National Park Service


Date of this Version



Published in Weber, Samantha, and David Harmon, eds. 2008. Rethinking Protected Areas in a Changing World: Proceedings of the 2007 GWS Biennial Conference on Parks, Protected Areas, and Cultural Sites. Hancock, Michigan: The George Wright Society.


The National Park Service (NPS) goal is to maintain natural processes (NPS Management Policies 2006, 4.4.2: “Whenever possible, natural processes will be relied upon to maintain native plant and animal species and influence natural fluctuations in populations of these species”). As mentioned, animal populations can be expected to fluctuate under natural conditions. Some would argue that animal overabundance in parks is just part of this natural fluctuation, and this may be the case in some situations. However, if a system is disturbed, flux may be greater—for example, when predators are removed and populations of prey are released from “top-down” control. So I would argue that fluctuations are currently greater than what was seen historically because of the significant anthropogenic influences on these systems. Anthropogenic changes, such as loss of habitat and increase in edge due to human development, removal of predators, and landscape modifications that serve as attractants to congregate animals, must play a crucial role in these fluctuations.With the possible exception of parks in Alaska and in the Greater Yellowstone Area, it is difficult to argue that these anthropogenic influences do not affect animal abundance. Thus, an issue arises: Overabundant wildlife populations need to be managed to minimize negative impacts and return systems to more natural function. Unfortunately, the means to get to this more natural end may not be natural.