Identifying management opportunities to combat climate, land, and marine threats across less climate exposed coral reefs.

Conserving coral reefs is critical for maintaining marine biodiversity, protecting coastlines, and supporting livelihoods in many coastal communities. Climate change threatens coral reefs globally, but researchers have identified a portfolio coral reefs (bioclimatic units, BCUs) that are relatively less exposed to climate impacts and connected to other reef systems. These reefs provide a proactive opportunity to secure a long-term future for coral reefs under climate change. To help guide local management efforts, we quantified cumulative human impacts (CHI) from climate, marine and land pressures (2013 and between 2008-2013) within BCUs and across countries tasked with BCU management. Additionally, we created a management index based on common management measures and policies for each pressure source (climate, marine, land) to identify a country's potential intent and/or commitment to effectively manage these pressures and to guide local management efforts within these BCUs. We found that 22 countries (79%) experienced increases in CHI between 2008 and 2013. Climate change pressures had the highest proportional contribution to CHI across all reefs and in all but one country (Singapore), but eighteen BCUs (35%) and nine countries containing BCUs (32%) had relatively high land and marine impacts. There was a significant positive relationship between climate impact and the climate management index across countries, potentially signifying those countries experiencing greater climate impacts are more committed to managing them. However, this trend was driven by climate management intent in Fiji and Bangladesh. Our results can be used to guide future fine-scale analyses, national policies and local management decisions, and our management indices reveal areas where management components can be improved. Cost-effectively managing local pressures (e.g., fishing, nutrients) within BCUs is essential for building a climate ready future that benefits both coral reefs and people. This article is protected by copyright. All rights reserved.