No abstract

Aside from their associated direct ecological advantages, coral reef conservation programs may also generate benefits to local communities. These communities may choose to support marine conservation programs based on multiple factors, and an increased involvement of local people often leads to positive changes in environmental behaviours. This study collected qualitative data using semi-structured interviews and multi-stakeholder focus groups on a rural fisher community in Tianyar Village, North Bali, Indonesia, where the ‘North Bali Reef Conservation’ (locally known as ‘Yowana Bhakti Segara’) coral reef conservation program was based. Results showed that generally, the community of Tianyar village was in support of the existing coral reef conservation programs, mostly due to the perceived economic prospects associated with being involved in the conservation work. Overall, the community agreed that the coral reef conservation program has led to societal and environmental benefits, which has generated positive environmental behaviours and a change in mindsets since it was established in 2017 (4 years before this study was undertaken). Based on the answers of interviewees, this study makes recommendations on how coral reef conservation in Bali (and other similar less developed nations) can increase community support, socio-economic benefits and positive environmental behaviours. These include (1) continuing environmental education for within the community, (2) strengthening regulations and improving enforcement, (3) increasing financial and logistical support for waste management and ecotourism, (4) continuing building and deploying artificial reefs, ensuring that ‘best practice’ recommendations are followed, and (5) utilising the influence of local leaders to create positive environmental behaviours.

Total ocean carbon exceeds 40,000 GT either dissolved in the water column or buried in ocean sediments, and the ocean continues to sequester carbon from the atmosphere. Selective removal of predatory fish through extractive fishing alters the community structure of the ocean. This altered community results in increased biomass of more productive, low trophic level fish, higher overall fish respiration rates and lower carbon sequestration rates from fish, despite possible decreases in total fish biomass. High-pressure fishing on high trophic level fish, a globally occurring phenomenon, may result in as much as a 19% increase in respiration from fish communities overall. This increase in respiration will reduce sequestration rates and could prove highly significant in global carbon budgets. Preliminary estimates suggest a loss of sequestration equating to around 90Mt C.year−1 (~ 10% of total ocean sequestration or ~ 1% of anthropogenic fossil fuel emissions per year). Ultimately, to reduce these carbon emissions, fishing needs to be carbon optimised, alongside other fisheries management outcomes, which may mean that fewer higher trophic level fish are removed. This study highlights the potential magnitude of fishing on ocean carbon dynamics and presents the key uncertainties (including understanding the effects of fishing on zoo- and phytoplankton communities) we need to urgently research to accurately quantify the effects and model future fishing practices. Graphical Abstract

The ocean is a net sequester of carbon dioxide, predominantly through low biomass, high productivity phytoplankton photosynthesis. Selective removal of predatory fish through extractive fishing alters the community structure of the ocean, with an increased biomass of more productive, low trophic level fish and higher overall respiration rates, despite possible decreases in total fish biomass. High pressure fishing on predators may result in as much as a 19% increase in respiration from fish communities and could prove highly significant in global carbon budgets.