Changes in the potential stocks of coral reef ecosystem services following coral bleaching in Sekisei Lagoon, southern Japan: implications for the future under global warming

Abstract

Climate change is projected to have large impacts on natural capital and ecosystem services under scenarios of the IPCC. In the summer of 2016, elevated seawater temperatures triggered mass coral bleaching in Sekisei Lagoon, southern Japan. Based on data from field surveys and relevant websites, we mapped potential stocks of four major ecosystem services (fisheries production, aquarium fish production, recreational diving, and seaweed control) supplied by coral reef fishes before and after the bleaching event and predicted the possible future state of socio-ecological systems in the lagoon under climate change. We also evaluated whether current management options had mitigated the negative effects of extreme heating and coral bleaching on the potential stocks. Before the coral bleaching, the potential stock of recreational diving was estimated as 41.44 billion Japanese yen per year for the entire lagoon, while those of fisheries and aquarium fish productions were 2.10 billion and 15.03 billion yen, respectively. After bleaching, the four potential stocks including seaweed control decreased. The marine park zone and the extermination area of crown of thorns starfish mitigated changes in fish species richness and the value of recreational diving following coral bleaching. Extreme heating and coral bleaching are considered to be representative of a possible future state under global warming, and the results suggest that even management for local disturbances can mitigate the interactive effect of climate change on the potential stocks. Additional integrative management accounting for climate change and local stressors would be necessary for protecting ecosystem services in Sekisei Lagoon.