Lancaster Sound (LS)

A population size of 2,500 bears was estimated in 1998 using mark-recapture methods. Population is data deficient, but thought to be declining, because of highly selective harvest of male polar bears.

Status table outtake

Size Sea ice metrics Human-caused removals 2010–2014
Estimate /
95% CI
Year Method Change in spring ice retreat / Change in fall ice advance (days per decade) Change in summer sea ice area (percent change per decade) 5-yr mean Last year
Potential Actual Potential Actual
1995-1997Physical capture-recapture-5.6/5.1-7.792.886.68980
See also the complete table (all subpopulations)

Comments, vulnerabilities and concerns

Demographic data are >15 years old. Selective hunting for males in the harvest decreased due to the US import ban and listing under the US ESA. Increase in shipping activities.

Status and delineation

Lancaster Sound subpopulation mapThe Lancaster Sound area. See also the complete map (all subpopulations).

Information on the movements of adult female polar bears monitored by satellite radio-collars, and mark-recapture data from past years, has shown that the Lancaster Sound subpopulation is distinct from the adjoining Viscount Melville Sound (VS), M’Clintock Channel (MC), Gulf of Boothia (GB), Baffin Bay (BB) and Norwegian Bay (NW) subpopulations (Taylor et al. 2001). Survival rates of the pooled NW and LS populations were used in the PVA to minimize sampling errors; the subpopulation estimate of 2,541 ± 391 is based on an analysis of both historical and current mark-recapture data to 1997 (Taylor et al. 2008). This estimate is considerably larger than a previous estimate of 1,675 that included NW (Stirling et al. 1984). Taylor et al. (2008) estimated survival and recruitment parameters that suggest this subpopulation has a lower renewal rate than previously estimated. However, what effect this may or may not have on the present population is not known, especially under changing sea-ice conditions. Currently, the population data are dated, but the population is thought to be stable based on local traditional information.


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