Hawks and other large birds need flight cages in order to exercise and maintain a healthy body weight. Most avian flight cages are built outdoors because of space restrictions. It is important to check zoning and permit requirements before beginning any building project. Check with local officials about requirements to avoid costly fines.
Choose a location that is large enough to support a flight cage aviary. A hawk with a 4-foot wing span needs a flight cage at least 8 feet wide by about 10 feet long and 8 feet tall.
Map out a design of the aviary. The bird will need shelter inside the flight cage to get out of the sun or bad weather. The aviary entrance should have double doors to prevent accidental escape, meaning the outside door opens to a small enclosure with a second door to the aviary.
Determine the amount and type of materials needed. The flight cage should be made of heavy duty wire or chain-link fence. The shelter can be made of wood, but the frame of the main structure should be metal. Fence poles work well as framing material for the flight cage. The floor of the aviary should be poured concrete, brick or stone tile to prevent intruders from burrowing into the enclosure.
Measure and stake out the corners of the aviary. Use a post hole digger to sink corner poles 12-inches into the ground for stability. Use fence pole connectors to secure cross pieces at the top of each corner pole to complete the pole frame.
Cover three sides and the top with chain-link fence by securing it to the poles with fence wire. Lay the flooring, too.
To complete the shelter and close the other end of the aviary, use 2-by-4-inch boards to frame two walls large enough to fit the open end of the aviary. Leave space in each wall for a door. Attach the two walls to to make a 4-foot-wide room. Attach one wall to the corner and top fence poles using fence wire.
Use plywood to complete the walls and ceiling, install both doors. Leave an opening in the wall attached to the aviary for the hawk to be able to enter the shelter. Divide the shelter into two floors using chain link fence. The fence will allow the hawk's waste to fall to the ground while preventing the hawk from accidentally escaping through the door.
Inside the flight cage, provide ample sized food and water dishes and plenty of large perches. Large tree limbs with many branches can be sunk into concrete to create an artificial tree. Cover the floor with sand or wood chips for easy cleaning. Use the extra space on the ground level of the aviary's shelter to store rakes, buckets and other cleaning materials.
Aviaries that are in plain view of or easily accessed by the public should have locking doors to prevent unauthorised entry.