5/14/2013 1:02:38 PM
Counting Polar Bears
One of the greatest challenges facing those who work with polar bears is that long-term data sets are lacking on all but three of the 19 populations of polar bears. Nine additional populations have varying degrees of data, but seven are in such remote, logistically difficult areas that knowledge is sketchy at best.
This was less of a problem when the polar bear's habitat was stable, especially after hunting was controlled through the 1973 International Agreement on the Conservation of Polar Bears. But as global warming melts their critical habitat, managers can no longer assume polar bear populations are remaining stable in the most remote areas. Figuring out ways to assess the health and condition of each population therefore is becoming increasingly important.
To address this, a global team of 19 scientists has crafted a long-term monitoring plan that the five polar bear nations are encouraged to use as a framework. While the proposal won't count all polar bears, it takes a targeted approach for a sensible assessment.
The paper titled, "A Circumpolar Monitoring Framework for Polar Bears," was published as an in-depth, 68-page monograph in the journal, Ursus. Dag Vongraven of the Norwegian Polar Institute is the lead author. Other contributors include PBI's chief scientist, Steven Amstrup; PBI Advisory Council Scientists Andrew Derocher and Ian Stirling; and 15 other scientists.
Among the highlights, the authors address:
- Best-practice monitoring strategies for a wide variety of research topics, from population abundance to prey availability—along with why the knowledge is important.
- The recommended monitoring intensity for each of the 19 polar bear populations, recognizing that scientists will not be able to monitor all populations at the same levels.
- The need for high monitoring intensity for at least one population in each of the four sea ice eco-regions; those bears can then serve as indicators for other polar bear populations in the same eco-region.
The complete paper is available on the Norwegian Polar Institute website and is well worth the read.