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Jellyfish Benefiting from Climate Change
At an increasing rate, the dangers of climate change are being discussed. Higher temperatures will lead to melting ice caps and higher sea levels that will threaten the livelihood of many of the world's species, not to mention food resources and highly populated coastal cities. In short, global warming puts the entire Earth in danger. Though this may seem like a scenario where there are no winners, scientists are suggesting that the opportunistic jelly fish may counter this argument. According to a variety of recent studies and observations, the jellyfish and its many relatives are greatly benefiting from higher water temperatures caused by climate change.
In a variety of different regions and countries there is a similar phenomenon: jellyfish are taking over vast amounts of coastal waters, beaches and various sections of open water, where they previously did not exist, or existed in small numbers. The stories are all eerily similar: coastal waters in Spain have been documented to have as many as 10 jellyfish per square meter, along with an alarming sting rate of 70,000 people in 2006 alone; in Ireland a 10 mile wide swarm of jellyfish was responsible for killing 120,000 salmon; in Japan giant 6 foot jellyfish are being found in fishing nets annually in areas where they previously were only spotted every 40 years. Though the increased jellyfish presence has been noticed for several years, it has only been recently that climate change has been identified as a possible cause. For most scientists, the connection between an increase in jellyfish and an increase in water temperature is obvious. It has been well documented that jellyfish prefer waters that have warmer temperatures and higher saline concentrations and subsequently stay away from waters that are cooler and of lower saline levels. In previous years, this preference created a natural barrier that kept jellyfish out of coastal and cooler waters. As temperatures have increased however, the natural barrier has diminished and jellyfish are now comfortable navigating around many previously unexplored areas. Scientists note that coupled with the effects of warmer waters are an increase in population due to overfishing and lack of competition.
The increases in jellyfish worldwide have had many negative effects on the health of the ocean's ecosystems. When jellyfish find their way to new waters, they quickly take advantage of resources and grow immensely in population. In many cases, jellyfish populations take algae and other small food sources away from native fish populations in addition to eating the eggs of these fish. The result is usually drastically decreased native populations. Scientists predict that the spread of jellyfish will continue. Some scientists have even theorized that in the foreseeable future, jellyfish will replace penguins in the Antarctic. They believe this will be due to melting ice caps, which will reduce krill populations and penguin breeding grounds. As a result, the new smaller organisms will be highly conducive to the diet of jellyfish.
Jellyfish are clearly benefiting from climate change, but do so in a way that is detrimental to many other organisms, including humans. Jellyfish are responsible for the destruction of ecosystems throughout the world. Additionally, they are ruining fishing industries, tourist beaches and other staples of everyday life. In areas where there was once miniscule jellyfish presence, an invasion of millions has occurred. Scientists warn that unless greenhouse gas emissions and other global warming inducing factors are controlled, the jellyfish will continue to thrive and destroy.
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