Burgeoning Ungulate Populations in National Parks: is Intervention Warranted?

The issues pertaining to ungulates and vegetation in national parks embody the essence of a broad debate about the purposes of and approaches to park management. Parks have always been thought of as preserves of natural environments, but valued primarily for their recreational and cultural attributes. Manipulation of natural resources to enhance these values was unquestioned. Today parks are increasingly valued for biological attributes, providing remnants of natural ecosystems, reservations for species diversity, and reservoirs of genetic variety. Burgeoning ungulate populations are impinging on some of these values. There is increasing debate about the need for intervention to control native ungulate populations. The principal issues in this debate involve concepts of herbivore-vegetation interaction, natural regulation, and ecosystem stability. I argue that attempts to resolve these issues in science have not been successful. Specifically, I argue that we cannot reject the hypothesis that natural regulation is functioning to control ungulate populations. Neither can we reject the hypothesis that burgeoning ungulate populations are fluctuating within bounds that allow continued ecosystem stability. Thus, it is inappropriate to base a decision to intervene on scientific understanding. Intervention may be warranted but, at present, the basis of such a decision must be largely political.