The numbers of Polar Bears have been decreasing and it is estimated that the arctic ice will be totally gone in 100 years , making it inevitable that the Polar Bear will die. Why are they becoming extinct? Global warming is the main cause of the Polar Bears decrease in population. The Polar bear lives in the North. The reply on the cold weather for their food but because of Global warming the earth is warming and their numbers is decreasing. The earth’s temperature has increased from 1920 to 2005 [fig 1] which has had a devastating effect on our polar ice caps, shrinking the size of the poles.
As the temperature increases the Polar ice caps melt faster therefore the Polar Bears population decreases quicker. Also, as the temperature of the earth increases the numbers of fish in the poles decrease as they are not suited to the rising temperatures. This is doing further damage to the numbers of Polar Bears as this means less food for them to eat. Also, Polar Bears are not aquatic so they depend on catching, their main food, and seals on the ice. What is melting ice doing?
Global warming is devastating the amount of sea ice in the arctic. The sea ice in the Arctic reached a record low in 2006, but that was shattered by the record of 2007. The size of Texas and California combined was reported to have melted in the arctic.  In the 1970’s Polar Bears were off the ice for approx 120 days, in 2010 that number rose by 40 days to 160 days. This means the Polar bear has on average 10 less days of catching food a year now compared to 1970. This causes Polar bear numbers to decrease because they can starve.
Also, the numbers of polar bear cubs is decreasing because a female polar bear must have a good fat supply to have cubs and if the amount of food is decreasing this in turn leads to the decrease in polar bear cubs as the females become pregnant.  Why are they important?  They are at the top of the eco system. If the Polar Bear becomes extinct it can lead to extinction of other animals. The Polar Bear feed’s on seal, dear and fish.  If the Polar Bear becomes extinct the numbers of these animals will dramatically increase as there main predator is no longer a threat.
This would then lead to the downfall in the numbers of animals which the seal, deer and fish feed on leading to a big change in the food chain and the exaction of more animals How do we know their numbers are falling? Aerial surveys of Polar Bears help give a quick and cheaper way of counting the population of Polar Bears than traditional methods. It also gives a more accurate observation as it can be done quickly reducing the risk of counting bears twice.
Also, some Polar Bears have tracking devices to determine their location, breading and hunting patterns and to measure distance travelled.  Solutions Reducing global warming would go a long way to stop the Polar Ice caps from melting therefore stop the reduction in numbers of Polar Bears . This means burning less fossil fuels; oil, coal and gas therefore producing less carbon dioxide. We can use solar power, wind power, hydroelectric power and other alternative cleaner sources of power instead of fossil fuels which will not contribute to global warming.
We can also stop deforestation. Trees convert carbon dioxide into glucose during photosynthesis but when a tree is cut down and burnt the carbon dioxide is released increasing the carbon dioxide concentration in the atmosphere . This means more carbon dioxide is released and less is stored. Also, to stop the extinction of Polar Bears we could bread them to ensure stable numbers. The implication of this are that Polar Bears are wild animals so they shouldn’t be kept in small places and it would cost a lot to replicate their natural environment. This would make it very hard to breed them.
Also, they are such large strong animals and they live in such harsh conditions for humans it would be hard to catch the animals to breed them as it would be very hard to catch them and transport them. Also, they are such large animals it takes years afford them to reproduce making breading them a long and costly process. However, it is possible to transport the animals, they would have to be kept in steel cages, drugged during transportation and flown to the area they would breed and be monitored in. This could increase the numbers and also give more information into other causes of why they are endangered.