Scale misperceptions and the spatial dynamics of a social–ecological system

Abstract

The interactions between an ecosystem and thehuman rules for the use of that system can be verycomplex. This complexity means that it is hard todesign foolproof and sensible rules. Here we ex-plore a particular set of difficult questions: Whatare the consequences of misunderstanding or mis-perceiving the spatial structure of populations wewish to exploit? What if the ‘scale’ of naturalpopulations and their interactions do not matchthe scale of our decisions? For example, what ifwe think we are managing a single large popula-tion, when in fact there are multiple, small, spa-tially discrete populations?These are important and relevant questions. Inthe 1950s and 1960s many environmental pro-grams were initiated at the national or interna-tional level. As a consequence, both the theoryand practice of environmental and resource man-agement have focused on a scale of authorityappropriate to national and international regula-tory bodies. In fisheries, for example, the firstserious attempts at management began with theinternational organizations for the northwest andnortheast Atlantic and the whale and the tunacommissions. With the advent of extendedfisheries jurisdiction (i.e. the 200-mile limit), na-tional organizations took over much of the au-thority of the international bodies, but oftenretained intact the same theory and the same scaleof regulation (generally over large areas involvingthousands of square kilometers). Of necessity, reg-ulatory bodies operating at this scale are forced toignore the fine-scale aspects of the systems theyregulate.The poor performance of regulated oceanfisheries provides ample reason to question thescale of regulatory attention. A number of recentpapers (Sinclair, 1988; Hutchins and Meyers,1995; Ames, 1996; Wroblewski et al., 1996;Wilson et al., 1998) have focused attention on theexistence of populations at a smaller scale thanthat usually managed by national or internationalregulatory authorities. The usual thrust of these