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Arctic Fox
Throughout the world, the ability for animals to thrive is based on a series of factors that make up their ecosystem; changes in the availability of prey, vegetation and weather all have the ability to affect an ecosystem. In many of the world's ecosystems there is a great deal of flexibility available and many animals are able to adapt to changing settings. In other, more rigid structures, changes in ecosystems are more difficult and it is through this fact that the troubles of the arctic fox are introduced. Living in the very delicate arctic tundra, the arctic fox is suffering greatly from climate changes brought about by global warming.
It was previously thought by scientists that global warming and the melting ice sheets that followed would force arctic predators to migrate, but recent studies show that they are causing them to disappear; this is especially true for the arctic fox. In the various areas that it inhabits, which include Greenland, Russia, Canada, Alaska and Scandinavia, scientists are discovering that warming climate is affecting their livelihood. The most dramatic example of this can be seen in Scandinavia, where the arctic fox was once one of the most prevalent predators in the Scandinavian arctic tundra, but now numbers have dwindled to about one hundred. This dramatic decline in population has placed the arctic fox on the endangered species list in this area. The effect that climate change has had on this decrease has been attributed to a variety of factors. A main effect of global warming on the arctic fox is that changing temperatures result in reduced presence of prey in the delicate tundra ecosystem. The absence of necessary levels of prey, mainly being lemming, greatly affects the arctic fox's reproduction rates; it has been discovered on years with low lemming levels, many arctic foxes do not reproduce at all. Another newly discovered factor is a growing awareness of the arctic fox's dependence on ice scavenging for survival. In a study done on a series of arctic foxes in Northern Alaska, it was discovered that out of 17 observed foxes, only the three that spent their long winter months scavenging on ice survived. Scientists feel that this increased survival rate is due to the fact that there is less competition on ice than on land and that melting of ice shelves will lead to reduced arctic fox survival rates in the future.
Scientists fear that as the climate continues to rise, the arctic fox may vanish from certain regions, if not all together. Support for this theory comes from a study of DNA from arctic fox remains from more than 20,000 years ago. By looking at the remains of arctic foxes, who once roamed the lower areas of Europe during the last ice age, it was seen that there was no genetic connection between these remains and the present day Scandinavian foxes. This shows that the foxes did not retreat to the north, but instead were eliminated by the rapid ecosystem changes associated with climate change.
While many still try and argue against the effects of global warming, it is an issue that is hard to debate when looking at the case of the arctic fox. Though once a dominant predator, the presence of the arctic fox has slipped to staggering low numbers in many areas. Climate change affects the habitat, resources and reproduction abilities of the arctic fox and unless changes are made, the arctic fox could be lost forever.
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