Conservation status, rarity, and geographic priorities for conservation of Chilean mammals: an assessment

摘要

To assign priorities for the conservation of Chilean Non-volant Terrestrial Mammals (NTM) we developed a Conservation Priority Index (CPI). The analysis based on the CPI shows that 49 out of 82 species or 60% of Chilean NTM are of priority for conservation. These species are usually specialized in habitat requirements, a low percentage of their habitats are within the National System of Protected Areas, and have restricted geographic distributions. Out of these 49 species, 16 can be considered Fragile, and 33 as threatened (19 Vulnerable, 11 Endangered. and three Critical species). The level of threat of Chilean mammals, as assessed by CPI scores, was found to be affected by taxonomic affiliation, diet, and body mass. A complementary analysis, based on species rarity, points out the existence of 34 species of Chilean NTM with narrow geographic range and low average population density. Rarity status was not affected by food habits, but was affected by taxonomic affiliation. Carnivores were significantly rarer than rodents. The simultaneous application of the CPI and rarity analyses allowed us to identify seven species that are rare according to our analysis but do not have a CPI value high enough to be included in some of the categories discussed above. We propose to group these species under the category Indeterminate. The analysis at the level of Chilean ecoregions shows that total species richness is correlated with the number of rare and threatened species per ecoregion, but no relationship was detected between total species richness per ecoregion and the number of endemic species at the level of the country, This suggests that a strategy for conserving species-rich areas most of the time will also protect a large proportion of rare and threatened species, although this would not provide protection for Chilean endemic species. The Matorral ecoregion, of which only 0.5% of its total area is currently protected, contains a large proportion of endemic species, hence its importance for conservation. A geographic strategy to protect Chilean NTM may have to consider the Matorral ecoregion as a priority along with the Puna, and Patagonian Steppe. In these latter two ecoregions is where most diversity is concentrated and where the largest number of rare and threatened species is found.