How effective are conservation areas to preserve biodiversity in Mexico?

Abstract

Most conservation of biological diversity is achieved via networks of protected areas, including national parks, wilderness areas, and nature reserves. Protected areas are chosen predominantly for their vertebrates and vegetation, and typically it is assumed that other biota elements will be represented and managed appropriately. However, measures that are successful at conserving vertebrates or plants do not neccesary guarantee that highly-diverse taxa (e.g. insects) will be adequately maintained. Despite Mexico includes a large proportion of the biodiversity Mesoamerican hotspot, well-documented examples of insect diversity and distributions remain limited, and in many cases, sampling efforts have been biased towards ‘handy’ locations, thus limiting the role and importance of priority areas for conservation. We evaluated the coherence between conservation areas, the distribution, and diversity of a highly diverse Neotropical insect group: Erebidae moths. We considered two large spatiotemporal scales in Mexico (national and regional) to examine the consistency between the distribution of conservation polygons and moth diversity. We focused on patterns of moth diversity, endemism, spatiotemporal biases, and sampling effort. Moth species richness and sampling records are disproportionately distributed towards southern locations of Mexico (i.e., Neotropical region), but despite so, many species are only known from single records. 16% of Erebidae species are endemic to Mexico, and around 20% of these species occur in one single state (Chiapas). Intriguingly, 66% of endemic species have not been reported from protected areas in Mexico, and a similar proportion has been observed for the Chiapan region, where sampling was significantly biased towards a few Protected Natural Areas (PNAs) and vegetation types.The assessment of insect diversity in Mexico is still far from being complete since managers continue to assume that conservation areas effectively protect a whole range of species. However, we detected that sampling biases follow a spatiotemporal trend, and it represents an important obstacle to offer a complete picture of the true richness of diverse moth faunas within conservation polygons. It is not enough to have many conservation areas or to protect a minimum proportion of land if we are not able to describe their diversity and representativeness. Conservation biologists should also consider taking actions involving policymakers and society to go beyond the global decline discourse and avoid turning it into a trite topic.