I’ve often noticed when I step out of my apartment waiting for a carpool (Mid-atlantic; Maryland), the bird chirp seems to go up into high gear for about five minutes and then dies off to basal levels.
Are birds of different species warning each other that there’s a human on the scene? Here, we have ravens/crows, blue jays, robins, doves, cardinals, and who knows what else.
If so, how are they doing that and why? I imagine there is a specific warning chirp/species call/tone/chirp that within species other species recognize? But why would one species of bird practically care for another? Better the other species is tracked?
Maybe **Colbri **has some insight?