Submitted by Anonymous on Wed, 10/21/2009 - 11:47
  • How do you identify the sex of the bear from a distance? We think the answer may be that males travel alone and females are typically seen with the cubs. Is that right?

  • When you collect a tooth sample (pull out a tooth) what tooth do you pull?

  • What drug do you use for tranquilization? Do you adjust the dosage based on the size of the bear? How long do the bears stay asleep?

  • Do polar bears hibernate? When? Where?

  • Are you noticing a nervousness or skittishness on the part of the bears when they see the helicopter approach? We are especially interested in knowing about this in a return visit (when you approach a bear that has previously been collared)?

Cristina Galvan

How do you identify the sex of the bear from a distance? We think the answer may be that males travel alone and females are typically seen with the cubs. Is that right?Great question! Your guess is one of the ways they can tell the difference between males and females. If a bear is traveling with cubs, it is definitely a female. However, just because it is alone does not make a it male - it could be a female who lost her cubs or who will be reproducing that year. The size of the bear is a clue to the sex. Adult males are much larger than adult females. The other main clue is the gait, or walk of the bear. Males and females have a different walk.
When you collect a tooth sample (pull out a tooth) what tooth do you pull?
The tooth that is pulled is a vestigial pre-molar. It is a small tooth that is not really needed. Remember, that the tooth is only pulled for the first time an adult bear is captured. The purpose of the pulled tooth is to figure out the age of the bear. Each year the bear adds a layer to their teeth, so you can slice it and count the number of rings on the tooth to figure out the age of the bear - much like figuring out the age of a tree.
What drug do you use for tranquilization? Do you adjust the dosage based on the size of the bear? How long do the bears stay asleep?
The name of the drug is Telazol - which is a mix of two drugs, one being Valium. The dosage is adjusted based on the size of the bear. For a 400 pound bear, they give it about 7 mL of a highly concentrated dose. The drug is fairly safe in terms of the amount required for an over dosage - meaning the bears can take a lot of the drug and the only affect is that they stay sleeping longer. They give the bear enough for it to be asleep for 3 hours, but if the surgery takes longer they give it a bit more Telazol so it stays asleep. When they leave they make sure that the bear is just starting to wake up.
Do polar bears hibernate? When? Where?
Polar bears do not hibernate like other bears - meaning they do not go into a den to spend the winter. Actually, during the winter is an easier time for them to find food than during the summer. One of the main things this project is looking at is whether or not the polar bears do a "walking hibneration," meaning do they lower their body temperature and activity during times of lower food availability.
Are you noticing a nervousness or skittishness on the part of the bears when they see the helicopter approach? We are especially interested in knowing about this in a return visit (when you approach a bear that has previously been collared)?
The first time a polar bear sees a helicopter it is either curious and comes to check it out or is oblivious and just goes on with what is doing. The bear that I saw that had never seen a helicopter got up on his hind legs to better check out the helicopter. However, after the bear has been tagged once they are a lot more skittish - they run away from the helicopter. Bears that have been recaptured multiple times have developed techniques to evade the helicopter. For example, when the helicopter is right over them, they just stop running. The helicopter takes a while to turn around so this buys the bear some time to escape. Just like bears you may have encountered in camp sites, they are very intelligent and learn how to respond quickly.