A Comparison of Geographic Membership Patterns in Three National Environmental Organizations

Abstract

In this county-level study, geographic patterns of membership in three national environmental organizations–World Wildlife Fund, The Nature Conservancy, and Natural Resources Defense Council–were compared to determine if similar membership patterns exist for different types of environmental organizations. Results of the study, which included correlation analysis and maps displaying location quotients, demonstrated that there were strong similarities in spatial patterns of membership among the groups. All three organizations had membership ratios that were higher than the national average in the Northeast, West, and Rocky Mountain states and lower in the Midwest and South. A ranking of location quotients by county revealed that 6 of the 10 counties with the highest member-to-population ratios were identical for the 3 groups, suggesting that there may be core locations of environmental interest within the United States. In addition to highlighting similarities in the spatial patterns of membership in diverse national environmental organizations, the study may serve as a model for environmental organizations interested in identifying geographic concentrations of their membership.