Hi SS,

Stupor is what I go into when I've had too much Tequila. Torpor is what the hummers go into when it's too cold. They'll be OK, the little ones have been enduring sharp changes in weather for a looooong time.

And yes, vinegar would work great on your fountain.

cc

Here is a link that might be useful: Info

LOL.....knew I was close :-) Thanks for correcting me! They were here just a few minutes ago at the feeder. It's in the 40s but predicted low 30s tonight. Wish I could let them in my sunroom for the night. Good news re vinegar. I knew it wouldn't hurt my dogs but wondered about birds. I have a frog living in it too.......no fish though. Vinegar will be greatly diluted by the time the hummer drank........ss

sallie, I think I misunderstood your question about the vinegar. I thought you were going to clean the fountain with vinegar, but you're wanting to mix vinegar with the water to control algae? It probably won't hurt the birds, but they may not drink it. I'd be more concerned about the frog - they have very sensitive skin (think acid rain).