Essay On Polar Bear

Introduction:

In this report I will be using the Polar Bear (Ursus maritimus) as my chosen species. The Polar bear is the largest land living apex carnivore in the world where males can reach a mass of over 450 Kg and females between 150 Kg to 350 Kg. Instantly recognizable by their white fur coat which is technically transparent where it is the reflection of the snow that gives the Polar bear its beautiful white coat. As a Polar bear’s skin is black allowing for some heat from sunlight to aid in respiration. They are located all around the Arctic Circle. From Canada to Greenland to Russia, their range is vast due to the travelling they must endure to reach plentiful sources of food which is primarily seals however they have been known to hunt walrus and beluga whales.

The role the Polar bear plays in its habitat is a huge one by being a keystone species where by the rest of the subsequent food chain rely on the polar bear to survive especially the lesser carnivores such as artic foxes and wolverines. They also keep down seal populations, especially Arctic permeant species such as the Ringed seal. By hunting on sea ice the polar hunts for the cubs of the seals by breaking into warrens located under the ice, if lucky the polar may catch the adult seal which would be a larger meal. If the not all the meat is eaten then scavengers then feed on the rest, thus giving

In the artic plants are hard to come by especially the further to go onto the arctic cycle, how polar bears can suffer with artic mites which can lead to infections which can lead to the Polar bears eventual death. This is a biotic factor by means of a parasite killing its host this lessens the population but this a minority of cases. The main biotic factor that influences polar bear numbers is other polar bears killing each other over food, mates and