For me, a long swim is about five successive strokes. I cannot imagine swimming 1 kilometer, let alone two thousand kilometers. Fortunately, I will never have to. If I want to travel from Guam to Okinawa, I can take a plane.
A sea turtle, however, has no choice but to swim the distance.
Recently, a female green sea turtle was tracked by satellite. A transmitter was attached to one of her feet after she laid eggs on a beach in Guam. For five months, nothing was heard from the turtle. When the signal was picked up again, the turtle was grazing on seaweed near the Okinawan island of Kume. (You can see Kume Island from the airport at Naha.)
Five months is a long time between e-mails. It seems that the satellite can only pick up the signal when the turtle surfaces. Five months is also a long time to hold one's breath. It's amazing that there exists a creature who can live underwater and also on land.
In Okinawan mythology, the turtle is the link between worlds--the world of humans and the world of the gods. Among the relics discovered at the sunken pyramid of Yonaguni is a statue of a turtle. That stone turtle is itself a link between two worlds--our world, and the lost world of whoever carved the statue.
Who? Why? And where did they go?