This essay first appeared in STAY COOL - A Polar Bear's Guide to Life by Jonathan Chester and Patrick Regan
The loss of an iconic species such as the polar bear is but a symbol of much larger and hugely significant changes that will occur in many ecosystems throughout the world if the climate continues to warm. For polar bears habitat loss is the most critical single concern… If the population of the planet is truly concerned about the fate of polar bears we need to collectively reduce greenhouse gas production significantly and quickly.
Dr Ian Stirling Senior research scientist for the Canadian Wildlife Service.
Dr Andrew E. Derocher, Professor of Biological Sciences University of Alberta, Canada
Polar bears are truly magnificent creatures completely at home in the frigid Arctic. They are the largest species of bear, the largest land predator and rank at the very top of the Arctic food chain. When standing erect mature males can reach up to nearly 9 feet, (3 meters), and are roughly twice the mass of females. Over the past 100,000 years these bears have evolved and adapted to thriving on and with the circumpolar Arctic sea ice. They are totally dependent on it for they major portion of their diet, for movement, resting and reproduction.
Today some 20,00 to 25,000 wild polar bears are estimated to live across the vast Arctic region in 19 discrete populations. In the past the polar bear habitat was relatively pristine, consequently the threat to polar bears came mostly from hunting and human development that was encroaching on the fringes their range. There was a sustainable balance in the traditional hunting practices of the Inuit that was upset with the introduction of rifles, hunting from aircraft and icebreakers. These changes saw polar bear numbers decline dramatically beginning in the 1930s. This accelerated in the 1960s with the advent of increased aerial hunting. In 1973 the 5 countries that border the Arctic the USA, Canada, Greenland/Denmark, Norway and the then Soviet Union made an historic agreement called The Conservation of Polar Bears that committed the parties to restrict hunting and protecting the bears habitat, denning areas and migration routes. As a result of these measures by the 1980s polar bear populations crept back to today’s levels.
While polar bears are not yet considered an endangered species, their future is far from certain. in 2006 they were added to the International Union of Conservation IUCN Red List and classified as Vulnerable on the basis of the projected affect global warming will have on the Arctic sea ice as determined by the IUCN Polar Bear Specialist group. This body of biologists and climate scientists forecast an overall decline in the total polar bear population of more that 30% in the next 30 to 50 years. The figures are constantly being revised upwards as new models are developed and studies are reported. There is some suggestion that the entire species will disappear by the turn of the century.
Today, in addition to the enormous effects of climate change, polar bears face unprecedented threats to their well-being in three main areas: increase pollution, oil and gas development and transport, hunting.
Being the top predator in the Arctic ecosystem pollutants become concentrated in the fat of polar bears with severely compromising reproduction and other biochemical pathways. They are building up to dangerously high levels as a result of the bears eating seals that are in turn contaminated by organic pollutants and toxic chemicals such as heavy metals, PCBs, radioactive elements and pesticides that the seal accumulate get from eating filter feeders lower down the food chain. The pollutants are very persistent and may well enter the environment far away from the Arctic, but be carried there by winds and ocean currents driving northward from more populated areas. Pollution affecting bears can also come from more local sources.
While development activities and industrial facilities associated with oil and gas exploration and extraction have been show to be tolerated relatively well by bear populations, oil spills pose a serious potential threat. Bears and their prey are at risk of direct exposure to oil in the event of a major spill.
Road’s and pipelines that are developed in support of oil and gas exploration and the opening up of shipping lanes, plus the inevitable encroachment of human settlement, military activities and growing tourist industry will result in more face-to-face confrontation between polar bears and humans. While polar bears are curious and generally fearless and they can do major damage to property, they do not typically attack humans unless a female bear is protecting her cubs or the bears are starving.
Some places like Churchill in Manitoba, Canada have been able to capitalize on their proximity to areas where large numbers of bears gather in the fall waiting for the ice to form on Hudson Bay. Since the 1970s an increasing flow of adventurous tourists are drawn to the self proclaimed “Polar Bear Capital of the World” where they are able to see polar bears in large numbers from the relative comfort, safety and security of so the called tundra buggies. These oversized rugged buses riding on giant tires ensure that humans are out of reach of the very hungry polar bears with minimal impact on the fragile tundra ecosystem. The town of Churchill itself has to contend with the ever-present threat of bears wandering into the built-up areas and rangers patrols the streets during the fall polar bear season. Wherever possible bears that stray into the city limits are trapped and contained in the “polar bear jail” until sufficient ice is formed on Hudson Bay when they can be safe relocated and are unlikely to return. In certain circumstances especially when there is a female with cubs, or the jail is full, bears will be relocated by helicopter some distance north.
