OK, Guys. Even when the temp is down in the -40s and -50s there is still open water lots of places. Warm springs, ground water forcing itself to the top as overflow. Thin ice that can always be broken, to get to the water beneath, and fast running streams that won't freeze. Eating snow is not an option, it takes more energy to melt the snow than you get from the water, especially in really cold climates where the snow is really dry.
The only animal that has trouble finding water when every thing is frozen is man. Or shal I say, some men.