I tend to be birding, if only casually, anytime I am outdoors. For those purposes, I do not need binocs because I have learned the gestalt of common bird shape, behavior, sound, and flight patterns. I am far from expert, but better than most casual amateurs. For example, my birding friends can readily ID a flying Cooper's from a flying Sharpie, but I can not. Nor am I any use at all with fall warblers or rarities - I tend to guess for the regulars to be safe.
I have been doing an inventory of my binoculars this weekend. No reason, really. Closet-cleaning. Also because planning a cool birding trip to South Carolina barrier islands this Spring. Turned out I have 13, from handy-dandy minis through mid-range birding binocs to marine very long-distance binocs which I have also used for hawk-spotting (bad idea - it's impossible to find the spot in the sky and the wobble is a problem).
I have to give some of them away.
What I usually have on hand when outdoors for any length of time is one of my minis, but if I intend to do some serious looking my go-to is my Minox 8X32. It's waterproof. They make an 8X33 now, but I don't need that. I bought a binoc harness from Cabelas.
Experts can and do ID pretty much anything with bare eye or with the inexpensive Nikon mini in their pocket, but when you are looking for the one Glaucous Gull in a flock of 2000 gulls, you need more. If you sport a Swarovski you had better be at pro level or you're a poseur. Firearms, cameras, binocs - an amateur like me does not need the best because it's just for fun. I have also observed, over time, that the best talents never need the best kit. I rarely use my good birding scope anymore because of the hassle.
What do you use for birding? (Some wise guy will comment "12 gauge". In a duck blind, I tend to have binocs and a 12 ga.)