If you see birds flying away from your area, it could indicate that either a storm or tornado is on its way, a new study suggests.
Researchers at the University of California, Berkeley, University of Minnesota, the University of Tennessee and the U.S. Geological Survey found a link between fleeing birds and occurrence of storms and tornadoes. They observed the behavior of 20 golden-winged warblers in the mountains of eastern Tennessee and noticed that they flee at least two days before an intense storm arrives.
"It is the first time we've documented this type of storm avoidance behavior in birds during breeding season," ecologist and study leader Henry Streby of UC Berkeley's Department of Environmental Science, Policy and Management said in a press release.
It is long known that birds often alter their routes during migration, but the study is the first to determine that severe weather is one of the reasons. The researchers observed that the birds searched for a temporary breeding site at least 1,500 kilometers (about 932 miles) away from the place where they left, then immediately return after the storm.
Further analysis showed that birds started moving away even if the storm or tornado was still undetected by the instruments used by the weather system. The researchers presume that birds can do that because of their sensitivity to infrared sound that humans cannot hear.
"This suggests that these birds can detect severe weather at great distances," wildlife biologist and co-researcher David Andersen of the U.S. Geological Survey and the University of Minnesota, told Reuters.
"We hypothesize that the birds were detecting infrasound from tornadoes that were already occurring when the storm was still quite distant from our study site," he added.
The findings of the study imply that bird observations in predicting weather could effectively save lives and help people prepare for the severe weather. Another option is the development of instruments that can detect infrared sounds.
"There's growing research that shows that tornadoes are becoming more common and severe with climate change, so evasive actions like the ones the warbler took might become more necessary," said Streby. "It could come at a cost, though, since such actions place added energetic and reproductive stress on populations that are already struggling."
This study was published in the Dec. 18 of Current Biology.
