The whooping crane is the largest bird that is native to North America. These birds almost disappeared in the 1800s. By 1941, there were only about 20 cranes alive. In the 1970s, people were worded that these creatures were in danger of disappearing completely. As a result, the United States identified whooping cranes as an endangered species that they needed to protect.
Some researchers tried to help. They began to breed whooping cranes in special parks to increase the number of birds. This plan was successful. There were a lot of new baby birds. As the birds became older, the researchers wanted to return them to nature. However, there was a problem: These young birds did not know how to migrate. They needed human help.
In 2001, some people had a creative idea. They formed an organization called Operation Migration. This group decided to use very light airplanes, instead of birds, to lead the young whooping cranes on their first trip south. They painted each airplane to look like a whooping crane. Even the pilots wore special clothing to make them look like cranes. The cranes began to trust the airplanes, and the plan worked.
Today, planes still lead birds across approximately 1,200 miles (1,931 kilometers), from the United States-Canadian border to the Gulf of Mexico. They leave the birds at different sites. If a trip is successful, the birds can travel on their own in the future. Then, when these birds become parents, they will teach their young to migrate. The people of Operation Migration think this is the only way to maintain the whooping crane population.
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