What can I do to keep the bird bath ice free?
If you don’t want to invest into a heated bird bath, then there are a couple of little things one can do, to avoid or delay the water freezing. The success rate depends obviously on the outside temperature.
Firstly, one can take the bird bath off the ground and position it in a sheltered but potentially sunny area. Secondly, one could add some natural apple cider vinegar (ACV), which can be given as 0.5% ACV in water or 5ml per litre. One should make sure that a plastic water bath is being used, because ACV is acidic and will corrode galvanised containers. ACV his healthy for the birds and lowers the freezing point a little bit. Thirdly, one could also buy a special type of drinker, which works like a thermos flusk and keeps water longer ice free during the winter, but will also keep water cool during the summer. Also, a floating pingpong ball keeps a bird bath longer ice free too. However, it might take a while for anxious birds to get used to the floating ball.
Last but no least, you might just want to go out and break the ice several times a day, or add some luke warm water.