The birds save more energy prior their migration to the south than they consume during the flight itself.
The birds save more energy prior their migration to the south than they consume during the flight itself.
Millions of birds migrate every year to escape winter, but spending time in a warmer climate does not save them energy, according to research by the Max Planck Institute of Animal Behavior in Konstanz, Germany. Using miniaturized loggers implanted in wild blackbirds, scientists recorded detailed measurements of heart rate and body temperature from birds every 30 minutes from fall to the following spring—the first time the physiology of free flying birds has been quantified continuously at this scale over the entire wintering period. The data offer unprecedented insights into the true energetic costs of migrant and resident strategies and reveal a previously unknown mechanism used by migrants to save energy prior migration.
“We never expected to discover that birds gain no overall energy advantage by escaping cold winters,” says Nils Linek, a first author of the study and a researcher at the Max Planck Institute of Animal Behavior. “It was a longstanding textbook assumption that animals spend less energy by migrating to warmer places, but our findings have shown that these savings don’t add up. Rather, the energetics of migration is far more complex and interesting than theory predicted.”
Read more at Max-Planck-Gesellschaft
Image: A wild blackbird being released. (Credit: Christian Ziegler / Max Planck Institute of Animal Behavior)
