Although environmental concern is rising in the public consciousness, much of the current city planning and policy-making processes remain anthropocentric.  These policies are of fundamental importance, because the spatial pattern of development and the way areas of natural habitat or other "green space" is spread around the urban mosaic are long-term decisions that determine persistence levels of birds, and biodiversity in general (Marzluff 2001). Architect William McDonough's idea that we should build in harmony with nature, and that a building's sustainability should be judged not only by its energy use and materials, but also by the number of birds that can be heard singing immediately outside, is a shift towards a biocentric paradigm. 

        Many scientists and policy makers already consider birds to be important signals of urban ecosystem health, and as indicators of the level of biodiversity (Marzluff 2001). Birds are familiar, enjoyable, and important to millions of people.  However, birds have strong powers of dispersal, and they may be found in a wide variety of landscapes, simply because they can fly over the unsuitable habitat.  The fact that a bird may be heard singing outside a building does not in itself show that the building is sustainable according to McDonough's ideal; for the building to truly be sustainable, the birds should be present over an extended period of time, and they would need to be able to live in the surrounding landscape, not just fly through it.  Species counts to measure bird abundance should be performed at the building site over an extended period of time, similar to Audubon Society bird counts.

       The clearing of forests and other kinds of natural habitat cause changes to the environment along the edges of the remaining natural habitat.  There may be changes in light levels and understory vegetation beneath a forest canopy, in soil and air moisture, and in predation levels for some species.  These changes are known as edge effects, and the sprawling form of development that is the norm in the United States and many other countries has sliced through the natural vegetation so extensively that at the landscape level, most areas containing development are now primarily "edge habitat" (Lenth 2006).

       On the micro level, each individual building is associated with an effect zone (Marzluff 2001).  A building-effect zone with respect to birds could be a function of human activity, noise, free-ranging pets, and changes in light levels and air composition compared to habitat prior to construction.  Effects from building might cause avoidance in some species, whereas species that are tolerant of human presence may benefit, and simply retaining songbirds near a building is not enough for the spirit of McDonough's idea, if all the birds are synanthropic.

       Population declines caused by reductions in nesting success are associated with habitat fragmentation.  Many studies have found brood parasitism by brown-headed cowbirds to take heavy toll on the reproductive success of songbirds near habitat edges (Miller et al. 1998, Robinson 1995).  The study by Robinson observed cowbird parasitism in most wood thrush nests when landscapes had less than 55% forest cover. He concluded that parasitism and predation on wood thrushes, tanagers, hooded warblers, ovenbirds, and Kentucky warblers were so high in the most fragmented forests, that they may be considered population sinks, and the only reason they persist in fragmented areas are that larger regions of unfragmented forest remain.  These source-sink metapopulation dynamics caused by development are not consistent with McDonough's vision of building in harmony with nature.

       Even if a section of forest is removed for a building, strategies such as leaving as much existing vegetation as possible, and adding native fruit-bearing plants to the landscape, can help keep birds.  It is important to leave snags (dead trees) whenever possible, because of their importance as shelter for cavity-nesting birds, and as an insect food source (Blewett and Marzluff 2005).  The selection of landscape plants is important, because different plants attract different bird species, and exotic plants can attract synanthropic bird species to the exclusion of natives.  We conclude that designing a landscape in accordance with the spirit William McDonough's idea would require leaving habitat and planting the landscape to attract birds, with special consideration for natives.

Click here for an extensive list of landscape plants and the birds that each attracts.