Sensitivity of Systematic Reserve Selection to Decisions about Scale, Biological Data, and Targets: Case Study from Southern British Columbia

Abstract

The identification of conservation areas based on systematic reserve-selection algorithms requires decisions related to both spatial and ecological scale. These decisions may affect the distribution and number of sites considered priorities for conservation within a region. We explored the sensitivity of systematic reserve selection by altering values of three essential variables. We used a 1:20,000-scale terrestrial ecosystem map and habitat suitability data for 29 threatened vertebrate species in the Okanagan region of British Columbia, Canada. To these data we applied a reserve-selection algorithm to select conservation sites while altering selection unit size and shape, features of biodiversity (i.e., vertebrate species), and area conservation targets for each biodiversity feature. The spatial similarity, or percentage overlap, of selected sets of conservation sites identified (1) with different selection units was ≤40%, (2) with different biodiversity features was 59%, and (3) with different conservation targets was ≥94%. Because any selected set of sites is only one of many possible sets, we also compared the conservation value (irreplaceability) of all sites in the region for each variation of the data. The correlations of irreplaceability were weak for different selection units (0.23 ≤ r ≤ 0.67), strong for different biodiversity features (r = 0.84), and mixed for different conservation targets (r = 0.16; 0.16; 1.00). Because of the low congruence of selected sites and weak correlations of irreplaceability for different selection units, recommendations from studies that have been applied at only one spatial scale must be considered cautiously.Resumen: La identificación deáreas de conservación basada en algoritmos de selección sistemática de reservas requiere decisiones relacionadas tanto con la escala espacial como la ecológica. Estas decisiones pueden afectar la distribución y el número de sitios considerados prioridades de conservación en una región. Exploramos la sensibilidad de la selección sistemática de reservas alterando los valores de tres variables esenciales. Utilizamos un mapa de ecosistema terrestre a escala 1:20,000 y datos de aptitud de hábitat para 29 especies amenazadas de vertebrados en la región de Okanagan en Columbia Británica, Canadá. Aplicamos un algoritmo de selección sistemática de reservas a estos datos para seleccionar sitios de conservación mientras se alteraba el tamaño y la forma de la unidad seleccionada, las características de la biodiversidad (es decir, especies de vertebrados) y los objetivos de conservación para cada característica de biodiversidad del paisaje. La similitud espacial, o porcentaje de traslapamiento, de conjuntos de sitios de conservación selectos identificada 656 Sensitivity of Systematic SelectionWarman et al. con (1) diferentes unidades de selección fue ≤40%, (2) diferentes características de biodiversidad fue 59% y (3) diferentes objetivos de conservación fue ≥94%. Debido a que cualquier conjunto de sitios seleccionado es solo uno de muchos conjuntos po...

Conservation planning in a subdivided world

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