Since my camera is not capable of photographing most birds, I decided to try my hand at capturing bird calls instead. I spent all day yesterday working out the procedure and trying to edit several audios I recorded last week.
Instructions for Converting Video to Audio
Launch Audacity (you can download Audacity for free) and edit the file as follows:
4a. Trim the beginning and end of the recording. Only leave a 3 sec leader and trailer.
4b. Edit out the noise by using High Pass Filter set to 48 dB, 1000-1500 Hz
4c. Normalize your sound recording so that the loudest sound from your target species reaches a level of -3 dB. By setting the peak level of your recording to -3 dB, you’ll be creating a sound file that is consistent with the thousands of sound files archived at the Macaulay Library. To amplify your recording, go to the “Effect” menu, select “Normalize,” and then change the number in the “Normalize Peak Amplitude (dB)” to -3.0 dB. The minus sign is important, so be sure to include it!
References:
Here's a cool video that shows you how to edit a bird recording using Audacity:
https://www.youtube.com/watch?v=GYqogvHYn28
https://support.ebird.org/en/support/solutions/articles/48001064305-smartphone-recording-tips
It's amazing how much background noise there is that we're seldom aware of. Some of my clips had airplane noise that was impossible to filter out without distorting the birdsong. Today I tried to capture bird calls when airplanes were not overhead, and I had a really tough time of it. Planes fly over Rancho San Antonio literally every few minutes in a constant stream of noise. Today, in addition to the commercial flights in and out of SFO, there were military planes taking off from Moffett Federal Airfield every few minutes (and those guys are LOUD). And in between the airplanes, there were crowds of people, a burbling stream, traffic noise from Hwy 280, and my own footsteps and breathing to filter out. By the time the planes and other distractions faded away, the birds were long gone.
Now I have an even greater respect for birders who record sound, and I'm in awe of those who create those gorgeous photos on the Audubon and AllAboutBirds websites.
I realize my audio clips are not that great, but I'm hoping that the purpose of iNaturalist.org is to record information about the occurrence of species in time and space, and not necessarily about the perfection of photographs and audio clips.
I must be crazy for trying to record bird sounds at Rancho, given all of the above. A secluded place away from humanity would be much better, but this is where I hike & volunteer, so I'll give it my best and hope to improve with time and experience. Also, not many bird observations have been posted in iNat for Rancho, and I know there are dozens of species present throughout the year.
My audio collection:
https://www.inaturalist.org/observations/truthseqr?utf8=%E2%9C%93&q=&search_on=&has%5B%5D=sounds&quality_grade=any
I didn't actually see this woodpecker, but heard the drum. Based on this reference, I'm guessing it's a Northern Flicker (red-shafted):
Reference:
http://www.audubon.org/field-guide/bird/northern-flicker
Original file was 101_2338.mov, a video taken with a Kodak digital camera.
Used Convertio.co to convert *.mov to *.wav format.
Used Audacity to trim “empty” space to within 1 second before and 1 second after drumming. Set Amplification to -3db for consistency with other audio clips.
There was a small flock of Lesser Goldfinches nabbing bugs in an oak tree. They were so small and moving so quickly, I couldn't see them very well, much less photograph them.
Original file was 101_2351.mov, a video taken with a Kodak digital camera.
Used Convertio.co to convert *.mov to *.wav format.
Used Audacity to edit out the roaring airplane noise in the background using the High Pass Filter (Rolloff=48 dB; Cutoff Frequency=1000 Hz). Removed 3 annoying camera clicks. Set Amplification to -3db for consistency with other audio clips.
Reference:
http://www.audubon.org/field-guide/bird/lesser-goldfinch
Western Bluebird family. Both parents were taking turns feeding the babies in a birdhouse.
Original file was a *.mov video taken with a Kodak digital camera.
Used Convertio.co to convert *.mov to *.wav format.
Used Audacity to edit out excessive background noise from airplanes and hikers using the High Pass Filter (48 dB Rolloff and 1500 Hz Cutoff Frequency)
Reference:
https://www.allaboutbirds.org/guide/Western_Bluebird/sounds
Chicks and food delivery at nest
This spotted towhee was sifting through the dry leaves to find bugs on the forest floor. I saw it, but wasn't able to get a photo. Instead I captured a sound track of the mew calls & chips. The crackling sound is the bird sifting through dry leaves.
Reference:
http://www.audubon.org/field-guide/bird/spotted-towhee
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