The bear researchers weigh a tranquillised bear on the sea ice. This is one of many tests that the team carry out once they have darted a bear, each bear is weighed and the information carefully noted. The helicopter is a small single engine machine so a lot of effort is spent saving weight .This ingenious weighing system is an example of this weight efficiency, the pilot and mechanic are expected to lend a shoulder each as four men lift the bear from the ground. Male bears weigh between 300-700 kg, while females weigh 150-350 kg.