The IUCN Red List is widely used to guide conservation policy and practice. However, in most cases the evaluation of a species using IUCN Red List criteria takes into account only the global status of the species. Although subpopulations may be assessed using the IUCN categories and criteria, this rarely occurs, either because it is difficult to identify subpopulations or because of the effort involved. Using the jaguar Panthera onca as a model we illustrate that wide-ranging species that are assigned a particular category of threat based on the IUCN Red List criteria may display considerable heterogeneity within individual taxa in terms of the level of risk they face. Using the information available on the conservation status of the species, we evaluated the jaguar's current geographical range and its subpopulations. We identified the most threatened subpopulations, using the extent of occurrence, area of occupancy, population size and the level of threat to each subpopulation. The main outcome of this analysis was that although a large subpopulation persists in Amazonia, virtually all others are threatened because of their small size, isolation, deficient protection and the high human population density. Based on this approach, future conservation efforts can be prioritized for the most threatened subpopulations. Based on our findings we recommend that for future Red List assessments assessors consider the value of undertaking assessments at the subpopulation level. For the jaguar, sub-global assessments should be included on the Red List as a matter of urgency.

Costa Rica has one of the greatest percentages (26%) of protected land in the world. The National Protected Areas System (NPAS) of Costa Rica was established in 1976 and currently includes >190 protected areas within seven different protection categories. The effectiveness of the NPAS to represent species, populations, and areas with high species richness has not been properly evaluated. Such evaluations are fundamental to understand what is necessary to strengthen the NPAS and better protect biodiversity. We present a novel assessment of NPAS effectiveness in protecting mammal species. We compiled the geographical ranges of all terrestrial Costa Rican mammals then determined species lists for all protected areas and the estimated proportion of each species’ geographic range protected. We also classified mammal species according to their conservation status using the IUCN Red List of Threatened Species. We found almost complete representation of mammal species (98.5%) in protected areas, but low relative coverage (28.3% on average) of their geographic ranges in Costa Rica and 25% of the species were classified as underprotected according to a priori representation targets. Interestingly, many species-rich areas are not protected, and at least 43% of cells covering the entire country are not included in protected areas. Though protected areas in Costa Rica represent species richness well, strategic planning for future protected areas to improve species complementarity and range protection is necessary. Our results can help to define sites where new protected areas can have a greater impact on mammal conservation, both in terms of species richness and range protection.