Population Growth |
Historical data of the population size of polar bears. |
Polar Bears Statistics
(Gayathri, 2011)
Graph description The graph demonstrates an increase of polar bears, this is because the line of best fit includes the year 1970 where there was an overhunting of polar bears causing the polar bear number to drop drastically. These numbers are also estimations thus they are not accurate measurements. If the year 1980 is compared to 2014 it is seen that the polar bear has decreased almost be 10000 polar bears. This graph also lacks regular intervals of the polar bear population, but this is due to lack of sampling done by organizations. There is not enough sampling data done to be able to graph the polar bear population and show an accurate representation.
Based on the line of best fit on this graph, the polar bear population is predicted to increase in the next 5 years to a population of 26023 polar bears. Polar Bears and ice-This video explains the effects of global warming on the polar bear and how it's causing a reduction of ice, therefore causing more obstacles for the polar bear to overcome.
- The main issue affecting polar bears is the melting of ice reducing their habitat and increasing intraspecific competition (National Wildlife Federation, 2011). |
Limiting factors: The increasingly warming climate is damaging the population due to polar bears being specific to a very cold environment. Polar bears cannot be threatened by other animals since they are at the top of their food chain. Polar bears are directly related to how we, the humans, are treating the earth. Global warming is affecting the amount of frozen ice which directly affects the bears since they fish for seals on that ice. Polar bears also live on that ice, thus when the amount of ice decreases the number of drownings increases. By decreasing the amount of ice, the habitat of the polar bear is reduced increasing competition for food between other members of that species (intraspecific). Due to this intraspecific competition, cannibalism occurs which furthermore decreases the polar bear population. Scientists can confirm through deep core experiments of ice which show CO2 concentration that polar bears are used to very snowy and cold environments (National Wildlife Federation, 2010).
Persistent organic pollutants (POPs) which are poisonous chemicals and substances also affect the Arctic even though most of them are banned. Through recent tests, these chemicals show up in the Arctic habitats (Tenenbaum, 2004). These chemicals can affect the polar bear's diet and body through poisoning which results in illness or death. Other limiting factors include human hunting either illegal or legal. Legal hunting is done by Native people for traditional purposes whereas illegal is just for the black market. The problem of hunting was especially prominent in the 70's due to overhunting that caused the polar bear population to decrease to 5000-10000 (National Wildlife Federation, 2010). Another contributing factor to the decrease of polar bears is the expanding industrial developments such as oil spills. This is a problem in our current time due to our rapidly expanding and demanding industrial developments. Oil spills and industrial developments cause disturbances with noise, destruction of habitats, poisoning, and reduced insulation in the polar bear's fur (Russian Federation, 2013). |