Coral reefs are considered one of the most vulnerable environments to future climate change. These threats include ocean acidification and coral bleaching. In recent decades, coral reefs have been repeatedly affected by these events, affecting even remote islands that have not been directly impacted by humans. It is therefore of utmost importance to assess whether and how corals can adapt to future climate change. However, this is complicated by the fact that coral reef systems are affected by environmental changes on different time scales, ranging from short-term disturbances to historical and geological periods that cannot be directly observed by humans. This session aims to bring together scientists from diverse backgrounds to investigate the interplay of past environmental and climatic changes on different time scales and their effects on corals and coral reefs. Contributions may include, but are not limited to, reconstructions of past environmental conditions, the application of geochemical proxies, coral growth and calcification, reef growth and decline, paleontology, and paleoecology.

Keywords: geological drivers, palaeontology, paleoecology geochemical proxies, coral growth and calcification

Session chairs: Miriam Pfeiffer, Christian-Albrechts-Universität zu Kiel (Germany), and Stéphanie Reynaud, Centre Scientifique de Monaco (Monaco)

Coral reefs are amongst the most productive and diverse ecosystems on earth. The foundation of these systems is a plethora of ecosystem functions and services provided by complex interactions of micro- and/or macroorganisms. These functions and services range from the construction of a 3-dimensional reef framework as habitat and shelter to its deconstruction, increasing structural complexity and providing calcium carbonate sands, as well as from the fixation of inorganic carbon and nitrogen as the building blocks of life to the recycling and remineralization of organic matter. This complex interplay of functions and services evolved over millennia and was shaped by varying local and regional environmental conditions to form a diversity of coral reef environments across the globe.

This session encourages contributions to the latest findings on the functioning and structure of coral reef ecosystems. The aim is to bring together studies from the organism to the ecosystem level in the fields of functional and trophic ecology, evolutionary and natural history, as well as biogeography. We also invite research from mangrove, seagrass, and deep-sea environments to foster a broad interdisciplinary exchange. Understanding the role of organisms in ecosystem functioning under past and current conditions is crucial to develop effective management interventions, to counteract the ongoing degradation of these enigmatic ecosystems and to preserve them for the future.

Keywords: evolutionary and natural histories, biogeography, trophic relationships, functional ecology, bioconstruction and bioerosion processes

Session chairs: Christine Schönberg, National Sun Yat-Sen University (Taiwan), and Benjamin Mueller, Universität Bremen (Germany)


Microorganisms play an important role in the life of plants and animals. They are involved in nutrient acquisition and recycling, disease resistance and in general health of their host. The term “holobiont” was therefore introduced to describe the biological entity comprising a eukaryotic host and its associated microorganisms, including bacteria, archaea, protists, microalgae, fungi and viruses, and their relationships to each other. Scleractinian corals are one of the best known holobionts in marine ecosystems. They are defined by the relationship between coral polyps and dinoflagellate Symbiodiniaceae algae and form the basis of light-dependent reef ecosystems. Other important habitat-forming holobionts are the Porifera – marine sponges that form complex partnerships with microbes, profoundly influencing their metabolic functions and facilitating niche expansion. However, macroalgae and other metazoans also represent ecologically functional holobiont systems in reef communities. The health and resilience of reef ecosystems depend on symbiotic interactions and homeostasis within reef holobionts. Anthropogenic stressors such as ocean acidification, pollution, overfishing and rising sea temperatures due to climate change can disrupt this delicate balance. Coral bleaching, for example, disrupts the symbioses of coral holobionts and can lead to reduced reef fitness and potential degradation.

Knowledge of the evolution, biology, and ecology of holobionts is critical to understanding the vulnerability of coral reef organisms to environmental stressors and their adaptability to new conditions. This session will focus on all aspects of holobiont biology, physiology, and ecology, covering processes at the molecular, cellular, and organismal levels. Contributions may include studies on symbiotic relationships, disease dynamics, holobiont genetics and adaptive traits, as well as bleaching and other stress responses associated with climate change. Our goal is to expand our knowledge of the mechanisms underlying the ability of reef holobionts to survive and thrive in our oceans, both in their current state and under the inevitable, rapidly changing environmental conditions.

