CaCO3
Songster
Thankfully the crows seem to like the urban area so not as many out in the burbs where my chickens live, but there is a hawk in one of those clips I swear. Btw there is a peregrine falcon that nests on the travelers tower (and has its own dedicated webcam) and I have seen it munching on a freshly killed pigeon. The crows seem to claim the fringe of the city. Kind of like birds of prey Outsiders. The crows are seriously a phenomenon. Been there for years too.