During the last 60 years, bluebird
numbers have decreased 90 percent in the eastern United States.
There are four reasons for the decline:
| * |
The
widespread use of insecticides decreases food supplies. |
| * |
Severe
winters increase winter mortality. |
| * |
Changing
agricultural practices create well-trimmed orchards with
no cavity trees for nest sites. |
| * |
Exotic
species competing for remaining nest sites make nesting
even more difficult. |
Finding suitable nest sites is
perhaps the most severe problem the bluebird faces today.
Allowing trees to mature and develop natural cavities takes too
long. A much quicker solution is to provide man-made wooden bird
houses. When bluebird houses are placed in good areas, bluebird
populations increase rapidly.
Put bluebird houses up by the end of February in areas around
open fields, pastures, golf courses, cemeteries, gardens and
large lawns which provide excellent bluebird habitat. These areas
usually provide plenty of insects to eat. Avoid areas where
insecticides are used heavily for two reasons:
| * |
Insects, a
favorite bluebird food, are reduced, and the birds have
trouble finding enough to eat. |
| * |
The insects
left are usually covered with insecticide. Bluebirds may
be poisoned when they eat these insects. |
Place houses 4 to 6 feet above the
ground and 50 to 100 yards apart. Face the houses to the south or
southeast, if possible. Try to select places where trees, shrubs,
utility wires or fences are within 25 to 100 feet of the houses.
Bluebirds use these structures for perches when feeding. These
perches are also helpful to young birds during their first
flights.
If houses are located near woods and brush piles, other species
of birds, such as chickadees, titmice, nuthatches, and wrens,
will use the bluebird houses. These species, like the bluebird,
are welcome additions to the area and should not be discouraged
from using the bird house. These birds are also helpful in
controlling insect populations. It may be possible to get a
bluebird to nest in the same area by placing another house about
10 to 20 feet from the one the other bird is using.