killing tend to increase in order to pave way for fishing. Fishermen argue that sharks prevent them from fishing hence risk their source of earning a living (Burnham, 2000, p.22). As such, they believe that by killing sharks will make the ocean safe for everyone. Despite that there is lack of enough evidence, people believe that sharks are man eating creatures (Strong, 2003, p.33). This fear prevents them from swimming and sailing on boats for pleasure. As a result, they end up destroying them in order to attract tourist who travel from different regions in search of places to swim and spent their time. However, most of countries make a lot of revenue from tourists who come for swimming. This activity endangers sharks live in such places.
Recreational Fishing There has been a lot of attention put in place on the impact of commercial fishing on shark populations and this is well defensible considering the sheer scale of fishing. Consequently, the overall impact of recreational fishing on shark population is difficult to detect. This recreational fishing is common in places like United States, Australia, New Zealand, among other parts of the world (Crawfor, 2008, p.152). Through this recreational fishing, several species are on the target and these include the blue sharks, shortfin mako, and thresher sharks. In other parts of the word, recreational shark fishermen do practice catch and kill techniques just for fishing records and obtain trophies for the activity, despite that most of the fishermen are responsible stewards of the sea, some of them d heavily target sharks and may have an observable on the species such as bull sharks (Cunningham-Day, 2001). The most important aspect of this fishing is for the people to know how to catch shark. In addition, fishermen and tournaments are changing in catch and release technique and when these sharks are caught, they are stressed and when released may not survive (Baum, 2003, p.390). Available at: http://www.environmentalgraffiti.com/animals/news-sharks-rapid-decline-due-desire-shark-fins-0 [Accessed 12 November 2013]
The Significance of Shark Species in the Ecosystem Sharks serve a very vital role in ecosystem since they have developed in a tight-dependency with the ecosystem. In the ocean, they observe and prey on the old, sick and much slower species of fishes that do not play an important part in the growth of the ecosystem (Crawfor, 2008, p.150). As such, they cushion the marine size by preying on the species that do not harm the ecosystem by becoming populous. However, ocean ecosystem has of intricate food webs and sharks are the top of these food webs that are preferred by scientists (Fison, 2010, p.48). This means that they are very important in the ocean and removing them from the ocean means that the whole ecosystem is destroyed. Due to this ground, the panorama of the food chain without predators may result to the end of the procession for many more important species (Miller, 2007). Scientists argue that depletion of shark species in the ocean results in loss of commercially essential species in the food chain. Most species of fish lost because of this depletion include tuna, which help to sustain the healthiness of coral reefs (Kyne, 2009, p.100). Available at: https://www.sharksavers.org/en/education/the-value-of-sharks/sharks-role-in-the-ocean/ [Accessed 12 November 2013] Through feeding of the sick and dead carcasses, they help scavenge the sea floor and help prevent the spread of diseases in the ocean. For this reason, they play a significant role in keeping the ocean healthy. Some diseases break from the dead species and may be devastating to the other living species in ecosystem and preying on they as well as the weak ones upholds the gene band of the prey species. Apparently, most of the healthy species reproduce in greater numbers and this result in large number of the healthiest fish (Osch, 2012, p.430). This is very important in growing and keeping the ecosystem in future. In addition, sharks play another role in regulating the behavior of the prey and avert them from over feeding important habitats. This is done through their intimidation factor and may act and have more impact on the ecosystem more than what sharks eat. An example is the presence of turtles in the sea, which do not overgraze in one are in the presence of tiger turtles (Burnham, 2000, p.21).
Liver Oil Fishery trade in shark liver oil called Squalene started because the compound was used as a machine lubricant that was later replaced by synthetics. Today, squalene is marketed as an expensive ingredient in cosmetics and lotions and is sold in the form of a pill as health supplement. Most of the fisheries usually target deeper oceans to locate sharks with larger liver that constitute up to 30 percent of their body weight. Most of these deepwater sharks are more vulnerable to over exploitation because of their low reproduction potential(Camhi, Pikitch and Babcock, 2008). The liver oil trade caused the collapse of the gulper shark fishery in Maldives only 20 years after it began (Maccormick, 2003, p-141). In parts like Portugal, the Portuguese shark is mostly targeted for their Squalene resulting in a declining overall abundance (Maccormick, 2003, p.141). This Squalene is made up of hydrocarbon compound and can be extracted other sources such as palm oil, and can be farmed in a more sustainable method and this helps in the reduction of shark depletion in the deep sea. Irrespective of the alternative source of squalene from palm oil, fisheries continue to hunt sharks because they have learned the techniques of catching them and are easily found than the palm oil. As a result, they end up neglecting the alternative and continue to deplete sharks that help to maintain the ecosystem favorable for other healthy species.
