Avian-Avalanche!
Ask me about scrub jays! Get a chair first though.

As more California scrub jays pair up in my area, I've noticed that; when I see one eating somewhere [say, perched on a branch trying to crack a nut] there's another scrub carefully watching from a higher perch, and when danger is noticed, they might screech, and both fly away... it's quite interesting when these birds do for each other! I'm sure other corvids engage in this lookout behavior, but I haven't seen it firsthand other than with these Scrubs!