I don't need to read the weather forecast to know if a storm is coming or not. I just look to see who is gossiping around the bird feeder.
If it's just the usual suspects - the Chickadees, Dark-eyed Juncos, Goldfinches, and other small birds - I know we're good. But when all the big guys and loners start showing up....
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Hairy Woodpecker and Goldfinches |
I know there's a storm brewing!
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American Goldfinches |
But how do birds know a storm is moving in? Scientists have long thought that birds sense barometric pressure, and in 2013 Western University's
Advanced Facility for Avian Research (AFAR)
proved it by putting White-throated Sparrows in a
hypobaric avian wind tunnel. (Wind tunnel for birds? I'm impressed!) When scientists simulated an oncoming storm by dropping the air pressure before dawn, the birds would immediately start eating at first light instead of doing their normal morning preening.
But while birds being able to sense air pressure is really not a surprise, researchers suspect that birds may have another way of foretelling when bad storms are coming...
A couple of years ago researchers were testing whether or not the small
Golden-winged Warbler could carry geolocators on their backs. It turns out they could - and they provided some unexpected but extremely interesting data.
In April 2014, the Golden-winged Warblers had just flown from South America to their breeding grounds in the Tennessee mountains when an incredibly
massive storm started brewing across the US, one that ending up spawning 84 tornadoes and killing 35 people. Two days before the giant storm reached Tennessee - and while it was still over 500 miles (900 km) away - the birds
turned around and fled 1,000 miles back down south to the Gulf of Florida and Cuba to wait out the storm before flying back up north.
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Dark-eyed Junco |
Realizing a giant storm was coming when it was still hundreds of miles away? That's some impressive forecasting! But researchers realized that the Warblers left even before there was any change in barometric pressure, wind speed, or anything else in Tennessee that would normally cause them to flee that early. So how did the birds know a storm was coming so far ahead of time?
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Eastern Bluebird |
Scientists think that the birds must have been able to hear
infrasound waves from the approaching storm. Infrasound, sound where the wave frequency is so low that humans can't detect it, can carry over large distances, and this deep rumble made by far-off tornadoes might have tipped off the birds that something big was coming.
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Northern Cardinal |
Birds predicting oncoming storms by air pressure changes and infrasound make sense.
How about birds predicting earthquakes?
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Downy Woodpecker |
There have long been anecdotes about animals fleeing an area before an earthquake happens. There is now a hypothesis that some migrating birds could predict earthquakes because of their ability to detect shifts in magnetic fields. Before an earthquake strikes, stressed rocks give off clouds of positive electric charge, which generate a magnetic field at the Earth's surface. Do birds detect this, and could a change in migration patterns predict an earthquake? Scientists with the
ICARUS Initiative (short for International Cooperation for Animal Research Using Space) are hoping to find out. They have started tracking migrating patterns of birds and bats by tagging them with ultralight, solar-powered transmitters, and disaster prediction is one of the things they are studying. It will be interesting to see what they find.
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Northern Flicker |
Who knows? Maybe someday instead of watching the Weather Channel for forecasts of impending doom, everyone will just watch the birds.