I don't know Hopefully there won't be a next time but if there is you should try and find a wildlife rehabilatator special.izing in birds. Sorry about the loss! Sarah

oh, I'm sorry you lost a hummingbird! I haven't seen a dead one. was it hanging head-down from the feeder when you first saw it?
I don't know the answers to your good questions.
I guess I thought hummers could go into torpor overnight to survive the cold. is it possible that this bird was in shock or pain, or was sick or poisoned, and not 'in torpor,' as I think of it as a desired or intentional state? do hummers go into torpor after injury or during sickness?
I don't know.
help us out, folks.

Hummingbirds do indeed run out of gas, so to speak, but usually during Migration,and I don't think it's too long before they are back in circulation.I witnessed it last year, but before I could get a camera, his was gone.I believe there feet lock, and don't always keep them upright on Plastic feeders.