It has been discovered in the past that certain animals benefit mankind. For instance, within the last ten years it was found that venom from vipers in Afghanistan and Pakistan contains a protein, eristostatin, which may stop cancerous tumors from growing and spreading throughout the body. Another example can be found in snails and mussels. Apparently, these creatures are not susceptible to cancer. Naming the causes Habitat destruction is not the only reason for the diminishing number of songbirds, but it is one of the most significant.
Edge is the border between two habitats.
If a forest area is decreased, more room is made for predators in the edge. Therefore, it is harder for songbirds to find a safe home in the remaining forest. Nest predators such as raccoons, skunks, rats and snakes thrive within the edge while songbirds suffer within. Another factor contributing to the songbird decline is cat predation. Many people assume that cats naturally eat birds and that the demise of one or two every now and then is no big deal.