Tracking polar bears in the Beaufort Sea – January 2015 map

Here is the January 2015 follow-up to my post on the July 2013 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 USGS track map for January is copied below.

There are only 6 bears being followed now, which means a few more collars have failed, or the bears have moved out of the area or died.

Figure 1. “Movements of 6 satellite-tagged polar bears for the month of January, 2015. Polar bears were tagged in 2014 on the spring-time sea ice of the southern Beaufort Sea. All six of these bears have satellite collar transmitters. Polar bear satellite telemetry data are shown with AMSR2 remotely-sensed ice coverage for 31 January, 2015.” Click to enlarge. Original here.

Only one of the six remaining Southern Beaufort-tagged bears was in Chukchi Sea territory at the end of January, and she was far off the Russian coast west of Wrangel Island.

Four of the other five females were onshore or nearshore east of Prudhoe Bay in the Southern Beaufort Sea, while the remaining one was just offshore near Barrow; only one hasn’t moved at all (dark purple dot) but the others have moved around a bit.

Unfortunately, without more information, we can’t tell whether some of these nearshore/onshore females have come out of maternity dens early without cubs (stillbirths or cubs died just after birth), were perhaps never in dens to begin with, or made dens on the nearshore ice (and now appear to be changing position due to ice movement).

Compare the January map above to last month’s, copied below (December 2014, described here).

Figure 2. “Movements of 10 satellite-tagged polar bears for the month of December, 2014. Polar bears were tagged in 2014 on the spring-time sea ice of the southern Beaufort Sea. All ten of these bears have satellite collar transmitters. Polar bear satellite telemetry data are shown with AMSR2 remotely-sensed ice coverage for 31 December, 2014.” Click to enlarge, original image here.