For parrots with long tails, purchase a cage with sufficient height to accommodate that tail.
Your bird's cage is its most important piece of "furniture." Size is probably the most important factor to consider when selecting a bird cage. It should be roomy enough to allow the bird to extend and flap her wings without coming into contact with the bars. Small birds, such as canaries and finches, should have enough room to fly to and fro, and larger hook-billed birds should be provided with cages large enough to allow climbing and exercise. Birds with long tails, such as ring-necked parakeets, macaws and conures, require cages with sufficient height to accommodate their tails.
Don't always assume that the cage in which you saw your bird in the pet shop is the correct size. Because birds are displayed on open perches in many shops, the cages may be used only for feeding or rest periods, and may not be suitable as long-term housing. Choose the largest cage you can afford and accommodate in your home.
Your bird will share her interior space with toys, dishes, perches, and perhaps a swing, ladder and other accessories. It's also not unthinkable that you may wish to add another bird at some point! Take measurements before purchasing a very large cage to make sure it will fit through your doorway, if it's a welded model. To avoid doorway dilemmas, assemble a "knocked-down" cage in the room where it will be used.
The style of the cage you select will be dictated largely by your personal taste. Rectangular cages are practical, easy to service and clean, and fit comfortably into most homes and apartments. Circular, pagoda, pyramid, "house" and even covered-wagon-shaped cages can be found, although most of the novelty shapes are available in sizes to suit only small birds.
Bar spacing on any cage should be sufficient to prevent toe and limb trapping, but not so wide that birds can stick their heads through them. Check cages with curved or domed tops to be sure that bars do not converge at the center. Welds should be smooth, with no rough edges to injure your birds or your hands when you're cleaning the cage.
A good-quality cage finish will wear quite well if your bird does not actually gnaw on the bars or constantly splash its water. With the exception of stainless steel, all metal is subject to rust, discoloration or eventual corrosion, depending on environmental factors. Painted surfaces may scratch, chip, flake or stain. You should expect to see some wear as your bird uses its beak to climb about. Acrylic cages are becoming quite popular, and this material, too, can become scratched.
The finish on most cages can be maintained quite well with regular cleaning with nonabrasive products, and by wiping away water, droppings and flung food on a regular basis. Never use metal polish on cages, as it can be toxic to birds.
Put your pet's habitat where the bird can observe family activities without being in the middle of a maelstrom. Place the cage away from sources of intense heat or cold, such as windows, radiators, fireplaces, air conditioners and exterior doors. Avoid locating the cage in the kitchen, since cooking fumes and temperature fluctuations can be harmful. The fumes from overheated nonstick-coated cookware can be lethal to birds, so you may want to eliminate pots, pans, and any utensils coated with a nonstick surface from your home.
Do not place cages in direct sunlight unless some shade is available, since birds may become overheated. Be aware of the fact that the air is cooler close to the floor. Place bird cages at a comfortable level. Mount a thermometer on the wall, at cage level but out of beak reach, so that you can monitor actual cage temperature. If other pets reside in the house, be sure the bird's cage is out of range of teeth and claws. Some houseplants can be toxic if eaten, so keep them well out of your bird's reach.
Want to learn more about bird cages?
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