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Sound the Alarm:
How Birds Send and Spread a Warning
Scott KiesterElm Fork Chapter
Before We started:Just A Bit if Physics; Pressure Waves and The Waveform
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A Bit More; Amplitude and Frequency
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And A Bit More; Band Width
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And Just One Bit More; Sound Attenuation
I = P / 4 π r 2Let’s just say that alarm are calls made up of lower
frequency sounds that have broad bandwidth which travel further and are absorbed less by solid objects.
And of course there is a glaring exception that we’ll get to a couple of slides from here.
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Sonograms: Sound Made VisibleSonograms are visual representations of bird songs and calls.
Frequency is the vertical axis Time is the horizontal axis. Fox Sparrow Song
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The Seet Call; The Exception to the Rule
American Robin
Carolina Chickadee
Tufted Titmouse
Song Sparrow
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An Interview with Dr. Erick Greene Courtesy of The Cornell Lab of Ornithology
Alarm calls can travel at speeds exceeding 100 miles per hour, giving birds advance warning to take cover.
Dr. Erick Greene says it’s a wonder predators ever beat the system. “It’s really hard to be a hawk. You’re hunting and flying around, trying to find your dinner, and yet there’s this bow wave of information that travels out in front of you faster than you can ever fly.”
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Alarm Calls of Some Common Texas Birds
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Northern Cardinals
A typical “TINK” alarm
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A typical Chip Contact call
American Robins
Peek and Tut alarmsto warn of a ground predator; possibly a cat It is often heard near nests
The Seet Call warning of a flying predator
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Northern Mockingbirds
The “Hew” Call;a Harsh SKEEH!
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Downy Woodpeckers
A loud PIK alarm call
A softer slower tempoPIK is typical of abird to bird contact call
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Carolina and Bewick’s Wrens: Scolding from the bushes
Carolina
Bewick’s
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Tufted Titmouse
The Seet Call
Mobbing “chickadee” Call
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Bluejays
“Jeer” Mobbing Call
“Jeer” “Howdy” Call
Cooper’s Hawk Mimicry
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“Pump Handle”; a Low Intensity Alarm Call
https://www.youtube.com/watch?v=VRXhdz8vZ7U
American CrowsShort Caw: A General Alarm Call
Harsh Caw: Associated with Predator Mobbing
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Carolina ChickadeesSeet or “High Zee” Call
A single bird giving an alarm
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Chickadees mobbing a predator
The Chick-a-dee Call:Variations on a Theme
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Helpful FriendsChipmunks
Grey Squirrels
Aerial Predator
Terrestrial Predator
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Suggested Reading/Viewing
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