Image: Wikimedia Commons
Even when they find themselves in unfamiliar waters, sea turtles have a remarkable ability to find their way home.
Now, scientists have a pretty amazing theory about their navigational skills; They may be using the sun to set their very accurate internal compasses.
Scientists at James Cook University in Australia tagged 22 turtles, dropped them in waters nearly 20 miles away and tracked their journey home. They witnessed the turtles using the sunrise to orient themselves.
“We didn’t expect that at all,” biologist Dr. Takahiro Shimada told the Australian Broadcasting Corporation. “There’s no studies showing their directional correcting in relation to the sun, but we found something is happening in the hours around sunrise.”
According to Shimada, previous research proves turtles can navigate home from hundreds of miles away, travelling for eight hours at a time before resting for another eight.
“The turtles would change direction when the resting period ended, usually early in the morning,” he said. “One theory is, obviously the sun comes up from the true east, so they may be using the direction of the sunrise to calibrate their internal compass.”
It’s also possible the turtles are seeing things we can’t. Birds navigate using polarized light that reflects when the sun is on the horizon. Turtles may be using a similar system. Shimada said the research team will continue studying their behavior in an effort to totally understand how their sense of direction works.