Coral reef restoration is a rapidly growing movement galvanized by the accelerating degradation of the world's tropical coral reefs. The need for concerted and collaborative action focused on the recovery of coral reef ecosystems coalesced in the creation of the Coral Restoration Consortium (CRC) in 2017. In March 2020, the CRC leadership team met for a biennial review of international coral reef restoration efforts and a discussion of perceived knowledge and implementation bottlenecks that may impair scalability and efficacy. Herein we present six priorities wherein the CRC will foster scientific advancement and collaboration to: (1) increase restoration efficiency, focusing on scale and cost‐effectiveness of deployment; (2) scale up larval‐based coral restoration efforts, emphasizing recruit health, growth, and survival; (3) ensure restoration of threatened coral species proceeds within a population‐genetics management context; (4) support a holistic approach to coral reef ecosystem restoration; (5) develop and promote the use of standardized terms and metrics for coral reef restoration; and (6) support coral reef restoration practitioners working in diverse geographic locations. These priorities are not exhaustive nor do we imply that accomplishing these tasks alone will be sufficient to restore coral reefs globally; rather these are topics where we feel the CRC community of practice can make timely and significant contributions to facilitate the growth of coral reef restoration as a practical conservation strategy. The goal for these collective actions is to provide tangible, local‐scale advancements in reef condition that offset declines resulting from local and global stressors including climate change.

Coral reefs are subject to numerous physical disturbances, and post-disturbance coral recovery potential depends on subsequent re-colonization of impacted habitat. We examined divergent recovery trajectories at 2 proximal reefs disturbed by ship groundings that resulted in clearly delineated areas of altered substrate. Post-disturbance measurements of coral recruitment, survival, and changes in community structure were made approximately annually from 2009−2013 in undisturbed reference areas as well as disturbed pavement and rubble areas. Despite similar initial physical disturbances, there were marked differences between sites, with higher coral recruitment and survival on disturbed pavement than rubble bottom, reference reef, or restoration structures. Subsequent episodic disturbances from rubble mobilization could be a mechanism driving the divergent recovery patterns. To estimate whether local hydrodynamic conditions were sufficient to mobilize rubble, we used a combination of long-term monitoring, hydrodynamic modeling, and rubble transport mechanics to hindcast the potential for substrate mobility. Long-term model simulations of hydrodynamic forcing at the study sites showed multiple events where bottom-orbital velocities exceeded thresholds required to mobilize rubble via sliding or overturning. Our analyses indicate that wave energy mobilizes rubble substrate multiple times annually and suggests a physical limitation on survival of coral recruits relative to those on pavement substrate. Continued mobilizations may establish a positive feedback loop in which continued rubble clast mobilizations cause additional mechanical erosion or breakage and a shift to smaller rubble sizes that would subsequently mobilize at a lower level of hydrodynamic forcing and thus become subject to more frequent and sustained disturbances. The combination of multiple hydrodynamic disturbances and unstable substrate limits coral recovery and thus contributes to prolonged habitat loss.

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Ocean warming is increasing the incidence, scale, and severity of global-scale coral bleaching and mortality, culminating in the third global coral bleaching event that occurred during record marine heatwaves of 2014-2017. While local effects of these events have been widely reported, the global implications remain unknown. Analysis of 15,066 reef surveys during 2014-2017 revealed that 80% of surveyed reefs experienced significant coral bleaching and 35% experienced significant coral mortality. The global extent of significant coral bleaching and mortality was assessed by extrapolating results from reef surveys using comprehensive remote-sensing data of regional heat stress. This model predicted that 51% of the world’s coral reefs suffered significant bleaching and 15% significant mortality, surpassing damage from any prior global bleaching event. These observations demonstrate that global warming’s widespread damage to coral reefs is accelerating and underscores the threat anthropogenic climate change poses for the irreversible transformation of these essential ecosystems.