Actions to scale up and implement larval propagation in reef restoration

One of the goals of the Coral Restoration Consortium (CRC) is to scale up coral restoration to ecologically meaningful scales by fostering collaboration and knowledge transfer among members and stakeholders. To accomplish this, several working groups were formed to address specific priorities within the various disciplines of coral reef restoration. One of these working groups, the larval (LP) propagation group, aims to improve methods to sexually propagate many millions of coral larvae for larger-scale coral restoration and research. The biggest challenge being addressed by the larval propagation group is to increase post-settlement survival of reef-settled and outplanted coral settlers to increase the effectiveness of this approach. Additional objectives include 1) Developing a coordinated breeding program to highlight best practices to successfully collect gametes, rear and settle coral larvae, and outplant sexual recruits; 2) Broadening the number of species targeted for restoration; 3) Expanding the number of locations that conduct larval propagation work globally; and 4) Developing new technologies to enable mass rearing and settlement of coral larvae as well as efficient outplanting to increase the cost-effectiveness of this approach. To help achieve these goals, a Caribbean Coral Spawning Database was created by members of the LP group, incorporating standardized spawning observations for as many coral species and locations as possible. The information compiled is used to generate accurate coral spawning prediction calendars, and to expand our knowledge about species-specific reproductive traits, which can then be used to develop coral breeding reference sheets. These breeding reference sheets include all information available on individual species’ reproductive biology and early life history as well as tailored best practices for larval propagation. Building on the members’ varied areas of expertise, the larval propagation group recently published a review article in Restoration Ecology highlighting best practices, knowledge gaps and priority actions for the application of coral breeding and restoration. The larval propagation membership is now expanding into Indo-Pacific and other reef regions, with the aim to create a global network of researchers, practitioners and stakeholders to increase the scales of mass larval production, settlement and recruitment of resilient corals on damaged reefs. Overall, the LP group aims to guide the coral restoration community toward actions that yield significant advances in larval rearing and coral breeding, foster collaborations, and ultimately achieve larger-scale and sustainable ecological restoration of corals and reefs.