This is called Foley kids. It’s how sound work was done before everything was digitized into files. Live radio shows and silent movies made use of these artists starting around 1914, the first (known) being Jack Foley who added sound effects to the first “talkie” (the first non silent movie) because microphones of the day couldn’t record ambient sounds and dialog, hence the name.

Not a bad 'best of'. Fuller compilation with all these:
*related=https://videosift.com/video/Sound-Effecting-My-Mom

Best Sound Effecting My Mom has been added as a related post - related requested by noims on that post.

Sound Effecting My Mom!! has been added as a related post - related requested by noims.

I’m not SURE you’re wrong, but that looks like single pane glass which barely muffles sound at all (just like I have in my 70 year old house), and crows are definitely known for learning how to mimic words quite well.

Or perhaps (more likely) this unit has a malfunctioning cpu and its surveillance recordings are getting mixed up with its bird sound effect files and its amplifier is also being overpowered.
Birds aren’t real!

Star Wars spy probe. Just needs the sound effects.

Upvoted for sound effect.

The sound effect made my ice tea squirt out my nose.

Really. They put the screeching bird sound effect in there?

*related=https://videosift.com/video/If-Cardi-B-did-sound-effects-for-Star-Wars

If Cardi B Did The Sound Effects For Star Wars - Episode II has been added as a related post - related requested by ant on that post.

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Awesome video ruined by fake sound effects.

I think the rain was a stock sound effect to make it more dramatic.

http://www.youtube.com/watch?v=0VSEPOG9qSc with Half-Life sound effects!