Just fascinating that researchers can even do this:
“The researchers temporarily attached the small “flight data recorder” to the head of nesting female frigatebirds. The birds then carried the recorder during non-stop foraging flights lasting up to 10 days and 3,000 kilometers. During this time, the recorder registered the EEG activity of both brain hemispheres and movements of the head, while a GPS device on the birds’ back tracked their position and altitude.”
The scientists worked from the Galapagos Islands, where
“Like many other animals in the Galápagos Islands, the frigatebirds were remarkably calm and would even sleep as I approached to catch them for the second time.”
And it turns out that “The flight data recorder revealed that frigatebirds sleep in both expected and unexpected ways during flight.” Here’s the story.