by Todd Culver

Like all animals, birds need water to survive. First of all, they need to drink. Although some desert birds can extract moisture from their food, most birds must drink water every day.

Birds also use water for bathing, to remove dirt and parasites from their features. And after bathing a bird usually preens — that is, it grooms its feathers and adds a protective coat of oil and wax, secreted by the preen gland, which increases the feathers' flexibility and insulating qualities.

For these reasons, a dependable supply of fresh, clean water is highly attractive to most birds. In fact, a well-designed and carefully maintained bird-bath can attract birds to your backyard that don't eat seeds and won't visit feeders. Providing water for birds can also improve the quality of your backyard bird habitat and should provide you with a fantastic opportunity to observe bird behavior.

What's Wrong With a Good Old-fashioned Birdbath?

Say "birdbath" and most people thing of a concrete basin mounted on a pedestal, the kind usually sold in lawn and garden shops. These look good in your garden, but they aren't always good for the birds. For one thing, they are often too deep. The best birdbaths mimic shallow puddles, which are nature's birdbaths. Concrete baths are also hard to clean; the tiny nooks and crevices must be scrubbed extra hard to dislodge algae and sediment. Finally, concrete basins often crack if they freeze in winter.

Modern Birdbaths

Modern birdbaths are built to mimic natural water sources. When choosing one, look for a basin that can be cleaned easily and has a gentle slope that will allow birds to wade into the water. If you want to make your own bath, you can simply use a garbage can lid, a saucer-type snow sled, or even an old frying pan. If you decide to purchase a bath, consider one made of indestructible plastic that won't break if the water freezes or the dog knocks the bath over. Plastic is easy to clean, too.

The ultimate birdbath is a permanent pool in your backyard. Shallow pools can be dug into the ground and lined with plastic or cement to make them watertight. Landscape around the pool with ferns and native plants and you'll attract many interesting birds. Pumps can be added to circulate the water, allowing you to create elaborate multi-level pools.

Setting Up a Birdbath

When placing your birdbath, try to imitate a natural puddle as much as possible. Position it close to the ground, better yet on the ground. Don't forget to put it where you'll have a good view of the birds.

Also, place your bath in the shade, near trees or shrubs if possible. A shady location will slow evaporation and keep the water fresh longer. And nearby cover will make birds more likely to venture into the water. Birds can't fly well when wet, so they are vulnerable to predation while bathing — cover will allow a quicker escape if a cat or hawk interrupts the bath.

Perhaps the best way to enhance the attractiveness of your birdbath is to provide some motion on the water's surface. Water dripping into the basin catches the attention of birds and ensures that the water remains fresh. Several commercial products allow you to drip or spray water into a birdbath. Or, recycle an old bucket or plastic milk container by hanging it above the bath and allowing water to drip slowly through a pin hole in the basin below.

Keeping the Water From Freezing

Immersion-style water heaters have improved greatly in the last few years and are perfect for use in birdbaths. Most importantly, they're safe to operate. The latest immersion heaters turn off when the water runs dry. Put your heater on a ground-fault interrupted circuit (available from any hardware or electrical supply store) to completely eliminate any danger of electrical shock.

Water heaters are economical as well, operating for just pennies per day. Immersion heaters are widely available wherever feeders are sold.

Recently, articles have appeared in magazines and newspapers around the country recommending glycerin, an alcohol-like chemical, as a birdbath antifreeze. We don't recommend it. Large concentrations of glycerin must be used to prevent water from freezing. In order to lower the freezing point to 15 degrees Fahrenheit, for example, you need a 30 percent glycerin solution. Glycerin is a low-level toxin and has a sweet taste. Birds that ingest large amounts of the substance will experience elevated blood sugar levels, causing hyperglycemia and possibly death. And if the birds bathe in the glycerin solution, it may cause their feathers to mat. Birds bathe and preen to enhance the insulation value of their feathers. Matted feathers are poor insulators and can be fatal in cold temperatures. So use a heater instead!

Maintaining a Birdbath

The key to attracting a large number of birds is to keep your bath full at all times. In the natural environment, most shallow water sources are intermittent. While puddles form after a hard rain, reliable pools are rare and birds will travel great distances to visit them. Keep your birdbath full and you'll be well rewarded. But remember to clean it every couple of days! Never allow the water to become stale or green algae to cover the bottom of the bath.

When you're improving your backyard as wildlife habitat, few things are more attractive than a well maintained birdbath. Provide water thoughtfully and watch the fun.

Reprinted with permission. Copyright Cornell Lab or Ornithology. Bird Bulletin Number 9, Cat. No. 219. September 1992.