Polar Bears Versus Extinction - Humanitys Effort to Save a Species
The Arctic is a vast, ice-covered sea surrounded by treeless, frozen tundra teeming with wildlife - including organisms living in the ice, fish and marine mammals, birds, land animals, and human societies. And, for thousands of years before the presence of humans, the polar bear reigned as the highest predator in the food chain of the frozen Arctic.
Threats of Hunting and Melting Sea Ice
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Today, there is an effort underway to place the polar bear on the Endangered Species list. In July 2006, the House of the United States voted on and approved a U.S.-Russia treaty to protect polar bears from over hunting by native populations and creates a commission to study the loss of Arctic sea ice. Due to melting sea ice - polar bears sometimes drown swimming the increased distance between ice islands as they search for food.
This treaty was prompted by dwindling numbers of polar bears. The World Conservation Union (WCU) of Switzerland estimates the number of Arctic polar bears has decreased from 25,000 to 20,000. It is estimated that 15,000 polar bears live in Greenland and Norway - while 5,000 live in Alaska, Russia and Canada. Documentation of a defrosting Arctic came in 2004 in the Arctic Climate Impact Assessment (ACIA). The ACIA was an unprecedented four-year study by an international team of 300 scientists.
Support for polar bears being listed as endangered made headlines when three groups took legal action in 2005. The Natural Resources Defense Council (NRDC), the Center for Biological Diversity, and Greenpeace, filed suit in U.S. courts to prompt placement of polar bears on the Endangered Species list.
Eating High on the Food Chain
Bioassays of the Arctic's wildlife and people have verified the presence of high levels of toxins. Today, the Arctic's indigenous people and predator animals are considered some of the most chemically contaminated life forms on our planet.
Due to location, polar bears and indigenous people eat animals high on the food chain. By doing so - they ingest chemicals that are concentrated in the fat of animals such as seals, whales, walruses, and other animals.
Beluga whales, for instance, serve as a food source for polar bears and indigenous people of the Arctic. While Arctic natives have their long established methods and rituals for hunting whales, polar bears have evolved their own unique methods for capturing beluga whales.
Arctic beluga whales have food in abundance. However, when the Arctic freezes - the whales need to surface every ten to twenty minutes to breathe. Over millions of years, whale pods have developed ways for keeping breathing holes open in the ice. By swimming in a continuous vertical circle to the surface - the whales prevent ice from forming in their breathing hole. When the hole is large - many whales may surface for air at the same time. However, as thickening ice and extreme subzero temperatures reduce the size of the hole - the whales organize themselves to take turns. Eventually, as the long Arctic winter sets in, and the whales become stressed and tired - an opportunity for the polar bear presents itself.
Polar bears wait along the edge of the air hole; when a whale surfaces, the bears leap in and slash the whale with their long sharp claws. Eventually, the weakest and most injured of the whales will succumb and die in the air hole, giving the polar bears a substantial feast.
Even though beluga whale blubber is a high-energy source - it also contains about 80 parts per million (ppm) of the PCB chemical. By contrast - most people have less than 1 ppm. In 1987, high levels of PCBs were found in the milk of nursing Inuit mothers. This discovery caused international concern and raised awareness of the migration of toxic chemicals by ocean currents, sea life, and atmospheric deposition.
The International Threat of Chemicals
Since the Arctic is a region of international interest and overlapping ecosystems, a group known as the Arctic Council was formed. The Arctic Council is composed of members from Iceland; Canada; Denmark; Russia; Sweden; the United States, and Norway.
Studies released in 2004 by the Arctic Council report that "legacy contaminants" such as PCBs and DDT are the dominant chemicals found in Arctic wildlife. DDT and PCB's are considered some of the world's most toxic contaminants. Other Persistent Organic Pollutants (POPs) found in Arctic wildlife and indigenous people include dioxin, PBDEs (flame retardants), and PFOS (stain repellent chemicals).
Flame retardants are found in consumer products such as fabrics, computers, and certain building materials, while stain repellents are found in consumer products such as fabrics used for clothing, furniture and automobile seats.
A paragraph in one study states:
"Environmental contaminants such as persistent organ pollutants (POP) pose an additional area of increased concern for polar bears. Recent documentation of baseline contaminant levels in the circumpolar environment and in key species has dramatically expanded the knowledge of regional presence and levels of these pollutants over the past 10 years. Polar bears, as an apical predator, tend to amplify the bioaccumulation of organochlorine compounds, and are a perfect candidate for studies in evaluating trends. We now know that polar bears inhabiting certain areas of the Arctic exhibit elevated levels of organochlorines, particularly PCB's (poly chlorinated biphenyls) while populations inhabiting other areas have lower levels. Laboratory experiments involving elevated levels of organochlorines have been associated with a range of effects including neurological, reproductive, and immunological changes. Studies continue to evaluate the effect of persistent organic pollutan
The Arctic is a vast, ice-covered sea surrounded by treeless, frozen tundra teeming with wildlife - including organisms living in the ice, fish and marine mammals, birds, land animals, and human societies. And, for thousands of years before the presence of humans, the polar bear reigned as the highest predator in the food chain of the frozen Arctic.
