Living condition
changes
habitat has been destroyed to some extent
Ice began to melt
lack of food
warming water
dangerous
Population
is significantly reduced in recent years
survival rate of polar bears had varied significantly
high mortalitiy
because of
warming climate
Range
may be the main cause of mortality now（Derocher & Stirling， 2011）
Juvenile polar bear have less survived from the hard environment
Environment
Importance
most basic prerequisite for the survival and development of human beings
why
provides the necessary resources and conditions for our survival and development
Protection
Practice
reduces environmental pollution
Significance
curb the trend of ecological deterioration
an important task of the government's social management
raises the public awareness for protecting environment
national policies
sustainable development strategies
Nature
gene flow between local populations of polar bears
a precious specie not harmless to humans
food
primarily seals
ringed seals
beared seals
walrus
beluga whales
seabirds
fish
small mammals
clean carrion
in summer
eats berries or the roots of plants
at the end of spring and summer
go to the beach to get up and take up the minerals and vitamins
eating is affected by the earlier sea ice breakup
influences
population dynamics
species distributions
interactions
a disaster for Artic marine mammals
Hibernation
Local aestivation
Reproduction
Hunting
polygamy
reproduces in the spring
Infant mortality in Canada is about 10 to 30%
Life
自由主题
female bears stay in the cave
convert its subcutaneous fat stored in the body
to produce milk to feed the baby
to provide needed nutrition for their own
Vulnerable to
pollution
poaching
industrial activities
human activities
in Canada
Death
female polar bears and cubs are all dead, which was marked in Ramsay et al. (2011) research
polar bears were killed by human beings when they were pregnant
effect of hungting drug exerts a negative influence on the survival of polar bear
there was no restriction on the hunting for polar bears and the native Arctic Inuit hunt polar bear hunt each year
in the past
hunting for fur clothing
another cause of population decution
Protection
environment protection
restriction on hunting
government policies
diseases
rabies
fatal
is spread in the wild animal and livestock
by
bites
close contact
Climate change
warming climate
Inuit
hunt
sent dead or sick people to the polar bear infested wilderness and waiting for the polar bear to eat
the tradition and culture
3 to 5 months resting period
finds cave to rest
at this time bears are very dangerous
spilling of oil
organic pollutants
polar bears, as top predators, have the risk of accumulating these compounds in the body
nevrous system
reproductive
immune function
starvation
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