Submitted by Anonymous on Thu, 10/22/2009 - 08:32
Forums
Polar Bear Response to Sea Ice Loss

  1. If the sea ice continues to melt, will that change the currents in the Arctic Sea? And if yes, then could this affect the food chain that the Polar Bears rely on?

  2. Is the average mass of the the Polar Bear decreasing due to lack of food? And if so by how much? And which are the most affected, males or females? Do you think that over a period of time the number of cubs will decrease?

Thu, 10/22/2009 - 08:45

Cristina Galvan

Thanks for the questions!1. If the sea ice continues to melt, will that change the currents in
the Arctic Sea? And if yes, then could this affect the food chain that
the Polar Bears rely on?
What a great question! It is possible that the currents could change due
to changes in the temperature and density of the water, which all affect
currents. The currents are related to the food chain - this might
affect the fish in which the seals feed on and polar bears rely on the
seals for the main source of food.
2. Is the average mass of the the Polar Bear decreasing due to lack of
food? And if so by how much? And which are the most affected, males or
females? Do you think that over a period of time the number of cubs will
decrease?
The average mass of the young and the older polar bears is in fact
decreasing. They are seeing increase in the number of cubs of the year
(cubs less than a year old), where as there is a decrease in the
survival rate of the yearlings (cubs that are 1-2 years old). Since the
yearlings are not surviving, female bears are reproducing more often -
hence the increase in COYs. The sub-adults (3-5 year old) are also
decreasing in size.
Survival of the