Water And Oceanography

The Effects of Overfishing on Coral Reefs

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"The Effects of Overfishing on Coral Reefs"
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Man is having a diminishing negative effect on sea life in and around the coral reefs in many ways such as global warming and increased carbon emissions through the burning of fossil fuels, ocean dumping of contaminating industry waste and upstream run-offs, harmful shipping and tourism by-products and more. Man is also further damaging the already stressed coral reefs by the deadly practice of overfishing worldwide.

As key high-demand members within the delicate ocean food chain are depleted from overfishing for commerce and pleasure it is upsetting the balance of prey and predator in the reefs. Many unwanted dolphins and turtles are also needlessly trapped in the nets and perish. This ocean species imbalance as a result of overfishing in the food chain not only shows below the ocean surface but also above in the sea bird population which feed on the fish in and around the reefs.

The domino effect of overfishing touches every organism, plant and life all important parts of symbiotic relationships in the coral reef food chain. The coral itself is the producer of the chain of food that sustains the herbivores and carnivores in the reef. Selective overfishing is causing an imbalance of certain fish and offers advantages and disadvantages to both prey and predator on either side of the selectively declined species. An overfishing of one species will lead to abundance in another and a continued ripple of declining predator and prey affected by the change. Equally devastating is the overfishing of an herbivorous fish and the resulting increase in algal growth which can bring about an overtaking abundance of sea grasses choking out life in the reef system.

Saltwater aquarium fishing to supply world hobbyist also has a large impact on the hundreds of species being chemically drugged for easier capture, plucked from the reefs and imported annually leaving behind reef damaging chemical kills. This unethical live fish trade has been shown to use cyanide in the catch having a devastating impact on both the people and the ocean species living in the tropics. By pouring poison onto the reefs and ripping apart the coral with crowbars the process is destroying the entire area. The developing countries and their village poverty have fisherman using methods damaging the coral reefs but in turn making a living in order to feed their families. Encouraging these people to catch fewer fish and use ethical methods will be difficult as long as the Asian and U.S. markets bring the need for this retail product.

Also alarmingly devastating is the explosive methods used where coral reefs are blasted with explosives so the stunned survivors are easier caught and in the process killing off the coral and completely destroying any ecosystem sustained within the reef leaving many homeless species open to prey and no hope of food or survival.

Efforts are being taken around the globe to bring an awareness and protection to this destruction within the reef life cycle. No fishing zones, conservation management and limitations are being developed but possibly not fast enough. If overfishing in the coral reefs remains mismanaged or unchecked humans will have a deadly impact on the ocean ecosystem and not only the coral reef food chain but also that of man.

More about this author: Michelle Greysen

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