Water can be a valuable resource for birds when it gets cold outside. Sure, there are electrical heaters and fancy devices that aerate the water, but why bother when you can use the sun? If you have a birdbath, now is the time to give it a few coats of nontoxic black latex paint for outdoor use. Let it dry and cure for a few weeks, then place it on the south or southwestern side of your property, where you have the most amount of sun during the day. The black-painted birdbath will absorb the heat and keep water from freezing.