Tracking polar bears in the Beaufort Sea: December map

Here is the December 2013 follow-up to my post on the July track map for female polar bears being followed by satellite in the Beaufort Sea by the US Geological Survey (USGS) – Ten out of ten polar bears being tracked this summer in the Beaufort Sea are on the ice.

See that post for methods and other background on this topic, and some track maps from 2012 (also available at the USGS website here).

The track map for December 2013 is copied below (Figure 1).

There has been little change from November: six of the bears that were being tracked in October were still present (down from ten in July) and one bear that went Arctic walkabout in October has returned and is still in the area. The same seven bears present in November were still being tracked in December but did not move very much.

Figure 1. From original caption: “Movements of 7 satellite-tagged polar bears for the month of December, 2013. Polar bears were tagged in 2013 on the spring-time sea ice of the southern Beaufort Sea. All 7 of these bears have satellite collar transmitters.” Note that the dots with the polar bear icons are the end points (end December), while the other end of the string is their position in early December. The same females were present in November.

A few things to note:
The female with the dark brown track is still in the Chukchi Sea subpopulation region. She was in the Southern Beaufort in early October, moved west that month, and has stayed in the Chukchi since then. She may be snug in a pack ice den with newborn cubs or she may be out there hunting: we probably won’t find out until this data is published.

The female with the teal green track (who was on the September map but disappeared during October and returned during November), is still in the area and still well offshore.

The female (light brown) that was on Banks Island at the end of September (Fig. 3) has now moved out of the region altogether — or her collar has stopped transmitting.

Four females are still on or near shore on the north coast of Alaska, east of Barrow. Some of these bears may have been pregnant when collared in July and could be in dens now with newborn cubs.

One bear (light green) has moved west from around the Tuktoyaktuk region in the eastern (Canadian) Beaufort towards Kaktovik.

So – not much change from November (see Fig. 2 below) but interesting nonetheless.

Figure 2. Tracks for the month of November, 2013. Note that the dots with the polar bear icons are the end points (end November), while the other end of the string is their position in early November.