Geog350 Pauly

Title Changes in Polar Bear Habitat Due to Global Warming
Author Sidra Pauly American River College, Geography 350: Data Acquisition in GIS; Spring 2007 email: paulys@imail.losrios.edu
Abstract The purpose of the report comes from the increasing amount of articles about global warming and polar bears. The polar bear depends on the marine ecosystem of the Artic for survival, but the sea ice is rapidly melting. This is causing the polar bears to lose their habitat. Because of this loss, the bears have a need to search for food elsewhere. This in turn causes the increase numbers of polar bears being hunted by the Inuit hunters. Through extensive research on the Internet, scientific data was found and maps were produced of the Arctic sea where the polar bears live. However, the data conflict, and are in debate. There are several threats to the polar bear’s survival, and unless something is done to reverse the threats, their survival looks poor. Further research will be conducted in the summer of 2007, and decisions will be made by late 2007.
Introduction Recent articles about global warming have increased, with majority of the articles centered on the declining of arctic sea ice. Melting of the sea ice can cause many problems globally, and has been a concern of mine, especially when animal habitats are threatened. One specific problem that has been addressed recently is the survival of polar bears that depend on the arctic sea ice for their food and shelter. Observations of polar bears and their surroundings will produce statistical database and maps supporting these observations. Many of these observations are through the Inuit people in Nunavut, Canada and the Nunavut Wildlife Management Board. Environmental groups that are concern with global warming and its affects have also observed polar bears. The Inuit people however disagree with the other groups, and say that the populations are increasing. They say that the polar bears have been observed around settlements due to the need for food that they are unable to find in their normal habitats. Because of the increasing number of polar bears near settlements, they are threatened by being killed by humans who are afraid the bears will become aggressive towards them (Stirling and Parkinson). Reproduction is also threatened by the changing seasons with shorter winters that the polar bears depend on for their hibernation that is needed for producing their litter. They are also threaten by increasing numbers of other species that move closer towards the cubs’ dens because of warmer climates. Some polar bears have shown signs of cannibalism in search of food (Glick). These and other observations will be explored to prove what effect global warming has on the polar bears, and the need to reverse this effect in order for the polar bears to survive. Mother and Cubs
Background Polar bears (Ursus Maritimus) are classified as marine mammals for where they live and where their food source is located. The polar bears are the largest land carnivore, and have a distinctive massive body and long neck. They have translucent hair that reflects off the ice that gives it the color of cream to yellow. Their skin is black to absorb and preserve body heat. Their habitat is on the Arctic sea ice where they live most of the time. Nearly two-thirds of the world’s population of 20-25,0000 lives in Canada (WWF-Canada), and descriptions of polar bear populations have been obtained through many sources. These sources include indigenous people, wildlife and environmental groups, and by using satellite radio color data and other technology (Bethke, et al.). Through these observations, 19 populations have been identified in the world, of which 13 populations are in Canada. Of the Canada populations, there are 5 populations and possibly a 6th that are declining. This has put the polar bears on The World Conservation Union (IUCN) Red list of Threatened Species as ‘Vulnerable.’ The primary cause is due to global warming that is melting the sea ice. They are also subject to other causes, such as, pollution, over-hunting, and other cause sources (WWF-Canada). These causes will be addressed later in the report.
Global warming has caused the ice at the poles to melt at a tremendous rate, and the summers are getting closer. If the current trend continues with rising temperatures, the ice will most likely disappear. Because of the disappearing sea ice, polar bears are forced to make longer, riskier swims between iceberg islands. As the iceberg islands become more and more sparse, the polar bears can drown (Nicklen). Another problem that global warming is causing, is also declining of food source for the polar bears. Since the polar bears are strictly carnivores, they only scavenge for meat. With the decreasing number of food source, the polar bears have been turning towards cannibalism. They have also migrated south towards settlements. The natives of Nunavut has a quota that they are allowed for hunting of polar bears, but with the increasing number of polar bears south of their normal habitat, the number being hunted has also increased. map 1 - Canada in relation to neighboring countries. Most of the polar bear populations are in the northern area between Alaska of the United States and Greenland.	map 1
Methods When first looking for ideas for the report, I searched for information on GOOGLE, and the article database through Sacramento State University Library.The data and information from this research is used in my analysis. Some of the information and images are from articles (see References). Other statistical data and images on polar bears is from WWF-Canada, and Defenders of Wildlife. Maps were design with ArcGis 9.2 with data from Natural Resources Canada , and ESRI, with other locations for the Arctic Sea area from Geographica Atlas of the World (see References).
Results Majority of the area that will be addressed in this report is shown in map 2. These areas will be: Beaufort Sea Viscount Melville Sound Lancaster Sound McClintock Channel Gulf of Boothia Foxe Basin Hudson Bay Davis Strait Baffin Bay Norwegian Bay Kane Basin These areas along the Arctic Sea have been described as areas of stress for the polar bears.This map will also be used in reference to the tables and analysis	map 2
Table 1 shows Trends in Canadian Polar Bear Populations according to “IUCN 2006, Polar Bear Specialist Group Proceeding from 2005 meeting” (WWF-Canada). The Nunavut Government provided most of the data during the proceedings. The data shows recent population estimate compared to historic estimates, and the current trend with the estimate risk of decline within 10 years (WWF-Canada). Table 2 shows the recent population estimate along with the hunting season quotas along with the estimated increase of hunting quotas due to the migration change of the polar bears. This is some of the data that was provided at the Polar Bear Specialist Group Proceeding in 2005 (Stirling and Parkinson).
