Scientist's studies have revealed that human activities have caused the extinction of about 1% of all animal species each year, causing one in four species to disappear over the past 35 years. We are now seeing the effects of that more apparent than ever, as we watch the most rapid decline in major species occur today. "The Living Planet Index, which tracks nearly 4,000 populations of wildlife, shows an overall fall in population trends of 27% between 1970 and 2005." The main causes of wildlife extinction are attributed to: over-fishing, hunting, farming, pollution, climate change effects and urban sprawl.
This brings to light the most recent additions to the endangered species list, the polar bear and oceanic shark species. The polar bear is the first to be added on the endangered species list due mainly to global warming. Their habitat has been shrinking with the melting of the Artic sea ice. Scientists sadly predict that by 2050 polar bears will vanish from two of their four ecological regions. The threatened regions are home to more than two-thirds of the global population (see below map). Overall, the western Hudson Bay population has dropped by 22% since 1987. The global warming effect on polar bears have included bears actually drowning in open waters (due to ice masses shrinking) and cannibalism among hungry bears. Experts predict rapid population declines in the Artic, which is warming faster than anywhere else in the world and changing too rapidly for the bears to adapt and find other food sources. Not to be overlooked, of 21 species of sharks and rays, 16 are in danger of extinction primarily due to overfishing, which marks an overwhelming 76% of the population.
These recently added additions just raise more awareness that our planet is in fact in peril due to human interference with nature. The polar bear is a compelling symbol showing that what is happening to the them is also happening to the Artic because of the direct effects of global warming. And it is showing that it is happening more rapidly and more severely than anywhere in the world. This is signaling a red flag that we all need to take action on climate change. Reference: Los Angeles Times, Kenneth R. Weiss, March 15, 2008