There are many bird species that make large migratory journeys. These trips are meant to fulfill the need to feed and are usually carried out in a south-north direction and vice versa. Sometimes, they travel along many, many miles. They tend to do this in stages, i.e. they stop for a few days to rest, feed, gather strength and go back to their flight.
The species that makes the longest migration is the arctic tern, which breeds in the Arctic during the northern summer and then moves to warmer lands near the Antarctic ice. It travels a distance of between 20,000 and 38,000 kilometers on each journey, depending on the chosen route. They make the journey by flying over the sea, until they reach their destination.
Even though this tern is the species that cover the longest migratory distance, there is another one with a really hard to equal or surpass record: the bar-tailed godwit (Limosa lapponica). This species breeds in North Russia, the Scandinavian peninsula and Alaska. The travel South when cold weather arrives, to New Zeland, Southeast Asia, India, etc. Some individuals travel around 11000 kilometers
This record is not about the covered distance but the lasting of the journey. Our friend, carrying a GPS transmitter, flew more than 12000 kilometers, for 11 days. The bar-tailed godwit took off in Alaska and landed in New Zeland. It is a world record for non-stop bird flight!
You can read more on this article