Scientists have been surprised and impressed with the long-distance travel of a bird recently, a common cuckoo (布谷鸟) which flew from southern Africa to Mongolia.
Onon is a common cuckoo. It’s one of 5 cuckoos who were tagged last summer in Mongolia, far to the north of China. Though cuckoos originally came from Africa, until recently scientists weren’t sure that cuckoos from Mongolia flew to Africa for the winter.
In June, 2019, scientists attached tiny trackers to five cuckoos. These satellite tags allowed the scientists to follow the movements of the birds on a map. Sure enough, Onon spent the winter in southern Africa — in Zambia.
This spring, Onon returned to Mongolia, amazing scientists once again with his long-distance flying. In just a couple of months, Onon flew more than 12,000 kilometers. It crossed 16 countries, flying at an average speed of 60 kilometers per hour.
Long migrations are common among sea birds, but cuckoos are land birds. “It was one of the longest animal migrations which has been recorded for a land bird,” said Chris Hewson, one of the project’s lead scientists.
At times, Onon stopped for a few hours or a few days. But some of the long stretches, like crossing the Indian Ocean, had to be done without stopping. The birds have to travel through strong winds and storms, make sure they find enough to eat, and avoid being eaten themselves.
Luckily, cuckoos seem to have a good sense of weather patterns, allowing them to fatten up as much as possible right before they leave. They also seem to be good at finding helpful winds that allow them to travel long distances without getting too tired. Still, flying such long distances isn’t easy. Onon is the only one of the five tagged cuckoos who made it all the way back to Mongolia.
32. Why were satellite tags attached to five cuckoos?
A.To make them safe. | B.To position the birds. |
C.To draw a detailed map. | D.To observe them in winter. |
33. How did scientists feel when knowing Onon returned to Mongolia?
A.Delighted. | B.Astonished. | C.Puzzled. | D.Annoyed. |
34. Why is crossing the Indian Ocean mentioned?
A.Because it is very dangerous. | B.Because it is well-known. |
C.Because it is a place to go. | D.Because it is rich in food. |
35. What’s the last paragraph mainly about?
A.Cuckoos’ advantages. | B.Cuckoos’ senses. |
C.Cuckoos’ habits. | D.Cuckoos’ will. |