0 meters into the forest, and 60% fewer birds 10 meters from a clearing than 1 km into undisturbed forest. An interesting item is that they did not find a lower abundance of birds around natural edges, such as interior treefall gaps. Several authors that I have read have suggested that the abundance of birds decreases near an artificial edge due to decreased Nest success. Nest success near edge decreased because of the increase in generalist predators and brood parasites. As mentioned earlier, populations of brown-headed cowbirds, a brood parasite, have increased tremendously as a direct result of human activity, these birds have a negative impact on the nesting success of forest songbirds that nest near the forest edge. Studies show that while vegetational changes may extend from 300-600 meters into a fragment. This makes sense when one considers that although generalist predators such as raccoons, cowbirds, and chipmunks may concentrate their activity near the edge, they certainly also can frequent the forest interior, often to the damage of those species which rely exclusively on forest interior. To reduce how far edge effects penetrate into a natural habitat, a biologist Bernard Harris, proposed a system of long-rotation islands, in which and old-growth center is surrounded by various age stands of timber. This system provides some edge for those species which benefit from it, while minimizing the amount of edge between the old-growth center stand and the surrounding stands. Now, to the final section of this term paper, the role that environmentalists play and some of the reasons that they are trying to save it. Rainforests cover less that two percent of the Earth’s surface, yet they are home to some 40 to 50 percent of all life forms on our planet, as many as 30 million species of plants, animals, and insects. The Rainforests are quite simply, the richest, oldest, most productive, and most complex ecosystems on Ea...
