Natures wonders: how Great Gray owls hunt voles (Introduction)

by David Turell , Monday, December 05, 2022, 17:40 (717 days ago) @ David Turell

The shape of their face allows the=m to hear sounds through thick snow:

https://phys.org/news/2022-11-giant-faced-owls-snag-voles-hidden.html

"Hovering over a target helps giant-faced Great Gray owls pinpoint prey hidden beneath as much as two feet of snow.

"Several of the owls' physical features, especially parts of their wings and face, help them correct for sonic distortions caused by the snow, enabling them to find their moving food with astonishing accuracy, according to a new UC Riverside study.

"While most owls fly straight at their prey, this species hovers just above a target area before dropping straight down and punching through the snow with its talons.

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"A key finding relates to the owls' broad disc-like face, which they use like radar to find food. The fleshy part of our ears works the way their facial features do. An opening under their feathers funnels sound toward their ears, which are located near the center of their faces.

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"Bigger facial discs are more sensitive to low-frequency sounds. With the largest facial disc of any bird, great gray owls are built for hunting voles, their preferred food. Often mistaken for mice, voles have high-pitched voices that get lost under snow cover. However, their digging and chewing sounds beam straight onto the owls' facial radar.

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"'The fact that low frequency sound passes through snow explains the facial disc of this species, because they have better low frequency hearing with such a big disc."

"The group's sonic experiments also demonstrated that snow bends the voles' sounds, creating an "acoustic mirage," which could lead owls astray. By spending a moment directly above their prey, the birds correct for the snow's distortions.

"'The distance the sound has to travel from just overhead is shorter, and there's less snow for the sound to travel through from that spot," Clark said. "This definitely helps the owls land where they need to."

"Great gray owls also have wings that appear to dampen the sound of flying, which may allow them to concentrate on the noises coming from the voles. Among all owls, this species is among the quietest in flight, owing to long, fringed wings coated in thick "velvet." The sound-dampening qualities of these wings may be particularly useful during the hovering phase of the hunt."

Comment: look at the picture to see how broad the face is, with two straight-ahead eyes of a predator. This complex adaptation would require multiple mutations. Not by chance. It had to be designed