Birds can detect even small changes in barometric pressure, and there’s evidence that they can hear low-frequency sound at great distance—powers beyond human abilities.
Changing Air Pressure Sensitivity. Research has shown that birds’ behavior changes markedly when barometric pressure changes even slightly. But scientists are still debating how birds detect changes in air pressure. It could be that they detect it in their inner ear—as humans do with changes in elevation. (Our ears pop.) Another possibility is that birds sense air pressure changes in huge air sacs that connect to their lungs and fill much of the space inside their bodies. Also, many birds have a Viteli’s organ (also called a paratympanic organ) in the middle ear—which may serve as both a barometer and an altimeter.
Birds can detect much more subtle changes in air pressure than we can, as little as is reflected by a 60-foot elevation change. (Imagine what it would be like working in a skyscraper if human ears popped each time we changed 60 feet in elevation!) When air pressure drops because a weather front is moving through, birds sense that the weather is likely to change for the worse. As the front passes through and air pressure rises, that’s an all-clear signal to birds that we can’t sense.
Hearing Infrasound. Golden-winged warblers fitted with tiny geolocators vacated their nesting territories well before tornadoes passed through the area. Researchers believe that the birds heard infrasound, the low-frequency rumbling of those storms, through the ground, and took evasive and possibly life-saving action.
Get professional advice from the editors of Watching Backyard Birds on making your backyard safe and welcoming for birds during fall migration and beyond. Whether you're new to backyard birding or are a lifelong bird watching enthusiast, you'll find this eBook to be extremely useful.