Delgado, G. L.; van den Hoogen, J.; Dent, D. H.; Bradfer Lawrence, T.; Werden, L. K.; Cole, R. J.; Diaz Quesada, C.; Jimenez Fajardo, J. A.; Mendez Rodriguez, A.; Mesen Solorzano, E.; Navarrete Chacon, G.; Coto, M.; Suarez Perez, I.; Vahlas, L.; Liang, Y.; Crowther, T. W.

Costa Rica implemented the world\'s first national-scale Payment for Ecosystem Service (PES) program in 1996 and now protects over 200,000 hectares. By distributing wealth towards local land-stewards, Costa Rica\'s program has helped to limit deforestation at a national scale, but the large-scale ecological implications have yet remained unclear. Here, we use a massive ecoacoustic dataset to evaluate how this program has impacted the ecological integrity of PES forests across the entire Nicoya Peninsula. At the times and frequencies that are indicative of native biological activity, we reveal dramatic increases in the integrity of PES soundscapes, relative to those of natural protected areas. Specifically, natural regeneration sites were 97.79% more acoustically similar to reference forests (absolute mean similarity of 0.539) than they were to disturbed pastures, while acoustic recovery of plantations lags behind (79.66%: 0.489). These findings are strongly suggestive of large-scale ecological recovery, constituting some of the most robust evidence to date that restoration initiatives can benefit biodiversity on large spatial scales.