Keywords: chemical ecology, photobiology, symbioses

Session chairs: Christine Ferrier-Pages, Centre Scientifique de Monaco (Monaco), Francesca Benzoni, King Abdullah University of Science and Technology (Saudi Arabia), and Laura Núñez Pons, Stazione Zoologica Anton Dohrn Napoli (Italy)

Session 4 – Global Climate Change and Environmental Stressors

Coral reef ecosystems, spanning from tropical to temperate latitudes, are confronting significant environmental stressors, including warming, ocean acidification, and deoxygenation. These challenges not only directly impact the metabolism and survival of reef organisms but also indirectly contribute to the emergence of diseases and alter the natural trophic structure of coral reefs. As we grapple with alarming predictions for the future, gaining a better understanding of how organisms and communities respond to environmental changes becomes increasingly crucial. Specifically, we need to explore evidence of their ability to acclimatize and potentially adapt.

Multiple approaches can aid us in this endeavour. Lab experiments under controlled conditions can discern subtle changes in organism metabolism and fitness, helping us to disentangle the combined environmental impacts on organisms and/or communities. Examining real-world examples of habitat simplification and the tropicalization of reef ecosystems provides valuable insights into the ongoing shifts that some coral reefs are experiencing. Leveraging natural laboratories, such as CO2 seeps, semi-enclosed lagoons, and mangroves, becomes pivotal for integrating responses within a more ecologically relevant context.

For this reason, in this session, we invite contributions from scientists engaged in lab-based experiments, in situ observations, and studies at natural analogues. By fostering collaboration across these diverse approaches, we aim to advance our understanding of coral reefs resilience in the face of environmental challenges.

Keywords: climate crisis effects, dynamics of coral reefs through climate change, relationships between environmental changes and coral disease, tropicalization, what we can learn from marginal and extreme reefs

Session chairs: Riccardo Rodolfo-Metalpa, Institut de Recherche pour le Développement (New Caledonia), and Ulisse Cardini, Stazione Zoologica Anton Dohrn (Italy)

Anthropogenic activities are altering the climate and ecosystems at a global scale, making it increasingly challenging for organisms to keep pace with the associated rapid ecological changes in their environment. Coral reefs are particularly affected due to the sensitivity of sessile and sedentary organisms that form the backbone of these ecosystems.  The worldwide decline of coral reef ecosystems has made it imperative to better understand the mechanisms underpinning evolutionary processes and how they influence and are influenced by demographic processes, population connectivity, interspecific interactions, and the interactions of species with their abiotic environment. These ecological processes are important in directing and constraining evolutionary processes, and in turn such evolutionary change greatly affects coral reef conservation and restoration efforts. This session aims to bridge the gap between the fields of coral reef ecology and evolution, bringing together ecologists, evolutionary biologists, physiologists, molecular biologists, and modelers to give presentations on how ecological changes associated with climate change affect our ability to conserve and restore coral reefs now and into the future. Furthermore, this session aims to not only contribute novel data, but also robust experimental designs, innovative theories and synthesis talks to drive research addressing the conservation and restoration of coral reefs in the face of climate change.

Keywords: effects of tourism, overfishing, chemical pollution, plastics and other emerging contaminants, nature-based solution to coral reef restoration, the supercoral hypothesis, coral aquaculture

Session chairs: Timothy Ravasi, Okinawa Institute of Science and Technology (Japan), and James Davis Rimer, University of the Ryukyus (Japan)

Coral reefs are one of the most species-rich and ecologically complex marine ecosystems, which provide food and livelihoods for hundreds of millions of people. However, they are facing global decline due to human-induced pressures, including overexploitation, land-use change, pollution, ocean warming and acidification. Rapid population growth and densely inhabited coastal areas increase dependence on marine resources, which, combined with exacerbating human pressures on coral reef ecosystems, threatens their conservation and the services they provide.

