Biodiversity and Nature Conservation

Overexploitation and exploration of natural resources and industrial pollution are major threads to the natural state of Arctic biodiversity. Over millennia, biodiversity had always been subject to changes in species diversity with the occasional extinction of local populations. Yet, most of the environmental changes that we see today cannot be described as the natural fluctuations of a dynamic environment. Instead they are short-term consequences triggered by human industrial impact and have important consequences for the Arctic ecosystems, northern societies, heritage, and economy. Any disturbances are of particular concern as Arctic nature is slow to repair itself.

Some Arctic and Subarctic areas are rich in oil and minerals. Exploitation of the natural resources has caused environmental disturbances in Arctic ecosystems and influenced their biodiversity. For example, offshore activities such as seismic exploration, shipping, and construction of offshore production facilities and pipelines may adversely affect marine mammal distribution and numbers through disturbance or direct mortality. There is also evidence that global climate warming is affecting the Arctic climate, with unknown consequences for this fragile ecosystem. Other environmental issues affecting the Arctic include pollution from southern industrial regions and interference with wildlife migration by constructions such as pipelines and roads. Even the impact of human activities outside the Arctic can alter the activity of Arctic key organisms. One example in this case is given by the recent augmentation of snowgeese populations in North America. Recent increases in grain availability in temperate wintering areas have pushed their population numbers beyond their summer carrying capacity, with the result that saltmarsh areas in some regions of the North American Arctic are being destroyed by overgrazing.

Whaling and hunting of other sea mammals are well-known examples of overexploitation of Arctic resources. Massive hunting of marine mammals started in the early 1600s. Historic losses and reductions, mostly from commercial hunting, include the almost total extirpation of eastern Arctic bowhead whales, which were practically driven to extinction between 1600 and 1700. The populations of blue, fin, and humpback whale were drastically reduced between the mid-1800s and 1920s. The same fate met the polar bear in the European Arctic: by the 1900s, the survival of this top predator was seriously threatened throughout the whole area. Many Arctic fish species are at risk from overfishing and incidental capture. Seabirds are also at serious risk of being caught as bycatch. It is estimated that in 1996, 200,000 birds were accidentally caught in nets in Russian waters and more than 11,000 off the Alaskan coast. Generally, the implications of overhunting are both economic and cultural, as aboriginal people depend upon marine mammals as a major food source and as a mechanism for cultural inheritance.

Arctic ecosystems are particularly threatened by persistent organic pollutants (POPs). POPs are very stable pesticides, industrial chemicals, and byproducts. POPs are dangerous because they can be transported over long distances from sources in temperate regions and accumulate to toxic levels in humans and animals within the Arctic food web. The effects of POPs are not fully understood, but reproductive and developmental effects have been observed in Arctic birds. It is also likely that polychlorinated biphenyls (PCBs) and dioxinlike compounds disrupt reproductive cycles in some marine mammals, in particular, polar bears. The uptake of heavy metals such as mercury and cadmium in Arctic biota has also become a significant issue over the past two decades. The increase of mercury in the livers and kidneys of some marine mammals, for example, is probably due to an increase in the global flux of mercury. In northern Eurasia in particular, acidification has major impacts on the diversity in freshwater ecosystems, reducing the number of fish and invertebrate species in many northern lakes. On the Kola Peninsula in northern Russia, pollution from nickel-copper smelters have led to the devastation of entire regions.

The environmental consequences of pollution are not expected to improve in the near future. The biomagnification effects on certain species may well get worse as, for example, some POPs and metals continue to accumulate in the Arctic environment and become concentrated at the highest trophic levels in Arctic food chains. The projected increase and the effects will be of major interest over the next decade. The close link between the people and marine mammals in the Arctic further emphasizes the need to monitor the status of marine mammals in the circumpolar Arctic. The Arctic is intrinsically linked with other global ecosystems in ways that are only partly understood.

In terms of species extinction, it is probable that biodiversity in the Arctic is less threatened than that of warmer latitudes. Worldwide, nearly 26,000 species are threatened with imminent extinction, including more than 2200 vertebrates. Over a thousand species are known to have become extinct in the last 400 years. Hundreds, if not thousands, of others have become extinct without warning. It is estimated that only 1-2% of Arctic mammals and birds are threatened with extinction compared with 10-12% of those in mountain and 35% in lowland rain forest. This is mainly because many plant and animal species are widely distributed within the circumpolar Arctic. In 2000, a total of 14.8% of Arctic land area was protected: roughly 50% of the Arctic land area of Alaska, 20% in Sweden, 5% in Russia, 25% in Norway, 12% in Iceland, 45% in Greenland, 32% in Finland, and 9% in Canada. Legislation and protection are hoped to protect biodiversity and support the integrity of Arctic ecosystems.

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