Drivers of urban biodiversity in Mexico and joint risks from future urban expansion, climate change, and urban heat island effect

governments, civil organizations, and academia in each municipality should work together to elaborate on conservation plans and define local actions to improve the effectiveness of these urban conservation areas (e.g., reducing urban heat island effects). For instance, these elements can help us identify the shape, size, and location of additional protected areas for targeted taxa and reinforce the effectiveness of urban green corridors for dispersal [13]. Such knowledge would be helpful in guiding strategies to decide how to expand urban areas, integrating explic- itly nature’s contributions to people (NCP) to alleviate the problem of urban heat islands. Accordingly, some specific activities should be implemented quickly to reduce biodiversity loss and heat stress. For instance, removing feral and stray dogs and cats should be a priority for local Mexican authorities in the next years due to the well-known impacts of these species on urban wildlife and people’s health [84]. Further, implementing extensive tree plantation programs and creating extensive green spaces in low-income neighborhoods across Mexican municipalities (particularly those in higher risk; Fig 3) is key for adapting to the ongoing regional-local climate change impacts. These kinds of local actions are win-win strategies with multiple benefits simultaneously because they reduce heat stress on the human population and increase local urban biodiversity. Besides, we need to remember that urban areas represent only 1.0% of the terrestrial surface of our planet [85], but the indirect impacts go well beyond

that share. In Mexico, urban areas account for ~1.2% [86], but the influence of cities on biodi- versity is not limited to these crowded areas. Further studies are necessary to assess the effects of urban externalities on rural areas. Conclusions Our results suggest that urban planning in Mexico should explicitly consider the need to implement mitigation and conservation actions. Mexican municipalities with less than five species were variable for each taxonomic group (Table C in S1 Data). Additional surveys in these municipalities will be necessary to establish whether this low number of species is not a sampling artifact. The rarefaction analysis gave us a comprehensive dataset of urban biodiver- sity for a large set of Mexican municipalities (389). We call for further studies with local sur- veys at finer scales to understand better the ecological and evolutionary processes shaping urban biodiversity in Mexico. Some conservation actions might be implemented quickly to improve habitat diversity (e.g., restoration or conservation planning) and prioritize those municipalities with small urban areas and low species richness. As urbanization sprawls towards the periphery of towns, where remnant vegetation tends to exist, it will be necessary to consider those sites as potential protected areas and study the possibility of connecting them through green corridors of native vegetation. Such urban green spaces need restoration and expansion to mitigate UHI’s impacts (and additional risks such as air quality, noise pollution, etc.), habitat fragmentation, and cli-

mate change. Besides, data on species and populations should increase and improve through long-term monitoring to evaluate the importance of protected areas and green spaces in cities for different species and higher taxa. Finally, Mexican urban planners should interact more with conservation biologists, social scientists, and climate change experts to help design and restructure cities in Mexico. Integrating disciplines would be crucial to alleviate biodiversity loss as urbanization and climate change processes occur. Supporting information S1 Appendix. Supplementary figures. (PDF) PLOS ONE Urban biodiversity and anthropogenic pressures PLOS ONE | https://doi.org/10.1371/journal.pone.0308522 October 4, 2024 14 / 19