Design - Project Planning and Management for Ecological Restoration - page 93

FIGURE 6-12. Nest boxes provide immediate nesting sites for many species ranging from small songbirds to
ducks. Patuxent Research Refuge, Patuxent, Maryland. (Photo by Mary F. Platter-Rieger.)
grounds or some other function, those elements that satisfy the requirements of the species must
be present. In many cases, a feature is something that is developed over time. If you have the time,
then you do not need to actively provide it from the initial establishment of the site. However, this
is not typically the case, and you must be resourceful in providing those habitat features.
A good example is cavity nesters, both birds and mammals. Unless there are old mature trees,
rocky outcroppings, or a steep embankment, it is unlikely that a newly constructed site will have
these specific features. The latter two examples can be constructed on-site with fairly routine
methods. However, a tree cavity requires a large tree. Does the tree have to be alive or dead? Does
it have to be a tree? Will the target species use a substitute structure, such as a bird nesting box
(fig. 6-12)? The latter, of course, would require some maintenance, but as an interim solution, this
approach has proven successful for several bird species in the eastern United States. In the western
United States, burrowing owls have benefited from using nesting sites constructed from PVC pipe
and utility boxes. Nest boxes for barn owls have been used with great success along the Sacramento
River in California. These should be considered interim measures until the site can mature. In the
case of the owl, they typically take over holes initially dug by ground squirrels. If no squirrels are
on-site, this interim solution will provide time for the site to develop and a squirrel population to
become established to create future nesting opportunities for the burrowing owl.
Providing these types of interim solutions may be necessary to ensure the continued presence of
the targeted species during restoration activities. Although artificial in many respects, this may be the
best method to allow the species to remain in the project area. If it is likely that the target species may
not reoccupy the site following restoration activity, then these artificial measures will permit the pres-
ence of the species until suitable natural habitat has been created or provided on the project site.