Descriptive essay

Hi, I must write descriptive essay and I'm not sure with this one. Can it somebody correct??
Polar bear live in the Artic Circle, which include Artic Ocean and land masses. They are very good swimmers and hunters. The scientist estimate that two-thirds of the polar beer population can disappear by 2050.
Polar bears are stark white and have thick coat of warm fur. They have got black skin under the fur. Average lifetime in the wild is twenty-five to thirty years.Adult male are about 100 kg and more heavier than adult female.
Bears live alone because they spend most of their life at sea. They hunt their feed from the edge of sea ice. Females period is about eight months lenght and produce between one and three cubs in den. Cubs are very small when born, their weight is about 0,5 kg and lenght 30 cms. Cubs stay with their mother until they are 2,5 years old.
However climate changes rack that sea ices are getting thinner and they can not hold weight of polar bears. So they died to enervation. Another problem is hunting polar bears for their fur.
Most ZOOs in the world produce polar bears. In 2008 United States placed polar bear as a threatened species under the Endangered Species Act.

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