Winter in Portland. I "have" two Anna's hummingbirds that have been wintering here for the past 8 or so years. It's entirely possible, in fact almost certain they have not been the same birds as 8 years is about their maximum life expectancy with 2-3 being far more the norm. It has always been a male, larger, more colorful (though from my windows they are always back-lit and I cannot see their colors from inside) and a smaller either female or juvenile. (I think of it/her as female but they have never chosen to enlighten or correct me.) The male is larger, is far more adept at the feeders and is aggressive, dive-bombing female,juveniles and other species of hummers to protect his food supply. He is also completely unafraid of me.
This morning it was 20 degrees when I got up. Feeders were frozen. We set out fresh sugar water and will probably be doing the same every morning of the rest of the week. As I write this, the male is feasting on the other side of the window, puffed up to twice his normal size to stay warm. (That warmth bit is a real challenge for them. Their daytime body temperature is 105-8 degrees, right now 87 degrees higher than the outside temperature. Combine that with their body weight of 3 grams (one penny) of fat (not much!). muscle, blood, feathers, bone and organs and you can see they have to be VERY active just to stay alive. I have read that in cold weather, they can live maybe 4 hours without food. Now they can go into a hibernation-like state to save energy where they lower their body temperature to 60 degrees, but they better have a safe place to do it. If a predator approaches, it will be 20 minutes before they are warmed enough to fly. More likely they are a crunchy snack.
And Alphi is back! "Alphi" is my nickname for the male, the alpha hummingbird of the neighborhood. Alphi gets by far the most of the sugar water I put out, but I do it more for the timid female who I worry about a lot more. (We keep three feeders going, two in front and one in back, in front of the windows we use the most. This way, the female can feed at a feeder Alphi cannot see. (Actually, Alphi has been known to hang out at treetop in the front yard were he can see over the house and the approaches to the feeder. I haven't yet seen him dive-bomb over the house but I wouldn't put it past him. Bu that is a summertime activity. Now it's too cold. He just flies in, drinks his fill and leaves.)
In this cold weather, the two birds will drain 2/3s of the sugar water in my 3 feeders in about 3 days. At 2 1/2 oz of sugar water/feeder, that's about 140 grams consumed. Not bad for 6 grams of bird! That's approaching 23 times their body weight per day! And that sugar water is 1 part sugar to 4 parts water by volume. So much sugar, I have to heat it to a near boil to dissolve it all.
Amazing little critters.