A rare bird with an unfortunately unheroic name, the coastal California gnatcatcher is one that has suffered most. The gnatcatcher has lost some three-fourths of its natural habitat, and its remaining population, now dwindled to perhaps 2,500 pairs, is hanging on in shrinking, isolated patches where it is more exposed to predators. It has recently been classified as a threatened species. The coastal sage ecosystem is also home to such endangered species as the kangaroo rat and the quino checkerspot, a large butterfly with a life cycle that makes it especially vulnerable to habitat loss. Before we can talk about change, it is important to understand the many ways that our current patterns of growth hurt wildlife.
Habitat loss is one of the most familiar.
This concept is perhaps easiest to grasp when a complete transformation of the natural landscape occurs. While a few species can adapt to such human-shaped environments, many cannot. All this is at the expense of the many species that depend on more fragile local habitats. This trend is called generalization of habitat, and results in the survival of hardy species such as pigeons, squirrels and raccoons. Standing in a suburban backyard, one may still hear birds singing, but the choir is not nearly as diverse as it was before the subdivisions came and the mature trees were chopped down.