Humans have played a major part in the decline of animal species, causing many to be endangered or even into extinction.  Ever since the first humans settled in the Appalachian area (about 20,000 years ago), many animal species have been affected by their activites. The animals that were affected by the first earliest settlers were the American Mastodon, the ground sloth, the immense bison, and the woolly mammoth.  The settlers would hunt these magnificent animals for survival; for clothing, food, etc.  This caused the magnificent animals to eventually become extinct.

The main cause that affect animal species to become endangered or extinct is habitat loss which is caused by human activity and natural disasters.

In the 1700s in the Shenandoah and Blue Ridge Mountain area, there were a great amount of animal species, but when the European settlers first came, they affected the survival of many of those species.  The settlers have done this by clearing land to make colonies, introducing exotic species (that competed survival with the native species), and hunted those native species. This caused many of the animal species to disappear into extinction, or cause their population to decrease.

Another cause that affected animal species to become endangered was the carelessness of hikers in the past years. Many hikers did not know that they needed to be careful where they step because they could completely destroy a whole species pf plants by "trampling" all over them.  This could cause a plant species to become extinct.  Some animal species also depend on certain kinds of plants for food and survival.  The Appalachian Trail started getting crowded during the 60s and 70s because of the hippie era and soldiers recovering from PTSD who came back home from the Vietnam War.  Many of those hikers did not know they were causing animals to become endangered.  Some of those ways were collecting firewood to build a fire; without knowing that they might have gotten the firewood off of an animals habitat. 

Another way is littering.  Many hikers during the 60s and 70s were careless about littering.  Littering can harm wildlife and harm animals.  Many of them could get hurt by a sharp object or worse die from getting strangled by a certain object especially from soda rings. The number of hikers increase every year. There have also been newspaper advertisements encouraging visitors or hikers to come spend a day or more on the Appalachian parks.  It is important for hikers and for visitors to know how they are affecting wildlife and find alternative ways to prevent animals from becoming endangered.

Another way human impact can cause animals to become endangered are recreational areas.  Many recreational areas can disrupt wildlife by harming their habitat.  This is caused by cutting down trees and other natural resources to build recreational areas like roads, cabins, and ski resorts.

Over the years, we have been dependent on fossil fuel (natural gas, gasoline, oil, coal) for our own personal needs such as for transportation by riding in a car, electricity, and burning coal in factories.  But all of these human activities causes air pollution which creates acid rain. Both air pollution and acid rain harms vegetation that animals depend on for food and for survival.