Mapping climate adaptation corridors for biodiversity—A regional-scale case study in Central America

Introduction Biological corridors refer broadly to landscape features that facilitate habitat connectivity for biodiversity, particularly across fragmented landscapes often used for agriculture [1]. Growing scientific evidence demonstrates the important role of biological corridors in climate adapta- tion by facilitating species range shifts [2–5]. Hence, an emerging conservation strategy is to create “climate adaptation corridors’’ that allow species to access suitable habitat at mid to high latitudes and elevations, often by linking protected areas [6–8]. The basis of this strategy has arisen from a body of science related to paleogeography, paleoecology, and past, present, and future climate and species distribution modeling [9–11]). Mountainous, complex land- scapes are often the subject of climate adaptation corridor research owing to their environ- mental heterogeneity, topographic and vegetative buffering capacity, and relative climatic stability that together can support ecologically diverse climate change refugia that allow species to survive and adapt under changing climatic conditions [12–15]. Globally, however, protected area connectivity is generally lacking [16, 17] and over 62% of tropical forests are already incapable of facilitating range shifts to analogous future climates [18]. Whilst there has been an increase to 7.84% of global protected area connectivity [19], this still falls short of Target 3 of the Kunming-Montreal Global Biodiversity Framework to protect

and connect 30% of terrestrial, inland water, marine, and coastal areas by 2030 [20]. Therefore, considerable improvements in protected area connectivity from local to regional scales, likely via help from climate adaptation corridors, are necessary to promote biodiversity persistence under climate change. Whereas global and pan-tropical assessments are useful for international policymaking and tracking of global conservation targets, such assessments are often too coarse to inform conser- vation policy and decision making at local to national scales. This is particularly the case for smaller countries, which may be highly biodiverse but easily overlooked in global assessments and policy forums. For example, Central America consists of several relatively small countries located within the Mesoamerican biodiversity hotspot, but has a history of deforestation (often for agriculture) and varying conservation policies among countries [21]. Currently, no Central American countries meet the 30% by 2030 protected area coverage and connectivity target, particularly in terms of connectivity [22] (S1 Table in S1 Appendix), even though connectivity has been a major conservation priority in previous decades. Central American countries recognized the importance of connectivity for biodiversity with the adoption of the Mesoamerican Biological Corridor (MBC) in 1997, which originally sought to connect habitats from Mexico to Panama using the jaguar (Panthera onca), the region’s largest carnivore, as a flagship and umbrella species as the basis for this approach [23].

Although the MBC was initially lauded for its ambitious international framework and success- fully raised hundreds of millions of dollars, the envisioned regional corridor network was never truly realized due to a combination of factors including lack of coordination among countries, unclear guidelines for what constitutes a corridor, inconsistent or limited corridor monitoring criteria and data, insufficient buy-in among diverse stakeholders, and shifting pri- orities toward pursuing co-benefits between biodiversity and sustainable development [23– 25]. Consequently, individual countries have largely operated on their own terms outside the original, regional framework with variable results. In the Mexican states of Chiapas and Tabasco, corridors were initially designed to become part of the MBC using ecological criteria, but ultimately were implemented in locations acceptable to local landowners and their effec- tiveness at facilitating ecological connectivity remains unknown [26]. El Salvador developed a National Biological Corridor management strategy, but corridors have largely remained an ambiguous concept and have rarely translated from planning to practice [25]. Otherwise, there PLOS ONE Mapping climate adaptation corridors for biodiversity PLOS ONE | https://doi.org/10.1371/journal.pone.0304756 May 31, 2024 2 / 19 Central America climate adaptation corridor analysis [Data set]. In Mapping climate adaptation corridors for biodiversity - A regional-scale case study in Central America (1.0). Zenodo. https://doi. org/10.5281/zenodo.11150568.

Funding: This research was supported by the International Conservation Fund of Canada, the Bobolink Foundation, the BAND Foundation, and the Gordon and Betty Moore Foundation. BAND Foundation: https://bandfdn.org/ Bobolink Foundation: https://www.bobolinkfoundation.org/ International Conservation Fund of Canada: grant #2021-63; https://icfcanada.org/ Gordon and Betty Moore Foundation: grant #9075; https://www. moore.org/ All of these were gifts to Friends of the Osa (Osa Conservation) rather than to individual authors of this study. The BAND Foundation and Bobolink Foundation are small, family-run organizations that do not issue grant numbers per se. Sponsors or funders played no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing interests: The authors have declared that no competing interests exist.