Impacts of Climate Change to Polar Bears

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Background

Polar  is one of the largest types of bear and the largest land predator. The bear differs in size; there is a difference between a female and the male polar bear, whereby the males can weigh around 350-900 kilograms. The male weighs two times more than the females that weigh about 150-300 kilograms. Bear body weight vary with season specifically the female bear, which is regularly double in mass between late summer and early spring. Matched to other types, the polar bear has narrow and long head and claws that are more powerful (Steven., et al 12).

The sharp and long predatory teeth help the polar bear to acclimate to the Arctic temperature that is changing and to its carnivorous lifestyle. The polar bear is the youngest species of the bear family and is closely related to the brown bear as well as the grizzly bear. The arctic climate considered favorable for the bears since they depend on it for their survival, hence the destruction of the climate via global warming it a threat to these animals. This research paper covers the impacts of climate change on the polar bear.

Ecology

The polar bear is one of the most formidable predators, and it is ranked at the top of the Arctic food chain. The most common prey for the polar bear as well as the standard and readily available food for the polar bear is the bearded and ringed seals. However, the polar bear is considered as the most opportunistic predator in the Arctic when it comes to food; hence it can eat other available seals when offered the chance or opportunity (Dybas 1018). Greenland seals, hooded seals, walruses, beluga whales, as well as the narwhals among other types of big fish, may as well be included in the polar bear diet out on the sea ice; the main hunting ground.

On land, the bears can catch reindeer, eggs of birds, geese, and the carcasses of whales washed offshore. Contrary, bears cannot eat grass or seaweed that they attain by diving. It can deduce that polar bears are reliant on sea ice to get their food hence the sea ice level should not be compromised and if it is compromised then the lives of the bears will be threatened.

In the wild, polar bears have a life span of only 25-35 years. Both female and male polar bears mature at the age of five to eight years. Female bears delivery the first cubs when they reach maturity, but this is dependent on food availability, while the male start mating when they are eight to twelve years old. The mating season is also determined by various factors; however, it is mostly between April and May but there is always a delayed implantation meaning that the fetus development does not start until September or October.

During late autumn, female polar bears go into hiding for almost four months after which the cubs are born mostly at the beginning of January depending on the mother’s condition and age. The born cubs are born with a small weight, weighing only half a kilo, but they have a fast growth rate due to high fat content milk from the mothers. The cubs stay with their mothers until they attain two-three years. The cub infant mortality rate is about 75 percent, the means that around and eighth of the cubs reach the age of three. Thus, survival rates of the cubs depend on the habitat their mother is in as well as the diet taken by the mother polar bear.

Distribution and population status

The polar bears are considered circumpolar species found in the Arctic whereby they have access to sea ice all through the year. Polar bear populations are dominant in Alaska, Canada, Russia, Greenland, the Norwegian Artic and other regions surrounding the North Pole. The world’s population of the polar bear comprises of only 20,000 to 30,000 individual bears spread in about 20 sub-populations. The means that the number of the polar bear is not large enough as compared to other animals in the world hence easy of being eradicated because of climatic changes if not maintained. However, polar bears move across vast distance, so there is no genetic difference between polar bear species. The distribution of the polar bear in their habitat is far from being uniform since it is dependent on various factors but mostly the availability of prey. In the polar icecap, there is limited access to food hence the density of the polar bear is considerably lower hence lower reproduction of the polar bears in this region. Based on the above fact, it can be deduced that number of the polar bear in a given areas is heavily dependent on the availability of food when other factors are kept constant. In addition, the movement of polar bears from the icecap regions is due to reduced availability of food due to reduced sea ice caused by climate change (global warming).

On Svalbard, polar bears only live in regions with sea ice; hence most of them are found at the eastern coast. The most significant hibernation zones are the island of Edgeøya and Hopen since the sea ice is withdrawing due to global warming, the bears have clogged hibernating on Svenskøya. This is a sign that these vital hibernation zones are under threat due to global warming (Walsh 6). It can be concluded that the sea ice is greatly affected by climate change are very soon the polar will migrate to other regions that have cold climate and since they are predators they have to adapt to other types of food like other carnivorous such as lions and leopards or go to extinction.

Because of these changes in climate, the polar bears were proclaimed vulnerable on the Worlds Conservation Union and included in the Red List. Since the pola.............


Type: Essay || Words: 1943 Rating || Excellent

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