Instead of a “water cooler” this is a “water warmer” as I put hot water into the plastic birdbath every morning after knocking out the frozen disc and tossing it into the yard. The mourning doves are the first to land and cluster around the steamy water and take a few sips as soon as it’s cool enough, as the center one is having quite a splash. The other birds come in twos and threes, and it seems everyone gets a drink before it freezes again.
Often I’ll refill it partway through the day. Providing water is in some ways more important than providing food in the winter; birds can nearly always glean a few seeds from just about any plant that emerges from the snow, or even find little insects hidden in the buds of almost any tree or shrub, but when water freezes, everything freezes and they are reduced to trying to eat enough snow for water in their day.
Besides that, winter or summer, birdbaths are always entertaining to watch.