A more holistic management approach is advisable to address coral reef ecosystem threats and challenges. Ecosystem-based management incorporates the full range of interactions within ecosystems, moving away from traditional strategies focused on conserving individual species. It favours an integrated approach considering multiple impacts and all connections between species, ecosystem components and humans. This holistic approach aims to ensure sustainable ecosystems, thus safeguarding the goods and services they provide for future generations. However, as ecosystem-based management is applied to large and diverse areas and over large time scales, more spatial and temporal data are needed to help management make sound decisions for coral reef conservation. To bridge the gap, decision-makers and non-governmental organizations worldwide are increasing volunteers’ involvement to improve their ability to monitor and manage natural resources through citizen science projects and other participatory approaches, at the same time increasing civil society’s awareness on environmental issues and its involvement in decision-making processes. As a consequence, reliable scientific data are co-produced and can be used within the so-called quintuple innovation helix framework (academia-industry-government-civil society-environment) to address sustainable development.

This session aims to highlight actions and methods focused on ecosystem-based management and community-based monitoring of coral reefs and coral related habitats. Contributions may include, but are not limited to, studies that bridge the gap between management strategies and participatory approaches, provide new technologies that support long-term community-based monitoring, implement marine spatial planning resulting from ecosystem-based management approaches, apply nature-based solutions to habitats protection and restoration.

Keywords: marine spatial planning, stakeholder engagement, citizen science, people awareness

Session chairs: Fiona Merida, Great Barrier Reef Marine Park Authority (Australia), Daniel Wangpraseurt, Scripps Institution of Oceanography – UC San Diego (USA), Massimo Ponti, University of Bologna (Italy)

Coastal temperate reefs are highly diverse and productive ecosystems that provide critical goods and services to our societies, including nutrient cycling, food and livelihood provision, and coastal protection. The intricate networks of species interactions formed by the vast taxonomic groups of reef species and associated organisms collectively contribute to the high-diverse temperate reef biodiversity. However, these ecosystems are particularly exposed to both global environmental change, such as ocean warming and acidification, as well as local stressors, including pollution, habitat destruction, bioinvasions, and overfishing. These threats reshape the structure and functioning of coastal reefs and have major consequences on marine biodiversity, species adaptation, and resilience, compromising their ability to support human sustainability and wellbeing. Despite the key role that temperate reefs play in coastal areas and their vulnerability to global change, our understanding of these ecosystems remains limited. This session welcomes ideas from across disciplines to ask the broad question: How are today’s coastal temperate reefs shaping the reefs of the future in a changing ocean? This session aims to be highly interdisciplinary and integrative, combining work on biodiversity, community structure and dynamics, population connectivity, genetics, and ecosystem functioning to enhance the resilience of temperate reefs now and in the future. We also encourage abstracts aimed at identifying temperate reefs whose oceanographic setting provides resilience to climate change, and are therefore critical candidates for marine conservation efforts.

Keywords: biodiversity, connectivity, functioning and threats, biological invasions

Session chairs: Nuria Teixido, Stazione Zoologica di Napoli (Italy), Jeremy Carlot, Sorbonne Université & CNRS (France), and Steeve Comeau, Sorbonne Université & CNRS (France)

