Arctic terns, their overland migration
This 8 October 2018 video says about itself:
The Arctic Tern, the longest known migration known in the animal kingdom.
It was long believed that Arctic terns flew about 22,000 miles (35,200 km) on their journey from the Arctic region to Antarctica and back. Recent studies, however, revealed that the birds actually fly much farther.
Tiny instruments called geolocators were attached to a number of birds. About the weight of a paper clip, these amazing devices revealed that some terns flew an average of 56,000 miles (90,000 km) on the round-trip—the longest animal migration known. One bird flew nearly 60,000 miles (96,000 km)!
Why the revised estimates? No matter where they began their migration, the Arctic terns flew an indirect route. As shown in the illustration, a common Atlantic Ocean route took an S shape. The reason? The birds simply take advantage of prevailing wind systems. During their lifetime…
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