Optimising the effectiveness of Coralclip® to secure corals back to the reef has required new understanding of the biology of attachment – the process by which corals naturally re-cement themselves to reef substates. We are using new approaches to define how attachment effectiveness varies across coral species and reef environment.
Maintaining or improving coral cover and diversity rests on understanding rates of natural recovery. We assess coral recruitment on the reef to understand the scale and extent with which outplanting should be conducted to benefit the reef beyond that which is possibly naturally. We also examine how growing corals in our nurseries can be used to generate colonies that are sexually mature and therefore contribute to natural recruitment.
An important aspect of using coral propagation to improve reef resilience to future stress is ensuring replanted coral communities are stress tolerant. We have been applying novel molecular screening tools to identify different genetic variants of key coral species, and then subjecting these genotypes to high-throughput heat stress assays to identify which are most stress tolerant. This in turn informs choice of coral for propagation and outplanting.
Corals associate with a variety of microbes (including symbiotic algae and bacteria) that are fundamental to health – this can be either positively by providing essential nutrients, or negatively by acting as pathogens. We examine how growing and out-planting coral across diverse environments impacts their “microbiome” and in turn healthy functioning.
Nursery-based coral propagation is an essential activity within the Coral Nurture Program, to ensure we grow diverse coral species (and genotypes) – we track how well these corals grow across diverse reef environments to ensure nurseries are placed in the best locations. We examine how our nurseries support local fish communities (for example where herbivorous fish naturally nursery structures) and also fast-track corals to the size at which they can begin to sexually reproduce.
A critical element of the Coral Nurture Program’s success has been accelerating the rate, scale and cost-effectiveness of re-planting coral – however, it is not about how many we plant but about how many of these ultimately survive. We evaluate how outplant survivorship is affected by reef environment for different coral species, to guide what best to plant and where (and so optimise “success”).
Community structure of the many organisms that live on a coral reef are dependent on the abundance and diversity of corals present. Since the beginning of the Coral Nurture Program, we have been documenting how intensive outplanting influences the trajectory of reef ecology recovery, in comparison to neighbouring “control” reef sites. We conduct parallel experiments tracking how planting specific coral species influences success of reef recovery.
Coral propagation “success”, is commonly measured in general metrics of growth and survivorship. We have been developing new “multi-trait” measurement approaches to target deeper understanding of how coral biology is affected by intensive propagation. As part of this work, we have been developing new tools to identify functionally different coral colonies, in real time, to maximise how we choose diverse stock for nursery propagation.
Tracking industry benefits – including economic rationale – of coral propagation is a critical feature as to when and where activity should be initiated, continued or stopped. We closely track social and economic impacts throughout our program life cycle to ensure that our research-informed efforts are continually tailored to optimise cost-effectiveness and return on investment.
At Coral Nurture Program we know collaboration is key for securing a future for the world’s coral reefs. We actively collaborate with other scientists and practitioners around the world to share learnings and address unique scientific questions. We encourage people to get in touch with any collaboration proposals that align with our research themes.
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