To increase bird diversity in your backyard, enhance your property by adding a water source, a roost box (try building your own!), or a supply of nest material. As well as improving life for your local feeder birds, you'll increase the chances that species that normally don't visit feeders will set up home nearby.
Trying to make your backyard more attractive to birds? Just add water! Birds need a dependable supply of fresh, clean water for drinking and bathing—few things are more attractive to them than a well-maintained birdbath. In fact, a birdbath in your yard may attract birds that don't eat seeds and wouldn't otherwise come to your feeders.
Carolina Wren. Maria Corcacas © Cornell Lab of Ornithology
Traditional concrete birdbaths sold in garden shops make nice lawn ornaments, but they aren't the best type for birds—they're often too deep, glazed ones may be too slippery, and they’re often hard to clean. Also, they may crack when the temperature drops below freezing. The best birdbaths mimic nature's birdbaths—puddles and shallow pools of water in slow streams; they’re shallow with a gentle slope so birds can wade into the water. Look for one that won't break and is easily cleaned.
You can make your own birdbath using a trashcan lid, saucer-type snow sled, shallow pan, or old frying pan.
Setting up your birdbath
Birds seem to prefer baths that are set at ground level, where they typically find water in nature. While birds are bathing, they are sometimes less wary than is safe, and if their feathers get soaked, they can’t take off or fly as quickly as normal, so cats pose a very serious danger. If you have a cat, please keep it indoors. If cats are at all likely to be lurking in your neighborhood, make sure there is a fairly wide open area between your birdbath and the nearest thick shrubbery, so birds have a better chance to detect and get away from a pouncing cat in time.
Place your birdbath in the shade if possible, to keep the water cooler and fresher. Nearby trees also provide branches on which they can preen.
Clean sand or gravel on the bottom will provide more secure footing. Arrange a few branches or stones in the water so birds can stand on them to drink without getting wet (this is particularly important during freezing weather).
The water should be no deeper than 1/2 to 1 inch at the edges, sloping to a maximum of 2 inches deep in the middle of the bath.
One of the best ways to make your birdbath even more attractive is to provide dripping water. Many birds find the sight and sound of moving water irresistible. You can use a commercial dripper or sprayer, or make your own by recycling an old bucket or plastic container. Punch a tiny hole in the bottom, fill it with water, and hang it above the birdbath so the water drips into the bath.
Drinking water entices birds year-round, but keeping it ice free in winter is not as critical as many people believe. Birds have several physiological mechanisms for conserving water, and can usually get plenty from snow or dripping icicles. Electrical birdbath heaters may not be justifiable in light of the problems birds face from electricity production; also, if the air temperature is cold enough to make the water steam, heated birdbaths may pose an immediate danger to birds. On freezing days, birds should use baths for drinking only—not bathing. A network of sticks over a birdbath, holding birds above the water and make bathing uncomfortable, should prevent problems.
The simplest and probably the safest and most environmentally conscientious way to provide water in winter is to set out a plastic bowl at the same time each day, and bring it in when ice forms.
Eastern Bluebird at heated bird bath. Jo Anne Doyle © Cornell Lab of Ornithology
If you do want to keep a birdbath ice-free during sub-freezing days, you have several choices. Manufacturers now offer birdbaths with built-in, thermostatically controlled heaters. Immersion heaters are also available at most places bird feeders are sold. Most new models turn off if the water in the bath dries up. A less expensive alternative is a light bulb set in a flower pot under the water basin. The light bulb will provide enough heat to keep the water from freezing. Ideally, plug your heater into a ground-fault interrupted circuit (available from hardware or electrical supply stores) to eliminate the chance of electric shock.
Never add antifreeze to the birdbath—it is poisonous to all animals, including birds. Some people use glycerin as a makeshift antifreeze in birdbaths, but we do not recommend it. Glycerin is a low-level toxin—if birds drink too much, it raises their blood sugar so much that they may die. Furthermore, when birds bathe in glycerin-spiked water, their feathers can become saturated and matted, providing poor insulation and leaving them susceptible to hypothermia.
Maintaining your birdbath
When the temperature is above freezing, it’s a good idea to keep your birdbath full at all times to attract the widest numbers and variety of birds. But to provide a safe drinking and bathing environment, it’s critical to change the water every day or two. Bathing birds may leave behind dirty feathers and droppings, making the bath increasingly unsanitary for other birds. Grackles often drop their nestlings’ fecal sacs into birdbaths, another cause of filthy water. Algae grows much more quickly when the water isn’t cleaned frequently. Also, the species of mosquitoes most likely to transmit West Nile virus often lay their eggs in bird baths. By frequently changing the water, we don’t give the eggs time to hatch or for the larvae to emerge.
