Actually I Do think that we should do something to fight global warming, but not especially for the polar bears, I am too egoistic for that. The situation for the polar bear is just a symptom. The polar bear is a victim, just like we are. You and I thus. And as a victim the polar bear has my sympathy - now and loss of biodiversity is of course always bad (for everybody). Here are a few lines from the media in recent years:
Climate change is the number one threat to the 22,000 polar bears that remain in the world. (2002)
Polar bears are drowning because climate change is melting the Arctic ice shelf. (2005)
A U.S. Geological Survey study in 2007 concluded the projected decline in sea ice would mean the loss of two-thirds of the world's polar bear population by the mid-21st century.
Do the bears deserve special protection? (2008)
Should the endangered polar pear prompt action on climate change? (2009)
In fact it started with hunting. 40 years ago, widespread hunting had reduced polar bear populations in many parts of the Arctic. Thus, the polar bear range states, Canada, Denmark/Greenland, Norway, Russia and USA, entered into an agreement in 1973 to protect polar bears and their habitat. Well, hunting of polar bears has of course been important for the Inuits, and polar bears are essential to the livelihood for indigenous people in some areas, but hunting is no more what it has been. It must be based on sustainability. Polar bear hunters
see their culture melt away. Less sea ice means fewer bears, less income and questions about the future. In March 2009, Norway invited the five nations with polar bears in their territory to a meeting under the Polar Bear Agreement from 1973. The final report of this meeting is now available
In this document, the parties agreed that impacts of climate change and the continued and increasing loss and fragmentation of sea ice - the key habitat for both polar bears and their main prey species - constitutes the most important threat to polar bear conservation.
The parties noted with deep concern the escalating rates and extent of changes in the Arctic induced by climate change to date and that future changes are projected to be even larger. The parties agreed that long term conservation of polar bears depends upon successful mitigation of climate change.
In light of the growing concern over polar bear conservation in relation to climate change and a number of other emerging issues, such as oil- and gas activities, shipping and tourism, I am happy to say that the parties agreed to initiate a process that would lead to a coordinated approach to conservation and management strategies between the parties.
The most pronounced climate changes to the Arctic are likely to include increased temperatures and changes in precipitation patterns: both which will affect sea ice patterns and ultimately, polar bears. Polar bears will likely be shifted pole-ward if the sea ice retreats. According to new scenarios the polar ice cap will disappear almost entirely during summer in the next 100 years.
Because polar bears feed almost exclusively on ice-associated seals, changes in the sea ice that affect access to prey will have a negative effect on the bears. In particular, if more snow falls, polar bears are less successful at breaking into the birth lairs of ringed seals. If too little snow falls, ringed seal pups are born on the sea ice without a lair and this makes them very vulnerable to predation by polar bears and arctic fox. With less food, polar bears will fail to reproduce more often and give birth to smaller young cubs that have higher mortality rates.
Polar bears are totally reliant on the sea ice as their primary habitat. If climate change alters the period of ice cover, bears may be forced on shore for extended periods and forced to rely on stored fat. If these periods become excessively long, mortality will increase. If the ice changes in character such that there is more open water, young cubs which are unable to swim long distances may suffer greater mortality. Sea ice is also used for access to den areas and if ice patterns change, existing den areas may be unreachable. Another factor is that in some areas, warmer temperatures and higher winds may reduce ice thickness and increase ice drift. Because polar bears must walk against the moving ice (like walking the wrong way on an escalator) increased ice movements will increase energy use and reduce growth and reproduction.
Another problem is unusual warm spells during the period that females are on land in dens. If severe rain events occur during the den period, it is possible that snow banks slump and can kill mothers and their cubs.
Polar bears are a keystone species in ice-covered Arctic marine ecosystems and alterations to the distribution, density or abundance of this top predator will likely have impacts throughout the arctic ecosystem. There is little doubt that polar bears and other ice-inhabiting marine mammals in the Arctic, are being, or will be, negatively affected by the effects of climate change via changes to their habitats.