Range-restricted species are poor proxies for functional diversity in the world's largest avifauna

Abstract

Conservation prioritization is critical in an era of global change and mass extinction, but it is complicated by the multiple facets of biodiversity that are often uncorrelated in space, especially at global scales. Yet, global scales are not the level pertinent to most conservation action; rather, conservation decision making is generally made at the country level, and this is particularly important for the most biodiverse countries on earth. Here, we evaluate congruence between three metrics of functional diversity and four metrics of taxonomic richness for the birds of Colombia, the country with the most bird species in the world. We report a high correlation between species and functional richness, and with threatened richness. However, the distribution of endemic and range-restricted species was a poor proxy for functional richness. Thus, for biodiverse countries such as Colombia, prioritizing species richness would be a suitable approach to conserving functional diversity, but it must be complemented with traditional conservation goals of preserving uniqueness (endemism) to avoid jeopardizing range-restricted species of high socio-ecological value.