Large wild herbivores slow down the rapid decline of plant diversity in a tropical forest biodiversity hotspot

1. The UN declaration of the Decade of Ecosystem Restoration 2021-2030 emphasizes the need for effective measures to restore ecosystems and safeguard biodiversity. Large herbivores regulate many ecosystem processes and functions, yet their potential as a nature-based solution to buffer against long-term temporal declines in biodiversity associated to global change and restore diversity in secondary forests remains unknown.

2. By means of an exclusion experiment, we tested experimentally the buffering effects of large wild herbivores to avert against long-term biodiversity collapse in old-growth and secondary tropical forests in the Atlantic Forest of Brazil where sapling abundance and species richness declined circa 20% over the course of 10 years. The experiment comprised 50 large herbivore exclosure-open control plot pairs (25 at the old-growth forest and 25 at the secondary forest), where 2m2 were monitored in every plot during a 10-year period.

3. Large herbivores were able to...