Google is failing me - BESIDES OWLS what birds fly the most silent? Forcing results to exclude owl results just gets me rankings about the quietest chirps and noises and such but not flight. I wanted to read about how each flies so quietly and see if they evolved different methods or similar. ? Answered
I realize owls are apparently for sure the #1 quietest flyers and seemingly by a wide margin, but I can't find even the smallest scrap of information on what other species might come anywhere close. Not even hints or shitty sources, straight nothing related.
Hopefully someone here already knows more about the topic and can point me in the right direction.