Occasionally bears are shot in self-defense but in some parts of the Arctic particularly in traditional communities bears are still harvested as part of a subsistence traditional lifestyle but in the Russian arctic there is little to no monitoring of hunting and poaching is prevalent. While much of the traditional hunting of polar bears by local communities was sustainable, it is now believed that more recent tag limits have been based on erroneous population estimates and that the indigenous quotas do not take into consideration the effects of climate change on population reduction.
Global warming is affecting all aspects of life and the ecology of the Arctic. Studies have shown that air temperatures have increased sharply over much of the Arctic region in recent decades. Records show there has been a 5 degree C ? degree F rise in the last 100 years. Overall sea ice cover in summer has declined by 15% to 20% over the past 30 years. 2007 was the least amount of summer ice on record and subsequent summers have only shown a modest improvement. Looking ahead the US geological survey models suggest that the preferred habitat, the sea ice cover on and near the continental shelf will decline by almost 70%during spring and summer towards the middle of the century.
With sea ice has been breaking up earlier in the spring and freezing later in the fall this lengthens the time the bears must fast. Most experts now believe that the decline in Arctic sea ice could result in the loss of two thirds of the polar bear population within the next 50 years. There is growing evidence that global warming is affecting polar bear populations through increased death rates from drowning, cannibalism and fasting. Of the 19 recognized populations studies have shown that 8 are declining in numbers, I is increasing 4 are stable and there is not enough data about the remaining 6 to be able to make any assessment either way.
As a result of this alarming situation various governments around the world and especially those boarding the Arctic have been taking action individually and in co-operating, notably the USA, Canada, Greenland, Norway and Russia. Some positive steps have been taken but there is much more to be done. There is increasing pressure to ban the trade in polar bear artifacts, claws, hides and skulls. The mechanism for this is the up listing of polar bears from the “regulatory” Appendix II to the “prohibited” Appendix 1 in the Convention on International Trade in Endangered Species and of Wild Fauna and Flora (C.I.T.E.S.)
Under pressure from the pubic and non-profit groups like The Center for Biological Diversity, the US government has also been taking steps to protect polar bears and manage new realities of the warming world. In May 2008 the US Department of the Interior listed polar bears as threatened under him under the Endangered Species Act because of decreasing sea ice. In October 2009 the Department of Interior also announced it planned to designate 500,000 km² (128 million acres) of Alaska’s north coast as “critical habitat” This encompasses the entire range of several Alaskan bear populations numbering 2500 individuals and we protect the bears ice habitat as well as barrier islands. While this measure does not address the underlying problem of habitat loss due to global warming, it’s does represent a positive step recognizing the need to manage areas in the Arctic where bears currently still exist. More work needs to be done to increase the international legal protections for polar bears as their ranges cross many national boarders.
These government steps all need popular support to be created and enacted. There are a number of other organizations that are focused on educating people about the plight of polar bears and offer information and resources as a way of providing legislators and policymakers with the necessary scientific information to make important decisions. Polar Bears international is solely focused on education and funding scientific research but other global NGOs such as the World Wildlife Fund and Defenders of Wildlife and the David Suzuki Foundation also have extensive campaigns focused on the Arctic and polar bears We all need to take greater responsibility for our contribution to the problem of increased greenhouse gases and try and minimize our carbon footprint. Small personal actions modifying how daily routines to be more energy efficient from the way we eat, cool and heat our houses, transport ourselves, and consume all manner of resources. When added together across millions of people can make a significant contribution. Ensuring that our politicians and policymakers are also making informed decisions on behalf of our country is also equally important, as this is a global problem. It requires leadership, the burden of which falls squarely on developed nations given that have the resources, technology and are, per head of population, some of the worst offenders in terms of output of greenhouse gases in the first place.
So will polar bears sink into oblivion in decades to come only to be found in Zoos their or will they survive to hunt and thrive in renewed icy arctic. We are all part of the problem but we can also be part of the solution.
Polar Bears International
http://www.polarbearsinternational.org/
World Wildlife Fund
http://www.worldwildlife.org/species/finder/polarbear/polarbear.html
Defenders of Wildlife
Center for Biological Diversity
http://www.biologicaldiversity.org/species/mammals/polar_bear/index.html#
The International Union for the Conservation of Nature IUCN/SSC Species Survival Commission Polar Bear Specialist Group
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