On the opposite side of a field in which we were watching two coyotes prowling we heard the singing of the American Redstart. It had been quite some time since we have seen this unique little black and red warbler so we skedadled over to a thick stand of willows where thought the singing was coming from.

But low and behold, it was not an adult male making all that wonderful noise, it was an immature male hanging out deep in those willows.

Young male American Redstarts have gray-and-yellow plumage, like females, until their second fall. Yearling males sing vigorously in the attempt to hold territories and attract mates. Some succeed, but most do not breed successfully until the following year when they develop black-and-orange breeding plumage.

https://www.allaboutbirds.org/guide/American_Redstart/overview

We had no idea immature males sang so much.