While a concrete bird bath is intended to provide a place for birds to bathe and drink throughout the year, it doesn't always work out that way. When temperatures dip below the freezing mark, any water in the bird bath turns to ice. For some concrete bird baths, the expansion of the ice creates pressure that can result in chips or cracks. Winterizing the bird bath prevents such damage.
Two-Piece Bird Bath
Pull the plug on the bird bath---if it is so equipped---to drain it, or carefully tip the basin to allow it to drain. Dip the water out with a small container if the basin is too heavy to tilt when filled.
Turn the concrete basin over and place it, upside-down, on top of the bird bath pedestal. This will prevent it from filling with water and freezing during the winter.
Leave the basin inverted on the pedestal until all dangers of freezing weather are over for the season.
One-Piece Bird Bath
Drain the bird bath basin by pulling the plug or dipping out the water with a small container.
Fill the basin with burlap bags or blankets to protect it from condensation that may form during the winter season.
Cover the entire basin with a large piece of heavy-duty plastic. Gather the extra plastic around the base and secure it with twine.