Endangered & Threatened Wildlife of the Chesapeake Bay Region:
Excerpt
The Decline of Diversity
If extinction, the irreversible loss of a breeding group of individuals, is a natural phenomenon, one might ask why there is so much concern about endangered species today. Of what possible significance is the loss of the furbish lousewort, the snail darter, or the whooping crane? How is mankind altered by the recent extinction of the Tecopa pupfish? Is life diminished by the passing of the great auk, the passenger pigeon, or the Carolina parakeet?
The significance of modern day extinctions lies in the fact that the overwhelming majority of these plants and animals have been exterminated as a direct result of man’s actions. The normal process of extinction has been accelerated and distorted by the human practices of exploiting natural resources. Man has the ability to alter the environment and disrupt natural ecosystems more dramatically and at a faster rate than all natural forces taken together.
Since the arrival of European settlers at Jamestown in 1607, over 200 species of native flora and fauna have become extinct in the United States, exclusive of Hawaii. Additionally, hundreds of subspecies, including the Eastern elk (Cervus elaphis canadensis), which roamed the Chesapeake Bay region, have declined to the point of extinction because of man’s intervention.
While overhunting was responsible for a large part of the man-induced extinctions prior to 1900, the most prevalent cause of endangerment since then has been habitat alteration and destruction. Among the activities most damaging to native wildlife have been clear-cutting of forests, monocultural agriculture and forestry practices, overgrazing, strip mining, road construction, urbanization and pollution, wetlands drainage, stream channelization, and dam construction….
Biologically, the loss of species or subspecies is equated to the loss of a unique gene pool, which determines the appearance and characteristics of individuals within a population (e.g., the black throat patch of the male Bachman’s warbler). The loss, no matter how small, lessens the diversity of life. It is this diversity that keeps each ecosystem in balance or equilibrium….