Coral reefs worldwide are degrading due to climate change, overfishing, pollution, coastal development, coral bleaching, and diseases. In areas where the natural recovery of an ecosystem is negligible or protection through management interventions insufficient, active restoration becomes critical. The Reef Futures symposium in 2018 brought together over 400 reef restoration experts, businesses, and civil organizations, and galvanized them to save coral reefs through restoration or identify alternative solutions. The symposium highlighted that solutions and discoveries from long-term and ongoing coral reef restoration projects in Spanish-speaking countries in the Caribbean and Eastern Tropical Pacific were not well known internationally. Therefore, a meeting of scientists and practitioners working in these locations was held to compile the data on the extent of coral reef restoration efforts, advances and challenges. Here, we present unpublished data from 12 coral reef restoration case studies from five Latin American countries, describe their motivations and techniques used, and provide estimates on total annual project cost per unit area of reef intervened, spatial extent as well as project duration. We found that most projects used direct transplantation, the coral gardening method, micro-fragmentation or larval propagation, and aimed to optimize or scale-up restoration approaches (51%) or provide alternative, sustainable

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39Coral reefs worldwide are degrading due to climate change, overfishing, pollution, coastal 40 development, bleaching and diseases. In areas where natural recovery is negligible or protection 41 through management interventions insufficient, active restoration becomes critical. The Reef Futures 42 symposium in 2018 brought together over 400 reef restoration experts, businesses, and civil 43 organizations, and galvanized them to save coral reefs through restoration or identify alternative 44 solutions. The symposium highlighted that solutions and discoveries from long-term and ongoing coral 45 reef restoration projects in Spanish-speaking countries in the Caribbean and Eastern Tropical Pacific 46were not well known internationally. Therefore, a meeting of scientists and practitioners working in 47 these locations was held to compile the data on the extent of coral reef restoration efforts, advances 48 and challenges. Here, we present unpublished data from 12 coral reef restoration case studies from 49five Latin American countries, describe their motivations and techniques used, and provide estimates 50 on total annual project cost per unit area of reef intervened, spatial extent as well as project duration. 51We found that most projects used direct transplantation, the coral gardening method, micro-52 fragmentation or larval propagation, and aimed to optimize or scale-up restoration approaches (51%) 53 or provide alternative, sustainable livelihood opportunities (15%) followed by promoting coral reef 54 conservation stewardship and re-establishing a self-sustaining, functioning reef ecosystem (both 55 13%). Reasons for restoring coral reefs were mainly biotic and experimental (both 42%), followed by 56 idealistic and pragmatic motivations (both 8%). The median annual total cost from all projects was 57 $93,000 USD (range: $10,000 USD -$331,802 USD) (2018 dollars) and intervened a median spatial 58 area of 1 ha (range: 0.06 ha -8.39 ha). The median project duration was 3 years; however, projects 59 have lasted up to 17 years. Project feasibility was high with a median of 0.7 (range: 0.5 -0.8). This 60 study closes the knowledge gap between academia and practitioners and overcomes the language 61 barrier by providing the first comprehensive compilation of data from ongoing coral reef restoration 62