Global patterns of terrestrial vertebrate diversity and conservation

Abstract

Identifying priority areas for biodiversity is essential for directing conservation resources. Fundamentally, we must know where individual species live, which ones are vulnerable, where human actions threaten them, and their levels of protection. As conservation knowledge and threats change, we must reevaluate priorities. We mapped priority areas for vertebrates using newly updated data on >21,000 species of mammals, amphibians, and birds. For each taxon, we identified centers of richness for all species, small-ranged species, and threatened species listed with the International Union for the Conservation of Nature. Importantly, all analyses were at a spatial grain of 10 × 10 km, 100 times finer than previous assessments. This fine scale is a significant methodological improvement, because it brings mapping to scales comparable with regional decisions on where to place protected areas. We also mapped recent species discoveries, because they suggest where as-yet-unknown species might be living. To assess the protection of the priority areas, we calculated the percentage of priority areas within protected areas using the latest data from the World Database of Protected Areas, providing a snapshot of how well the planet's protected area system encompasses vertebrate biodiversity. Although the priority areas do have more protection than the global average, the level of protection still is insufficient given the importance of these areas for preventing vertebrate extinctions. We also found substantial differences between our identified vertebrate priorities and the leading map of global conservation priorities, the biodiversity hotspots. Our findings suggest a need to reassess the global allocation of conservation resources to reflect today's improved knowledge of biodiversity and conservation.

Keywords: biogeography; conservation planning; endemism; species distributions.

Fig. 1.

Global maps of species richness for different categories of species. The top row shows the richness of all species in the taxon. For birds, we used breeding ranges only. The middle row shows the richness of threatened species (vulnerable, endangered, or critically endangered in the IUCN Red List). The bottom row shows the richness of species whose geographic ranges are smaller than the median range size for that taxon. Maps use a 10 × 10 km grid and the Eckert IV equal-area projection.

Fig. 2.

Overlap of global species richness centers. Richness centers include cells that are among the globally richest 5% for at least one of the taxa. (A) All species, (B) IUCN listed threatened species, (C) Small-ranged species.

Fig. 3.

Comparison of diversity centers for small-ranged vertebrates with the 25 original Myers biodiversity hotspots (4) and the 34 hotspots from Hotspots Revisited (22).

Fig. 4.

Selected priority ecoregions based on small-ranged vertebrates.

Fig. 5.

Species discoveries since 1950. Maps show only species having range maps.