Mesophotic Coral Ecosystems (MCEs) are deep reef communities that occur from ~30–150 m, and have been estimated to encompass more areal reef habitat (i.e., ~60-80% global cover) than shallow reefs.  These deep reefs are typically further offshore from anthropogenic stressors (e.g., coastal development and point-source discharges) and below the depth limits of most natural stressors (e.g., storm events and thermal effects), which led to the hypothesis that MCEs could provide a refuge for many coral reef species and might potentially replenish degraded shallow reefs.  Mesophotic reefs represent a challenging frontier for direct underwater research that can be only partially explored with ROV studies. The observations and sampling performed during technical dives are unveiling unexpected aspects both regarding biodiversity and ecosystem functioning. In temperate and tropical areas, the connectivity between mesophotic-shallow and mesophotic-deep habitats is still an open debate that cannot be solved by looking for general rules. Studies focused on the controversial “refugia hypothesis” need to be discussed considering the peculiarity of each site, both from a temporal and spatial point of view. The climate crisis, even if dramatic in its effects on the marine environment, is offering a unique opportunity to test the role of the mesophotic zone in coastal benthic assemblage dynamics. While a general understanding of MCE structure and function may be impossible to develop giving apparent site-specific differences, with increasing knowledge, and depending on the considered taxa, we can likely identify patterns which future research can test globally.

This session will focus on all aspects of mesophotic reefs. Contributions may include studies on the biodiversity, ecology, and physiology of mesophotic species to highlight how the experiences coming from tropical mesophotic reefs can contaminate and inspire the research on temperate reefs, and vice-versa.

Keywords: biodiversity, connectivity, functioning and threats

Session chairs: Marc Slattery, University of Mississippi (USA), and Carlo Cerrano, Polytechnic University of Marche (Italy)

Underwater surveying through images acquired by divers and unmanned underwater vehicle has been used for many applications in oil industry, archaeology, and biology. There was a significant improvement in integrated applications using photogrammetry, acoustic surveying, laser-based methods, hyperspectral sensors. The accuracy needed for the applications changed from some cm level till high accuracy level requirement (less than 1 cm accuracy), like for multi-temporal analysis for change detection purposes, depending on the instruments and camera settings used and the distance to the imaged object. Consequently, to new instruments development, a significant evolution has been realized on methods, algorithms, datasets and their applications to underwater objects and structures 3D modelization.

We would like to invite you to submit memories even on to new methods using deep learning and machine vision to different wavelengths including hyperspectral, acoustic, and laser-based methods.

We also want to address problems related to the semantics of generated 3D models: to gather original research on application and background issues arising from the design of conceptual models, ontologies and semantic web technologies applied to coral reefs and more generally corals related habitats and species.

Keywords: precise survey, unmanned and deep surveys, image semantic segmentation, data FAIR

Session chairs: Alessandro Capra, University of Modena and Reggio Emilia (Italy), and Kimon Papadimitriou, Aristotle University of Thessaloniki (Greece)

Dive into the intricate world of coral reefs through the lens of socio-economic dynamics in our upcoming session, “Coral Reefs Under a Socio-Economic Perspective.” Embark on a captivating journey exploring the multifaceted realm of coral reefs within the context of socio-economic dynamics in our session, “Coral Reefs Under a Socio-Economic Perspective.” This session promises an illuminating discourse on the profound significance of coral reefs beyond their ecological value, focusing on their pivotal role in providing essential ecosystem goods and services crucial for human well-being.

We invite contributions that delve into the intersection of coral reef conservation and social sciences approaches. Share your insights on the intricate balance between human societies and these vibrant marine ecosystems. How can we craft effective conservation policies that safeguard these reefs while considering the socio-economic needs of local communities?

Moreover, the session will spotlight innovative ideas fostering a ‘blue circular economy,’ showcasing sustainable practices that not only preserve coral reefs but also promote economic growth and well-being. How can we create economic systems that not only benefit from but also actively contribute to the preservation of these vital natural resources?

Furthermore, the session will spotlight the imperative of evaluating the ecosystem services offered by coral reefs. Share your research, methodologies, and findings that elucidate the quantification and valuation of these invaluable services. How can a comprehensive understanding of the ecosystem services of coral reefs inform better conservation strategies and policy frameworks?

