I love discovering new-to-me bird sounds. While going through some sounds files recorded June 10, 2019 (6:50 am), I saw/heard a few scratchy/squeaky calls following the 2 more recognizable Alder Flycatcher sounds. They have appeared on other spectrograms in my recordings but I never knew for sure which bird made the sound represented on the screen.
In this recording below, first, you hear the “song” of the Alder Flycatcher — fee-beer — followed by a breer “call”. Then a quick jumble of calls follow that I had not recognized before today. Listen for the pips, rapid pwee/pweer-like notes, scratchy dzeers, and otherwise squeaky-like notes of the Alder Flycatcher.