How do birds hear the calls of species of bird other than their own? Is it like background noise that they can talk (sing) over, filtering out everything but the calls of their own kind, like how you can talk over the murmur of a cocktail party until the second somebody says your name? Or is it more like something they consciously observe and work around, like waiting for your turn to speak in a group conversation flitting between several different topics?
Either way: is such communication strategy an instinctive or a learned behaviour? It seems likely that at least part of birdsong communication is gained after hatching because birds from noisy cities are louder than their country cousins (although you wouldn’t know it, to listen out of the bedroom window of my rural home, this morning!).
Just a moment’s curiosity for the morning.
On Planet Earth it said some insects wait their turn to make their noises in the gaps, in the busy rainforest. Don’t know about birds but would bet there are multiple strategies.