Join us in shaping a comprehensive understanding of coral reefs that transcends ecological boundaries, acknowledging their profound socio-economic significance. Share your research, perspectives, and innovative strategies to inspire a collective effort towards the sustainable preservation of these underwater wonders. Your contributions will fuel discussions that drive meaningful action, fostering a harmonious coexistence between humanity and the mesmerizing world of coral reefs. Submit your insights and be part of this transformative dialogue.

Keywords: ecosystem goods and services, social sciences approaches, conservation policies, blue circular economy, evaluation of the ecosystem services of coral reefs

Session chairs: Nathalie Hilmi, Centre Scientifique de Monaco (Monaco), and Nicolas Pascal, Blue Finance (France)

Coral reefs, as hyperdiverse ecosystems, host thousands of species fulfilling crucial ecological roles and providing essential ecosystem services. This diverse array of organisms ranges from sub-microscopic entities shaping microbial communities to micro- and macroscopic lesser-known invertebrates and algae. This session aims to shed light on the evolutionary pathways and biodiversity of often-overlooked reef taxa, expanding our comprehension beyond the more extensively studied realms of corals and fishes.

Given the unprecedented challenges facing coral reefs due to global change, understanding the complete spectrum of biodiversity within these ecosystems becomes imperative. Focusing on neglected reef taxa, this session seeks to uncover insights capable of informing conservation strategies, influencing policy formulation, and guiding future research endeavours. Contributions exploring the evolution, biodiversity and ecology of these taxa are invited, promoting a more comprehensive perspective on, and understanding of, coral reef ecosystems.

Keywords: invertebrates, algae, plants, fungi, genomics, transcriptomics, systematics, phylogeny, phylogenomics, phylogeography, connectivity, non-indigenous species, cryptic species

Session chairs: Gert Wörheide, Ludwig-Maximilians-Universität München (Germany), and Marc Kochzius, Vrije Universiteit Brussel (Belgium)

This session invites new and innovative ideas of coral reef science, from individual projects to national and multinational initiatives, that address the aims of the United Nations Decade of Ocean Science for Sustainable Development (2021-2030,

To enable the “coral reefs we want” (clean, healthy and resilient, productive, predicted, safe, accessible, inspiring and engaging) under ongoing and future climate change, next to reducing fossil fuel emissions immediately, we must complement existing approaches with transformative research, pushing new boundaries to achieve step-changes in our understanding of challenges and solutions, and increasing predictive capacity for complex systems. According to the Ocean Decade Network, it is critical to deliver on the following ten challenges: (1) understand and beat marine pollution; (2) protect and restore ecosystems and biodiversity; (3) sustainably feed the global population; (4) develop a sustainable and equitable ocean economy; (5) unlock ocean based solutions to climate change; (6) increase community resilience to ocean hazards; (7) expand the global ocean observing system; (8) create a digital representation of the ocean; (9) skills, knowledge and technology for all; (10) change humanity’s relationship with the ocean.

In this session, we are looking for new conceptual and methodological approaches and solutions at various scales in time and space that transcend disciplinary boundaries to deliver on one or more of these challenges, with a focus on coral reef science. The session aims to explore mid to long-term scientific advances, so preliminary ideas and results are encouraged.

Keywords: Mid- and long-term perspectives in science development

Session chairs: Sally Keith, Lancaster University (United Kingdom), and Thomas Felis, MARUM/University of Bremen (Germany)

Although the chosen different sessions are general and wide-ranging, the fields of research around coral reefs are difficult to summarize in a limited number of topics. Therefore, this session wants to open the doors to the most innovative, diverse and/or cross-cutting studies, which cannot be fully identified with the previous sessions.

Session chairs and committee members: This session will be moderated by the ECRS24 Scientific Committee: Massimo Ponti, Carlo Cerrano, Gert Wörheide, Michael Sweet, Benjamin Müller, Laura Núñez Pons, Caterina Longo, Monica Montefalcone, Riccardo Rodolfo-Metalpa, Christine Ferrier-Pages