Southern Hudson Bay (SH)

Status table outtake

Table comment: Population estimate of 681 is for the Ontario Coast and 110 for James Bay; the estimate uses professional judgment of abundance in unsurveyed areas.

Boundaries of the Southern Hudson Bay (SH) polar bear subpopulation are based on observed movements of marked bears and telemetry studies (Jonkel et al. 1976, Kolenosky and Prevett 1983, Kolenosky et al. 1992, Taylor and Lee 1995). The initial estimate of population numbers came from a three-year (1984–1986) mark-recapture study, conducted mainly along the Ontario coastline (Kolenosky et al. 1992). This study and the more recent telemetry data have documented seasonal fidelity to the Ontario coast during the ice-free season, and some intermixing with the Western Hudson Bay and Foxe Basin subpopulations during winter months. In 1988, a population-modeling workshop suggested an increase in the calculated subpopulation estimate from 900 to 1,000 bears because portions of the eastern and western coastal areas were not included in the area during original sampling. Additionally, the area away from the coast may have been under-sampled due to difficulties in locating polar bears inland (i.e., below tree line). Thus, some classes of bears, especially pregnant females, were believed to be under-sampled. A new analysis of the 1984-1986 capture data produced an estimate for the study area of 634 (390 – 878 95% CI) and for 2003 – 2005, 673 (396 – 950, 95% CI) (Obbard 2008). An additional analysis (Mh Chao implementation of a closed mark-recapture model) of bears in the Akimiski Island area, which is currently included in the geographic designation of the SH, resulted in 70 – 110 additional polar bears. In addition, there are some areas where bears are unsafe to capture. As a result, the abundance estimate for the area currently defined SH subpopulation is approximately 900.