dr. todd atwood tranquillize the bears, collecting samples. studying how climate change is affecting these bears. >> friction, i think. traction. those beautiful claws. >> we spend about 45 to 50 minutes with each bear that we capture. we collect a variety of samples, body measurements so we can see how changing through time. probably right on the cusp of being an adult. and we gave him seven cc's, which is the standard dosage for a bear of this size. i think the most surprising thing for me personally has been the complexity of their behaviors. we've seen them department to some pretty dramatic changes in the ecosystem. we're seeing them use habitats to the extent that we didn't expect. we're seeing them switch to certain food items that we didn't expect them to switch to. we can see hair samples and relate it to how the environment has changed. to see if the changes are causing an increase in stress levels. currently, they are a vulnerable species meaning they have a high risk of endangerment in the wild. >> looking for polar bears is about