Quiet Songbirds

[Wingnut]

I just heard an expert birder say on the radio that the reason songbirds are quiet this time of year is because they don't want to draw attention of the raptors who are migrating. She said that some birds like finches that continue to sing away usually supplement migrating raptor's diet this time of year. I only caught the tail end of the radio show so I can't ID the birder. Any truth to this.

[cloaca]

No, not really.

The two main functions of song are territory defence and mate attraction.   Most songbirds are doing neither at this time of year, so they have fewer reasons to sing.  Singing adds risk at any time of the year (not just during raptor migration), so it wouldn't make sense for a bird to do it when it isn't needed.