Climate change poses a challenge to the conventional approach to biodiversity conservation, which relies on fixed protected areas, because the changing climate is expected to shift the distribution of suitable areas for many species. Some species will persist only if they can colonize new areas, although in some cases their dispersal abilities may be very limited. To address this problem we devised a quantitative method for identifying multiple corridors of connectivity through shifting habitat suitabilities that seeks to minimize dispersal demands first and then the area of land required. We applied the method to Proteaceae mapped on a 1-minute grid for the western part of the Cape Floristic Region of South Africa, to supplement the existing protected areas, using Worldmap software. Our goal was to represent each species in at least 35 grid cells (approximately 100 km 2 ) at all times between 2000 and 2050 despite climate change. Although it was possible to achieve the goal at reasonable cost, caution will be needed in applying our method to reserves or other conservation investments until there is further information to support or refine the climate-change models and the species' habitat-suitability and dispersal models.Planificación para el Cambio Climático: Identificación de Corredores de Dispersión Mínima para las Proteaceae del Cabo Resumen: El cambio climático representa un reto para la estrategia tradicional de la conservación de la biodiversidad que se basa enáreas protegidas fijas, porque se espera que el cambio climático cambie la distribución deáreas adecuadas para muchas especies. Algunas especies solo persistirán si pueden colonizar nuevasáreas, aunque sus aptitudes dispersoras pueden ser muy limitadas en algunos casos. Para abordar este problema ideamos un método cuantitativo para identificar múltiples corredores de conectividad en hábitats con diferentes aptitudes que primero busca minimizar las demandas de dispersión y elárea requerida después. § 1064Planning for Climate Change Williams et al.Utilizamos software Worlmap para aplicar el método a Proteaceae en un mapa con cuadrícula de un minuto de la parte occidental de la región Florística del cabo en Sudáfrica, unárea que suplementa a lasáreas protegidas existentes. Nuestra meta era representar cada especie presente en al menos 35 celdas (aproximadamente 100 km 2 ) entre 2000 y 2050 a pesar del cambio climático. Aunque era posible alcanzar la meta con un costo razonable, se requiere precaución al aplicar nuestro método en reservas u otras inversiones de conservación hasta que haya más información para sustentar o refinar los modelos de cambio climático y los modelos de aptitud del hábitat y de dispersión de especies.Palabras Clave: algoritmos para la selección deáreas, aptitud del hábitat, conectividad, conservación de la biodiversidad, modelado bioclimático, persistencia de especies

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We tabulate three measures of rarity: local abundance, breeding range size and elevational extent for the passerine birds of the New World. We determine what fraction of species is threatened with extinction within the combinations of these three measures. Species with smaller ranges, lower abundances and narrower elevational bands suffer higher levels of threat across lowland, montane and island species. For a given range size, lowland species suffer higher levels of threat than island or montane species. (This is counter to the intuition that island species -and those isolated on mountain topsmight be ecologically naïve.) When all three factors are considered together, there is only a slight tendency for lowland species to be disproportionately more threatened. Simply, island and montane species tend to be relatively common within their restricted ranges and their increased abundance reduces their likelihood of being threatened. Elevation is a consistent but relatively unimportant factor in determining threat; abundance and range size are much more important, and have an interactive effect on threatened status. We calculate the number of humans with which each species shares its breeding range, and find that this number does not aid in predicting threat status.