CONSERVATION OF CAVITY-NESTING BIRDS
According to the Breeding Bird Survey data collected and analyzed by the U.S. Geological Survey, some North American cavity-nesting species are showing population declines. Over the past 40 years, the numbers of Prothonotary Warblers, a southeastern bird, have declined 30 percent. The Mountain Chickadee, which breeds in coniferous and mixed woodlands in western mountain regions, has declined 25 percent over the last 40 years. The Brown-headed Nuthatch, dependent on mature forests of the Southeast, has declined 45 percent in the last 40 years.
Even thought these birds are not long-distance migrants facing the hazards of those journeys, they still face obstacles. These species must deal with the emergence of new houses and buildings, with the loss of trees and habitats, with house cats left to wander, and they must battle communication wires and windows.
Natural cavities for nesting can be in short supply.
Birds need to find suitable habitats in which to raise their young. These habitats must provide adequate food sources, water, and enough space to ensure that their young have a fighting chance to survive. While some birds easily adapt to man-made nestboxes and situations, many habitats require conservation measures to ensure they meet the bird’s requirements.
It does no good to set up nests for woodpeckers or titmice, for instance, if the surrounding land does not contain enough trees to support the birds. Trees are both food sources – insects, nuts and seeds—and potential nesting sites. Trees also provide shelter from predators and weather. If all the dead or dying trees are removed, the potential for cavity-nesting species will be greatly reduced.
Bluebird populations experienced drastic population declines in the early part of the 20th century because of the loss of nesting sites in field and orchard habitats and competition with non-native species such as House Sparrows and European Starlings.
Concerned citizens were instrumental in the comeback of bluebirds during the 1950’s and 1960’s. People put up nestboxes and helped to conserve and protect the habitat that bluebirds need.
Thanks in part to these efforts, bluebird numbers substantially rebounded.
Conservation of all critical habitats is necessary to provide an overall healthy environment for all wildlife. As we create bluebird trails and habitats, we need to remember the importance of all habitats for all species of birds.
By Alicia Craig
Senior Manager of
Nature Center For Wild Birds Unlimited, Inc.
Copied from Bluebird Journal of the NABS, Fall 2002, Vol. 24, No.4
|Copyright © 2002-2011 Louisiana Bayou Bluebird Society|