Arctic Biodiversity Trends 2010

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Arctic Biodiversity Trends 2010

Indicators at a glance Species

Polar bears Indicator #01 PAGE 26

Estimates of polar bear populations made in 2009 indicate that of the 19 recognized polar bear subpopulations, only one is currently increasing. Of the remaining subpopulations, three are stable, eight are declining, and seven have insufficient data from which to detect a trend. As polar bears are fundamentally dependent upon sea ice, increased fragmentation and loss of sea-ice habitat as a result of climate change is one of the greatest conservation concerns for this species. Pollutants entering the Arctic via long-range transport are another issue of concern for this top predator as contaminant loads are increasing in some populations.

Indicator #02 PAGE 29

Wild reindeer and caribou

Wild reindeer and caribou have declined by about 33% since populations peaked in the 1990s and early 2000s. While some of the smaller populations are either stable or increasing, the majority of the large herds are in decline. The major stressors contributing to declines vary between herds but climate is an important factor for many herds. For more southern herds, increased human activity and industrial development are of particular concern. The broad spectrum of changes occurring across the tundra environment may delay or slow the recovery of some herds, and some herds may disappear altogether.

Indicator #03 PAGE 32

Shorebirds – red knot

Of the six subspecies of red knot, three are in decline and two appear to be declining, while the trend for the sixth subspecies is not clear. Although the red knot is not yet considered to be threatened globally, it is a long-distance migratory species dependent on a limited number of stopover and wintering sites, and is particularly vulnerable to habitat change along its migration routes. Climate change may be beneficial to this species in the short term if there is an earlier snowmelt and more food is available but ecosystem changes over the longer term may result in a loss of Arctic breeding habitat. The decline in red knots is representative of the overall declining trend in waders.