Source: Audubon magazine https://tinyurl.com/4kzfkjy6
A new study suggests that migratory birds have a kind of built-in GPS that helps them navigate the world, even when they’re far from home.
By Rachel Fritts
March 04, 2021
The birds were getting restless. It was 2018 and fall was in the air, triggering their instinct to leave Austria for sub-Saharan Africa. Problem was, these Eurasian Reed Warblers were somehow starting out in entirely the wrong place, in Neftekamsk, Russia—or so they thought.
In reality, the birds were at the Biological Station Lake Neusiedl in Illmitz, Austria, very close to their summer nesting grounds and more than 1,600 miles from Neftekamsk. An international team of researchers had exposed the reed warblers to an electrical field that mimicked the geomagnetic signature of the Russian city to see how they would respond. Apparently convinced by the scientists’ trick, the birds tried to fly back toward their typical migratory route.
The study, out last month in Current Biology, provides the first direct evidence that migratory birds can use Earth’s magnetic field to extrapolate their position and get back on course, even when they are blown far afield. “It shows what an important cue this magnetic field must be to them,” says Richard Holland, an animal behavior researcher with Bangor University in Wales and co-author of the study. “Despite everything else still telling them they’re on their normal route, they react as though they’ve been displaced two and a half thousand kilometers to the northeast.”
Read more at: https://tinyurl.com/4kzfkjy6