MEPS 564:225-233 Supplementary Material
Sea ice cycle in western Hudson Bay, Canada, from a polar bear perspective
MEPS 564:225-233 | Full text in pdf format
Supplementary material
Supplemental text, tables and figures (.pdf, 3.3 MB)
Video S1
Video S1 shows the daily sea ice concentration (colour shade) in Hudson Bay from two remote sensing products: Bootstrap-v2 (left) and AMSR (right), from September 2004 to December 2009. Although local differences in the sea ice concentration between products may reach over 40%, especially along the southwestern coast of Hudson Bay, the sea ice concentration distribution, melt and freeze pattern are similar in both data sets.
In each panel, the sea ice concentration is overlaid by daily locations of satellite-tracked polar bears (black dots; 1 location per bear per day). The bears were collared in western Hudson Bay during late summer and early autumn, and the collars remained active for 1-2 yr, depending on e.g. battery life. Successful transmission of the GPS locations depended on a successful connection between the collar and the Argo Satellites, therefore the plotted locations suggest that the bears were either on the sea-ice surface or land (shaded grey). For visual purposes, the diameter of the bear locations has been enlarged to approx. 25 km.
Key points to look for in the video:
- Unusual summer melting in 2005, sea ice melts first along the coastal region (video timepoint: 00:00:23-00:00:25). In other years, sea ice melts last along coastal regions
- Polar bear locations on land while sea ice covers the Bay:
- (1) December 2006 to May 2008: newly collared bear prematurely released on land
(video timepoint: 00:01:03-00:01:46) - (2) December 2006 to March 2007: polar bear in den
(video timepoint: 00:01:03-00:01:11) - (3) December 2007 to March 2008: polar bears in their temporary dens
(video timepoint: 00:01:31-00:01:39) - Intermittent locations suggest that underground denning may interfere with satellite
Download the original file here
Video S1 (5.4MB, .mp4)