Meta‐analysis of Red List conservation assessments of Mexican endemic and near endemic tree species shows nearly two thirds of these are threatened

Abstract

Mexico's extraordinary tree diversity is threatened by the increasing demand for resources because of the tenfold population growth in the last century. The conservation status of trees and both urban and rural livelihoods are also negatively affected by agriculture, mining and tourism. Nearly 60% of the Mexican endemic and near endemic tree species whose conservation status we have assessed for the Red List of the International Union for Conservation of Nature are threatened, almost double the percentage of threatened trees worldwide. If no measures are taken to protect this tree diversity properly, these resources will be forever lost for human sustainability. Summary• Mexico is floristically the fourth most species-rich country in the world. Currently, 3620 native tree species are reported from this country. Mexico has been a forerunner at global level in recognising the need for plant conservation, yet this is in stark contrast with governmental programmes and actions, past and present that negatively affect(ed) immense areas of primary vegetation. In the framework of the Global Tree Assessment, to date, we have assessed the conservation status of nearly 1500 Mexican endemic and near endemic tree species for the International Union for the Conservation of Nature (IUCN) Red List, the distribution data of which we use here for a first meta-analysis of conservation statuses and spatial distribution patterns in a newly delimited area we call Natural Mexico.• Our database consists of 112,416 taxonomically and geographically very carefully curated distribution points of 1474 tree species endemic to Mexico and adjacent areas, belonging to 98 flowering plant families. The extensive curation methodology we consider essential for both research and conservation purposes is emphasised.

The Global Tree Assessment provides a multifaceted view on the future of tree diversity conservation

“…Generally, many countries with 1000 plant species or fewer fall below the global trend. Most countries with higher than average threat levels compared with the global trend are island nations, such as Sri Lanka, Cuba, the Philippines, and Indonesia, except for Mexico, which Samain et al (2022) discuss in their paper. The relationship between the proportions of endemic species versus threatened species is considerably more scattered, with island nations generally containing higher proportions of endemic species.…”

“…In Papua New Guinea, where 36% of species are threatened, a significant proportion of species are also data deficient (Barstow et al, 2022). In Mexico, the assessment excludes plant groups for which no monograph exists, resulting in the exclusion of a considerable amount of the overall plant diversity (Samain et al, 2022). Moreover, the most diverse floras often have a higher proportion of rare species.…”

“…Data were adopted from the State of the World's Trees Supplementary Table 1 (BGCI, 2021). excludes plant groups for which no monograph exists, resulting in the exclusion of a considerable amount of the overall plant diversity (Samain et al, 2022). Moreover, the most diverse floras often have a higher proportion of rare species.…”