If algae does start to grow, you should thoroughly clean the bath with a stiff scrub brush and running water.
BirdNotes--Providing Water for Birds
Download this free PDF document for additional information.
Birds only nest during spring and summer—their breeding season. But during the rest of the year, cavity-nesting birds often use these same boxes for shelter at night, particularly in winter? Sometimes more than a dozen birds will pile into a single box to conserve heat. But nest boxes are far from ideal for overnight roosting. They are usually too small for a group. Plus most birds need to perch or cling while roosting, but nest boxes have no perching surfaces inside.
Diagram to make a roost box from a sheet of wood. You'll find full directions here
You can help your backyard birds keep warm overnight with a specially designed roost box. Any backyard favorites that typically nest in boxes—bluebirds, chickadees, titmice, nuthatches, and small woodpeckers—may seek refuge in it.
Roosting boxes differ from nest boxes in several ways. A good roost box is designed to prevent the birds' body heat from escaping, so, unlike a nest box, it has fewer ventilation holes. Also, its entrance hole is near the bottom of the box so the rising warmth doesn't escape.
Inside a roost box there may be several perches made from small wooden dowels, staggered at different levels. The inside front and rear walls may be roughened, scored, or covered with hardware cloth so that woodpeckers can cling to them. A hinged top allows easy access so you can clean the box.
An entrance hole about 2 inches in diameter will admit most small birds, but to exclude aggressive starlings reduce the opening to about 1 1/2 inches. Larger woodland birds, such as flickers and screech-owls, need a 3-inch entrance hole.
Mount your roost box on a metal pole or a wooden post, and attach a metal baffle below the box to keep predators out. Place the box in a sheltered spot, out of prevailing winds. South-facing boxes receive the most warmth from the winter sun.
Roost boxes can be purchased from various manufacturers. Look for them anywhere nest boxes and bird feeders are sold. To build-your-own roost box, plans and instructions can be found here.
Most birds build some kind of structure to contain their eggs and nestlings. A bird's nest may be as simple as a depression on the ground such as made by a nighthawk, it may be a hole in a tree excavated by a woodpecker, or it may be an elaborate pouch-like nest woven by an oriole. The most familiar nest type is a cup-shaped structure made of vegetation and sometimes mud. Often, the outer layers are of coarse material lined on the inside with softer or finer material. Depending on the species, cup-nesters may hide their nests in trees or shrubs, build them on the ground, or place them in nest boxes or tree cavities.
If your yard has safe nest sites and adequate construction material, it will be more attractive to birds, including those that don't visit feeders.
Fallen leaves and twigs left un-raked make excellent nest materials for many birds. Providing nooks in your backyard where this untidy debris can collect provides a variety of material for the birds to check out when they are building nests. They may even pick through your compost pile looking for suitable nest material.
You can also put out concentrated stashes of nest material. It can be natural materials like straw, small sticks, and twigs, or manmade materials such as yarn and string. Try putting out any combination of the following:
- Dead leaves
- Dry grass (make sure the grass hadn’t been treated with pesticides)
- Yarn or string—cut into 4- to 8-inch pieces
- Human or animal hair (especially horse hair) (use short lengths—no longer than 4-6 inches long)
- Pet fur (Never use fur from pets that received flea or tick treatments)
- Sheep's wool
- Plant fluff or down (e.g. cattail fluff, cottonwood down)
- Kapok, cotton batting, or other stuffing material
- Bark strips
- Pine needles
- Thin strips of cloth, about 1 inch wide by 6 inches long
Among the materials birds occasionally use in their nests are snake skins (especially favored by Great Crested Flycatchers), plastic strips, cellophane, and aluminum foil. Many small birds, including hummingbirds, use spider silk in nest construction—it holds the other nesting materials together while making a tiny nest stretchy enough to accommodate growing nestlings. Providing a safe environment for spiders will enhance nesting opportunities for these birds. Barn and Cliff swallows, phoebes, and robins use mud to construct their nests. You might consider creating or keeping a muddy puddle in your garden for them.
Dryer lint from synthetic fibers becomes crumbly after it's rained on and dries. Some laundry detergents and fabric softeners may leave harmful residues. We don’t recommend offering dryer lint.
How to offer nest material
Place nesting materials, such as twigs and leaves, in piles on the ground—other materials, too, if they won't blow away.
- Put fluffy materials, hair, and fur in clean wire-mesh suet cages, or in string or plastic mesh bags. Attach them to tree trunks, fence posts, or deck railings. The birds will pull out the material through the mesh holes.
- Push material into tree crevices or drape it over vegetation.
- Put material into an open-topped, plastic berry basket (such as strawberries are sold in).
- Some manufacturers sell spiral wire hangers especially for putting out nest material. (One type looks like an oversized honey-dipper.)