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Journal
Publications
Taylor
M.K., J. Laake, P.D. McLoughlin, H. D. Cluff and F.Messier. 2006. Demographic
Parameters and Harvest-Explicit Population Viability Analysis for Polar
Bears in M'Clintock channel, Nunavut, Canada. The Journal of
Wildlife Management 70(6):1667-1673
ABSTRACT
Polar bear (Ursus maritimus) numbers in M’Clintock Channel,
Nunavut, Canada have decreased significantly since 1972. We used
mark–recapture and recovery data collected from 348 marked polar bears from
1972 to 2000 to estimate demographic characteristics and harvest risks of
the M’Clintock Channel polar bear population. Total (harvested) survival
rates (61 SE) from mark–recapture analysis were: 0.62 (60.15) for cubs of
the year, 0.90 (60.04) for subadults (ages 1–4 yr), 0.90 (60.04) for adult
(age 5 yr) females, and 0.88 (6 0.04) for adult males. Mean litter size was
1.68 6 0.15 cubs with a mean reproductive interval of 2.8 6 0.2 years.
By 6 years of age, on average 0.29 6 0.47 females were producing litters;
mean litter production rate for females aged .6 years was 0.93 6 0.33. We
estimated total abundance to average 284 6 59.3 bears, of which 166.9 6 35.4
individuals were female and 117.2 6 26.4 were male. We incorporated our
standing age and mark–recapture demographic parameters as input into a
harvest risk analysis designed to account for demographic, environmental,
and sampling uncertainty. Population growth rate was 0.946 6 0.038 for the
period 1993–1999. A harvest quota not exceeding 3 bears/year is required if
the population is to increase in the short term. Slightly higher quota
options are available if increased risk and recovery times are accepted by
stakeholders. |
