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

We identified 2375 potential climate adaptation corridors, 1573 of which occurred primar- ily within our 7 focal countries (Table 1). The total number of corridors per country ranged from 64 in El Salvador to 485 in Mexico, despite only considering a fraction of Mexico in our analysis. Median corridor length ranged from 81 km (Costa Rica) to 358 km (Belize) and was 165 km across all countries (Table 1 and Fig 3A). The shortest corridor originating in each country ranged from 6 km (within Cerro Azul National Park, Honduras) to 185 km (Deep River Forest Reserve, Belize to Cusuco National Park, Honduras, crossing through Guate- mala). Median corridor elevational breadth ranged from 1720 m (Panama) to 2183 m (Belize) and was 1867 m across all countries (Table 1 and Fig 3B). A total of 1312 corridors (55%) were within a single country, whereas 784 (33%), 197 (8%), and 82 (3%) corridors spanned 2, 3, and 4 countries, respectively. Corridors in Belize typically spanned the most countries (median = 3 countries), whereas in contrast, corridors in Colombia, Costa Rica, Honduras, and Panama typically were the most self-contained (median = 1 country) (Table 1). Overall, potential cli- mate adaptation corridors were distributed throughout the region and varied widely in terms of length, elevational breadth, and countries spanned. Climate adaptation corridor protection and ecological characteristics The protection and ecological characteristics of potential climate adaptation corridors were highly variable across the region. Corridors in Panama were most protected (median = 64%),

followed by Belize (median = 49%), and Honduras (median = 47%) (Table 1 and Fig 3C). Cor- ridors located in El Salvador were the least protected (median = 10%). Of the 36 fully protected corridors, Panama and Honduras had the most fully protected corridors (16 and 8, respec- tively), whereas Colombia, Costa Rica, and Mexico all had 3–5 fully protected corridors and 5 were shared between Panama and Colombia. Corridors located in Belize overlapped with the most protected areas (median = 19), with medians of 3–7 overlapping protected areas per cor- ridor across all other countries (Table 1 and Fig 3D). Similarly, corridors located in Belize also overlapped with the most KBAs (median = 6), with medians of 2–3 overlapping KBAs for all other countries (except partial Colombia with a median of 1 KBA) (Table 1 and Fig 3E). Corri- dors in Belize were generally the longest (median = 358 km) (Fig 3A), which may explain the larger number of overlapping protected areas and KBAs. Both number of overlapping Table 1. Summary statistics for potential climate adaptation corridors by country*. Country Corridors Length (km) Elevation range (m) Protection (%) Overlapping protected areas Overlapping KBAs Countries crossed Forest biomass (Mt C) Belize 194 185, 358, 860 1674, 2183, 2480 30, 49, 66 9, 19, 27 4, 6, 11 2, 3, 4 56, 65, 72 Colombia^ 317 14, 134, 805 1241, 1797, 3553 1, 19, 100 1, 3, 15 0, 1, 5 1, 1, 2 30 67, 117 Costa Rica 317 11, 81, 291 1400, 1978, 3440 4, 36, 100 1, 4, 11 1, 3, 7 1, 1, 2 34, 65, 97

El Salvador 64 30, 104, 200 1542, 1922, 2343 2, 10, 44 1, 4, 19 0, 2, 5 1, 2, 3 26, 39, 68 Guatemala 340 17, 159, 451 1527, 2020, 3942 1, 36, 100 1, 7, 20 0, 3, 8 1, 2, 3 17, 60, 83 Honduras 251 6, 141, 532 1310, 2033, 2685 6, 47, 100 1, 4, 24 0, 2, 10 1, 1, 3 24, 58, 81 Mexico^ 485 21, 276, 1158 1279, 1866, 2528 1, 35, 100 1, 5, 28 0, 3, 13 1, 2, 4 26, 58, 79 Nicaragua 145 104, 247, 510 1249, 1736, 2696 5, 29, 86 2, 6, 13 0, 3, 8 1, 2, 2 31, 52, 83 Panama 262 15, 172, 401 1296, 1720, 3392 5, 64, 100 1, 5, 14 1, 3, 9 1, 1, 2 33, 74, 100 * in columns 3–9, first, second, and third numbers are minimum, median and maximum values, respectively ^ Values are not for the entire country; our study area only included portions of southeastern Mexico and northwestern Colombia https://doi.org/10.1371/journal.pone.0304756.t001 PLOS ONE Mapping climate adaptation corridors for biodiversity PLOS ONE | https://doi.org/10.1371/journal.pone.0304756 May 31, 2024 8 / 19