Tables Table 1 Table 2 Polar Bear Quotas
Analysis Polar Bear On Rocks After Swim The data from table 1 shows a decline in populations with an estimate of rising from the current trend. This data is inconsistent with the increase in hunting quotas in table 2. With the data of table 1 compared with observations from the articles, it is clear that the polar bears are declining populations. This data is also conformable to the increase in the sea ice melting due to global warming. However, there is a conflict with the increase in hunting by the Inuit hunters (table 2) and the Nunavut Wildlife Management Board. Nunavut wildlife board is facing the debate over reducing the hunting of polar bears. The Inuit hunters contradict the science data by saying that the populations are increasing, and the Nunavut wildlife board says the data shows the population dropping below 1,000 bears because of the shrinking ice that affects their health and survival. This is a conflict between the government going with the scientific information data presented to them and the traditional knowledge of the Inuits (CBC News). Originally, Nunavut raised the hunting quota levels in 2005. This raised the level in Baffin Bay alone from 64 to 105 polar bears (table 2). This was based on the Inuit’s knowledge; however, as the scientific data was presented to the board, there was a realization that the numbers were actually decreasing. The polar bears were just looking for food to survive. There is the problem that polar bears are very aggressive when it comes to searching for food. This proves to be a problem in making the decision towards the reduction or raising the quotas. There is a plan in the summer of 2007 for a full survey of the areas of conflict and take a closer look of the populations of polar bear and their distribution (CBC News). This will bring up to date the estimates of the populations where the latest estimates are 2004 (table 1). What is consistent is that the polar bear populations are changing, and this is concurrent to global warming. One cause related to global warming is the threat of the polar bear’s reproduction cycle. Polar bears normal reproductive rate is low, because they don’t mate until they are 5 years old, and don’t mate again until the cubs are 3 years old. The polar bears depend on the colder winters for their hibernation. Female polar bears need the hibernation in order to have their litter. During this time, the female that is carrying tend to eat less during hibernation then other polar bears. After birth, the mother will stay close to the den for food. With the sea ice melting, a threat to the area where the polar bears make their dens are increasing. If the polar bears do manage to have a litter, there is a threat that there will be no food after birth (Glick). Global warming is causing the food sources to diminish. For example, the Lancaster Sound is “one of the most productive marine habitats in the world” (Nicklen). There are minute life forms that feed off of the ice, and other animals – polar bears, whales, birds, and seals – depend on these life forms for their survival. As for the polar bears, they depend on the seals as one of there major food source, and if the seals diminish due to the minute life forms no longer feeding on ice because the ice is melting, the polar bears will either starve or go elsewhere for food (Nicklen). The polar bears also turn to cannibalism, which isn’t uncommon among bear species, but it is increasing in the Arctic due to the decreasing food supplies for the polar bears (WWF-Canada). Global warming isn’t the only threat to polar bears. There are many other threats. Some of the threats are related to global warming, but there are some related to economic gains. The full list according to WWF-Canada is: Main Threats: Global warming (especially the melting of sea ice, and changes to marine food supply and availability); Contamination of food supply by toxic chemicals such as persistent organochlorine pollutants (DDT, dieldrin, dioxins, etc.) and heavy metals such as mercury; Marine oil pollution and disturbance associated with increased industrial and shipping activities in arctic waters; Disturbance to key habitats from industrial explorations and developments (e.g., denning concentrations in oil-gas rich areas); and Over-hunting. Less Significant Factors: Intraspecific predation (i.e., cannibalism, often seen in bear species); Increased conflicts with humans along Arctic coastlines (human safety issues, often requiring removal of polar bears); Scientific research; and Tourism.
Conclusions If the current trend continues, the polar bears will become extinct. At this time, they are on the “World Conservations Union (IUCN) ‘Red List’ of Threatened Species as ‘Vulnerable’” (WWF-Canada). The reversal of global warming is a long process, but if the world cooperates together, it can be slowed, and eventually the reversal can begin. However, there are to many conflicts of what is needed. There is a need for more observations before a decision will be made on the outcome of the polar bear. The Canadian government, and the U.S. Endangered Species Act (ESA) will make many of the decisions about the polar bears by the end of 2007. Since global warming is not the only factor, there will be a need to change these factors, also. Otherwise, the polar bear is destined to be extinct.
References Bethke, Ray, Mitchell Taylor, Steve Amstrup, and Francois Messier, 1996. “Population Delineation of Polar Bears Using Satellite Collar Data.” Ecological Applications, 6(1):311-317. Geographica: The complete illustratioed Atlas of the World. Australia: Mynah, 2006. 382, 410-411. Glick, Daniel, 2007. “On Thin Ice.” National Wildlife Magazine, 45(1). Nicklen, Paul, 2007. “Vanishing Sea Ice.” National Geographic, 211(6):40-55. Stirling, Ian, and Claire L. Parkinson, 2006. “Possible effects of climate warming on selected populations of polar bears (Ursus maritimus) in the Canadian Arctic.” Arctic 59(3):261(16) Time, 2006. “Special Report: Global Warming.” Time, 167(14):28-37. Back