Like blackbirds, robins, bluetits etc? Obviously always wave at magpies.
I was walking back from the shop today, headphones on, walked past a blackbird pair and just generally said hey guys how's it going, and did a little whistle. As I usually do. A man walking his dog overtakes me and looks into my face saying hello, in a questioning way, looking a bit concerned as if I'm barmy.
Do other people not say hi to birds? Same with random cats, squirrels etc?