Providing water during periods of freezing temperatures is a simple matter of acquiring a bird bath heater. There is the double advantage of hot having to dismantle and store your bird bath for winter, too.
December: Birds (and probably Squirrels)
The winter months give us time to appreciate wildlife in our gardens. Provide food and water and "They will come." Bird food now comes in specially formulated mixes to encourage certain species of birds over others. Read the labels! Also, some bird feeders are designed to work for certain species of birds and not others. There are even squirrel feeders. Do a little research before shopping if you are particular about which birds you feed.