I'm so sorry, Kate. It is always sad to lose a hummingbird, no matter what the cause.
Unfortunately, I believe your unusually extreme weather was simply too much for those birds. I know of several cases in New England and the Northeast where warmed nectar and heat lamps were faithfully provided by their hosts, and despite their heroic efforts, their hummingbirds perished from the cold anyway. As I've said on other threads, I think what kills some wintering hummingbirds is not one cold night, but, rather an extended cold; where temps consistently stay below freezing for a high during the daytime and dipping into the teens or below at night for several days on end. These kinds of bitter cold snaps simply wear them down, sometimes beyond recovery even with available warm nectar and warming lights. I fear that this winter is going to take a heavy toll on many wintering hummers around the country, if this kind of weather continues. How sad.
Connie
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