Habitat Loss, Pollution and Environmental Degradation Coastal development has significantly increased in the recent years and has altered habitats due to the increased pollution and this has resulted in the general environmental degradation in many countries. Observably, many shark species use inshore coastal and estuarine habitats as safe place for finding food, giving birth and protecting their young ones from predators. This means that they are at a risk of being negatively affected by the changes in the habitat (Watts, 1999, p.31). An example is dredging of Bahamas that resulted in 25 percent decline in juvenile lemon shark survival. These juvenile sharks are known to be trapped by warm water falls power plants found in United States of America and this make sharks no to migrate if this water does not flow (Maccormick, 2003, p.142).. In the other hand, some sharks may succumb from thermal shock that may cause them to cease seasonal migration. Arguably, sharks are very prone to pollution and environment contamination. This pollution in the ocean results from disposal of waste material from the land and directly deposited to the sea. Consequently, shark become proximity to chemicals discharged from industries that increase pollution to the sea hence risking ocean ecosystem decline in future (Jackson, 2001, p.630).
Conclusion
Quite evidently, shark species and the whole of ocean ecosystem are endangered due to overfishing and lack of appropriate conservation mechanism. Irrespective of the measures put in place to help conserve ocean ecosystem, fisheries have neglected the orders and continued to exploit ocean in such of fish fins and other essential materials from the ocean. Some other fisheries kill sharks in order to make the ocean safe while others hunt them in order to create costal harbors for making revenue. However, studies reveal that shark species are very essential in maintaining a healthy ecosystem by preying on sick and weak species in the ocean. This helps to create a healthy habitat for the healthy fish species that reproduce more health species. On the other hand, when shark species are depleted through bycatch method, it means that the habitat is at the risk of declining due spread of diseases. In the future, the whole ecosystem is no more due to overfishing and lack of better protective measures. Bibliography
Burnham, B. 2000. The Tiger Shark. New York, Rosen Pub. Group's PowerKids Press.
CrawforD, D. 2008. Shark. London, Reaktion Books.
Fison, J. E. 2010. Shark frenzy! Ormond, Vic, Hybrid Publishers. [Available at]: http://www.contentreserve.com/TitleInfo.asp?ID={9442E0F1-3183-4900-A7E1-B348AB09726B}&Format=410.[Accessed 11 Nov 2013]
Maccormick, A. 2003. Shark Attacks. London, Robinson.
Sharksavers.org. 2013. Shark Savers : Sharks' Role in the Ocean. [online] Available at: https://www.sharksavers.org/en/education/the-value-of-sharks/sharks-role-in-the-ocean/ [Accessed: 12 Nov 2013].
Environmentalgraffiti.com. 2013. Why Overfishing for Sharks is Destroying the Ocean's Ecosystem. [online] Available at: http://www.environmentalgraffiti.com/animals/news-sharks-rapid-decline-due-desire-shark-fins-0 [Accessed: 12 Nov 2013].
Camhi, M., Pikitch, E. and Babcock, E. 2008. Sharks of the open ocean. Oxford: Blackwell Science.
Miller, G. 2007. Essentials of Ecology. Australia: Thomson, Brooks/Cole.
Cunningham-Day, R. 2001. Sharks in Danger. Parkland, Fla.: Universal.
SimpfendorfeR, C.A. & Kyne, P.M. 2009, "Limited Potential to Recover from Overfishing Raises Concerns for Deep-Sea Sharks, Rays And Chimaeras", Environmental Conservation, 36 (2), pp. 97-103.
Van Osch, S. 2012, "Save Our Sharks: Using International Fisheries Law Within Regional Fisheries Management Organizations To Improve Shark Conservation", Michigan Journal of International Law, 33 (2), pp. 383-431.
Baum, J.K., Myers, R.A., Kehler, D.G., Worm, B. & al, e. 2003, "Collapse and Conservation of Shark Populations in the Northwest Atlantic", Science, 299, (5605), pp. 389-392.
Jackson, J.B.C., Kirby, M.X., Berger, W.H., Bjorndal, K.A. & al, e. 2001, "Historical Overfishing and the Recent Collapse of Coastal Ecosystems", Science, 293 (5530), pp. 629-637.
Watts, S. 1999, "Saving Sharks from the Jaws of Greed", The Animals' Agenda, 19 (5),
Strong, M. 2003. Shark!: The Truth Behind The Terror. Bloomington, Minn, Red Brick Learning.
Turner, P. S. 2013. The dolphins of Shark Bay.

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