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                     Good evening, ladies and gentlemen. Welcome to the nine o’clock Mystery North American. Black bears are shy animals. They are fearful by nature, and will usually run away if they see or hear people. Because of this , it can be difficult for scientists to learn about these animals.

                  In order to study black bears, researchers from New Jersey, USA, catch bears and use drugs to help them go to sleep. Researchers then work out the size and the weight of the bear, take blood to test for diseases, remove a tooth and take it to the lab to find out its age. From these studies, researchers want to find out how many bears live in New Jersey, how long they live, and how many babies they produce.

                   83 But in Minnesota(明尼苏达州), USA, researchers study bears that are completely awake. The bears know the researchers’ voices and they are not afraid of the research team. With the help of a few grapes to keep the bears busy, researchers can touch them to check their hearts, look at their teeth, and do other jobs. Researchers can also walk or sit with bears for hours and make videos to learn about their everyday lives.

                     In both places, the main purpose is the same—to make sure there is a healthy population of black bears. 84 But the research methods and the kinds of information that researchers are able to collect are quite different.

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