Threats of Hunting and Melting Sea Ice
Today, there is an effort underway to place the polar bear on the Endangered Species list. In July 2006, the House of the United States voted on and approved a U.S.-Russia treaty to protect polar bears from over hunting by native populations and creates a commission to study the loss of Arctic sea ice. Due to melting sea ice - polar bears sometimes drown swimming the increased distance between ice islands as they search for food.
This treaty was prompted by dwindling numbers of polar bears. The World Conservation Union (WCU) of Switzerland estimates the number of Arctic polar bears has decreased from 25,000 to 20,000. It is estimated that 15,000 polar bears live in Greenland and Norway - while 5,000 live in Alaska, Russia and Canada. Documentation of a defrosting Arctic came in 2004 in the Arctic Climate Impact Assessment (ACIA). The ACIA was an unprecedented four-year study by an international team of 300 scientists.
Support for polar bears being listed as endangered made headlines when three groups took legal action in 2005. The Natural Resources Defense Council (NRDC), the Center for Biological Diversity, and Greenpeace, filed suit in U.S. courts to prompt placement of polar bears on the Endangered Species list.
Eating High on the Food Chain
Bioassays of the Arctic's wildlife and people have verified the presence of high levels of toxins. Today, the Arctic's indigenous people and predator animals are considered some of the most chemically contaminated life forms on our planet.
Due to location, polar bears and indigenous people eat animals high on the food chain. By doing so - they ingest chemicals that are concentrated in the fat of animals such as seals, whales, walruses, and other animals.
Beluga whales, for instance, serve as a food source for polar bears and indigenous people of the Arctic. While Arctic natives have their long established methods and rituals for hunting whales, polar bears have evolved their own unique methods for capturing beluga whales.
Arctic beluga whales have food in abundance. However, when the Arctic freezes - the whales need to surface every ten to twenty minutes to breathe. Over millions of years, whale pods have developed ways for keeping breathing holes open in the ice. By swimming in a continuous vertical circle to the surface - the whales prevent ice from forming in their breathing hole. When the hole is large - many whales may surface for air at the same time. However, as thickening ice and extreme subzero temperatures reduce the size of the hole - the whales organize themselves to take turns. Eventually, as the long Arctic winter sets in, and the whales become stressed and tired - an opportunity for the polar bear presents itself.
Polar bears wait along the edge of the air hole; when a whale surfaces, the bears leap in and slash the whale with their long sharp claws. Eventually, the weakest and most injured of the whales will succumb and die in the air hole, giving the polar bears a substantial feast.
Even though beluga whale blubber is a high-energy source - it also contains about 80 parts per million (ppm) of the PCB chemical. By contrast - most people have less than 1 ppm. In 1987, high levels of PCBs were found in the milk of nursing Inuit mothers. This discovery caused international concern and raised awareness of the migration of toxic chemicals by ocean currents, sea life, and atmospheric deposition.
The International Threat of Chemicals
Since the Arctic is a region of international interest and overlapping ecosystems, a group known as the Arctic Council was formed. The Arctic Council is composed of members from Iceland; Canada; Denmark; Russia; Sweden; the United States, and Norway.
Studies released in 2004 by the Arctic Council report that "legacy contaminants" such as PCBs and DDT are the dominant chemicals found in Arctic wildlife. DDT and PCB's are considered some of the world's most toxic contaminants. Other Persistent Organic Pollutants (POPs) found in Arctic wildlife and indigenous people include dioxin, PBDEs (flame retardants), and PFOS (stain repellent chemicals).
Flame retardants are found in consumer products such as fabrics, computers, and certain building materials, while stain repellents are found in consumer products such as fabrics used for clothing, furniture and automobile seats.
A paragraph in one study states:
"Environmental contaminants such as persistent organ pollutants (POP) pose an additional area of increased concern for polar bears. Recent documentation of baseline contaminant levels in the circumpolar environment and in key species has dramatically expanded the knowledge of regional presence and levels of these pollutants over the past 10 years. Polar bears, as an apical predator, tend to amplify the bioaccumulation of organochlorine compounds, and are a perfect candidate for studies in evaluating trends. We now know that polar bears inhabiting certain areas of the Arctic exhibit elevated levels of organochlorines, particularly PCB's (poly chlorinated biphenyls) while populations inhabiting other areas have lower levels. Laboratory experiments involving elevated levels of organochlorines have been associated with a range of effects including neurological, reproductive, and immunological changes. Studies continue to evaluate the effect of persistent organic pollutants on essential life functions of polar bears and other marints on essential life functions of polar bears and other marin