Unknown bird call

[Luci Timblin]

Hi

I recorded this at 11:38 am on Aug 25. I live on Harpswell Neck near Mitchell Field in a wooded neighborhood along shoreline.

I've asked a few people and no one has been able to ID.

Maybe a juvenile that hasn't learned its proper calls?

Thoughts?

Thanks,

Luci

[Anne Swann]

I was trying to ID a new-to- me call last week and it was similar.... it ended up being some kind of warning call! Still unknown small bird was alerting to a Sharp Shinned hawk in its area. The hawk... Juvenile.... was easy to see once I started to look around the unknown caller that was upset. 
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