Global Warming In West Hudson Bay

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Life on the melting Artic is hard and unforgiving for all animals that rely on the annual ice change to obtain their food source or as a habitat. Increased ice melting rate and degrading habitat from global warming has altered polar bear life expectancy in the West Hudson Bay. Counterclockwise marine currents in the Hudson Bay “behaves essentially as a closed ocean body in that the duration of the ice thickness and ice cover is essentially controlled by air temperature and variations” (Gagnon and Gough, 372). Simple changes within the atmosphere can have a detrimental effect on the duration of ice thickness and covers and will affect the polar bear survival success rate. Thinner ice will be melted during the summer and lower the available hunting …show more content…

Annual ice buildup in additional to a healthy seal population is vital for polar bears to mate and maintain a healthy population within the Hudson Bay. The rise in global temperature in the past decade has led to a decline of lone (likely pregnant) adult female polar bears in the Western Hudson Bay from 1980 to 2004 (see figures above) (Stirling and Parkinson, 274). The average female between 6- 18 years old has “an average litter size of 1.7, a sex ratio at birth of 1:1, and an average reproductive interval of 3.1 years” shows the average female can give birth up to 4 bears in their life time (DeMaster and Stirling, 3). The decrease in average monthly ice extends correlates with the mean body mass of lone female polar bears in the West Hudson Bay region. The earlier breaking-up of arctic ice likely shortened polar bear’s seal hunting time in Hudson Bay because less time to hunt directly affects the size and weight of female bears. Cubs are also likely to receive less nutrition from malnourished mothers and decrease survival rate. The hunting period before summer are responsible for nearly 70% or more of the energy bears needed to survive throughout the year. The early break up is causing adult polar bears, especially, females have less body mass. Data of sea ice breakup has shown that the “average date of break-up” is …show more content…

The shift in seasonal ice pack in the West Hudson Bay has changed polar bear behavior, reduced prey availability, lowered birth rate, and a positive effect on polar bear and human conflict. Polar bears require seals and other high fat animals for their survival in the arctic region. The decrease in ice packs also reduces prey abundance and increased bear mortality. Seasonal break up rate has increased and reduced seal availability within the Arctic region. The Lack of food has decreased female polar bear sexual reproductively as well as body weight. Finally, polar bears are encroaching onto human territory. Human safety is being threatened as bears go on land, instead of their usual habitat, to forage for food. Humans are forced to kill bears to protect themselves. Lastly, polar bear’s future is grim. Studies have predicted bears will lose a third of their habitat by 2100. Soon these polar bears will become extinct in the 6th global mass extinction. Humans must reevaluate their population output and seek ways to preserve the polar bears for future generations to

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