Purple martins are swallows that migrate from South America to North America each year to breed. Many people enjoy listening to their songs, watching their aerial acrobatics and seeing fledglings emerge from their nests. Although purple martins don’t eat mosquitoes, they eat large numbers of many other kinds of insects. For these reasons, many people build martin houses in the hope that the birds will build nests in them.
1 Site your martin house properly. Purple martins won’t nest in houses too near the ground or too near homes or tall trees. Martin houses should be a minimum of 40 feet (12 meters) from homes and trees and 20 feet (6 meters) high.
2 Design your martin house for several nesting pairs. It should have nesting compartments that are completely separated from one another, access holes for the birds, porches to perch on and a gabled roof. Some houses have multiple levels to accommodate more birds.
3 Cut the wood for the floor so it will extend past the exterior walls 3 inches (7.5 cm) on all sides. This creates the porches. You can also attach porches using 3-inch strips of wood.
4 Create several nesting compartments inside using partitions. Each space should be 6 inches (15 cm) tall, 6 inches wide and 6 inches deep.
5 Cut semicircular entrance holes. These should be 3 inches (7.5 cm) in diameter and 1-3/16 inches (3 cm) tall for each compartment. Set the bottom of the hole flush with the porch to discourage starlings and owls from using the martin house.
6 Drill small holes in the “attic” portion of the house to encourage air flow. Cut a thick piece of polystyrene or corrugated cardboard to fit inside the attic so the house won’t get too hot.
7 Build the roof. Make sure it extends past the exterior walls enough to help shield the access holes from rain and give the birds some shade.
8 Assemble the martin house. Keep in mind that you will want to occasionally disassemble it to clean out the nesting compartments. If you use a router to create slots in the partitions, the floors and in the exterior walls, you will be able to slide them together for a tight fit without permanently attaching them with screws or brads.
9 Paint the house white. Never paint or stain it dark colors, although you can paint the trim another light color if desired.
10 Mount the house on a metal pole that has been set in concrete. You may want to add a winch and pulley system that will allow you to raise and lower the house easily so you can check on nestlings or clean the compartments.
S & K Purple Martin House – 10 Family FH10
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