Aim: Climate change and deforestation will redistribute the biodiversity in the next century. Species-specific differences in the response to such stressors will lead to distribution decoupling of interacting species, yet consequences for ecosystem services are poorly known. Here, we assess the potential effects of future niche mismatch on a key ecosystem service mediated by seed dispersal and pollination interactions in the Amazon: the sustainable exploitation of Brazil nuts.

Location: The Amazon. Major taxa studied: Woody plant, medium-sized mammals, and insects.

Time period: Present day, end of the 21st Century.

Methods: Combining ecological niche models to simulations of tree cover loss and dispersal constraints, we compare the forecasted distribution of the plant to that of its interacting fauna of pollinators and seed dispersers.

Results: Our projections indicate that climate change itself could have no or slightly negative effects on the distribution of the Brazil nut tree, expected to increase by 6% by year 2090. However, range contractions of nearly half of all the suitable climate for pollinators may lead up to 80% reduction on co-occurrence potential. In addition, local pollinator richness is expected to reduce by 20%, with likely consequences for pollination redundancy and resilience to subsequent environment changes. Although reductions on the suitable area of some seed dispersers were also forecasted in the future, potential co-occurrence with the plant and local species richness were mostly unabated in most of our projections.

Main conclusion: The forecasted declines in pollinator diversity may hamper ecosystem function redundancy and threaten the long-term resilience of the services provided by Brazil nut trees. Such pervasive and indirect effects of climate change, often neglected and unaccounted for in most conservation assessments, may cascade into economies and human well-being worldwide.