Final paper Assignment - Research Proposal Example

They are distributed throughout the ice-covered sea of the circumpolar Arctic. The sea ice is their primary habitat. They depend on it for successful hunting of seals, which enable them to accumulate enough energy to sustain them during periods when seals are not available (Stirling & Derocher, 2012). There have been changes in the distribution, structure and pattern of break-up and freeze-up of the sea ice in the circumpolar Arctic. These changes have been as a result of the increasing climatic changes and global warming (Stirling & Derocher, 2012).

Ice in the Arctic was recorded lowest in 2002, and it has been determined that ice season is decreasing up to eight days in a year (Welch, 2012). Changes in the pattern of sea ice such as increased break up of ice lead to reduced access to seals by the polar bear and results in longer fasting periods that lowers the body condition. Consequentially fewer and smaller cubs with lower survival rates are produced. The survival rate of bears of other ages also declines. The above conditions lead to declined subpopulation and eventually might result in extinction of the polar bears (Derocher et al., 2013). Due to the threat of extinction caused by global warming, polar bears were listed as endangered species by the FWS in 2008 (Welch, 2012).

The effects of climatic changes are very evident in the southerly subpopulations particularly in Hudson Bay (Derocher et al., 2013). It is expected that with the continued climate change, the polar bears will migrate to the northerly areas, which include Canadian Arctic Island and northern Greenland. These areas, which are currently facing thick multiyear ice and little light penetration to support productivity, might be replaced by annual ice that supports high level of productivity compared to the previous states due to global warming and create a favorable habitat for the polar bears (O’Neill et al, 2008).

Climate Changes and global warming