Serge Planes

French National Centre for Scientific Research | CNRS · CRIOBE

The reproductive systems of natural populations can greatly impact their genetic diversity by preventing or encouraging inbreeding. It is therefore crucial to have a comprehensive understanding of the mating system to evaluate a population’s ability to maintain genetic diversity over time. In this study, we examine the mating system of an endangere...

Reef shark species have undergone sharp declines in recent decades, as they inhabit coastal areas, making them an easy target in fisheries (i.e., sharks are exploited globally for their fins, meat, and liver oil) and exposes them to other threats (e.g., being part of bycatch, pollution, and climate change). Reef sharks play a critical role in coral...

The exploitation of sharks and the degradation of their habitats elevate the urgency to understand the factors that influence offspring survival and ultimately shark reproductive success. We monitored and sampled blacktip reef sharks (Carcharhinus melanopterus) in nursery habitats of Moorea Island (French Polynesia), to improve knowledge on shark r...

Coral reefs are severely threatened by global and local environmental changes. However, susceptibility to perturbations and subsequent mortality varies among coral species. In this study, we tested the contribution of genetic and environmental conditions to coral’s phenotypic response in Pocillopora spp. and Porites spp. sampled together at a large...

Coral reefs are considered one of the most emblematic ecosystems in our oceans, but their existence is increasingly threatened by climate change. In this study, natural populations of two reef-building coral genera, Pocillopora spp. and Porites spp., and one hydrocoral Millepora cf. platyphylla from two different marine provinces in the Pacific Oce...

The green turtle, Chelonia mydas , is a migratory marine species with a circumglobal distribution in tropical and temperate waters. Its natal homing behavior leads to a complex genetic structure with genetically differentiated populations that breed separately and mix within the same foraging grounds. Delineating the boundaries of these populations...

With climate projections questioning the future survival of stony corals and their dominance as tropical reef builders, it is critical to understand the adaptive capacity of corals to ongoing climate change. Biological mediation of the carbonate chemistry of the coral calcifying fluid is a fundamental component for assessing the response of corals...

Tropical coral reefs are among the most affected ecosystems by climate change and face increasing loss in the coming decades. Effective conservation strategies that maximize ecosystem resilience must be informed by the accurate characterization of extant genetic diversity and population structure together with an understanding of the adaptive poten...

Endogenous viral elements (EVEs) offer insight into the evolutionary histories and hosts of contemporary viruses. This study leveraged DNA metagenomics and genomics to detect and infer the host of a non-retroviral dinoflagellate-infecting +ssRNA virus (dinoRNAV) common in coral reefs. As part of the Tara Pacific Expedition, this study surveyed 269...

Background Over the last decade, several coral genomes have been sequenced allowing a better understanding of these symbiotic organisms threatened by climate change. Scleractinian corals are reef builders and are central to coral reef ecosystems, providing habitat to a great diversity of species. Results In the frame of the Tara Pacific expedition...

Telomeres are environment-sensitive regulators of health and aging. Here,we present telomere DNA length analysis of two reef-building coral genera revealing that the long- and short-term water thermal regime is a key driver of between-colony variation across the Pacific Ocean. Notably, there are differences between the two studied genera. The telom...

Heat waves are causing declines in coral reefs globally. Coral thermal responses depend on multiple, interacting drivers, such as past thermal exposure, endosymbiont community composition, and host genotype. This makes the understanding of their relative roles in adaptive and/or plastic responses crucial for anticipating impacts of future warming....

Coral reefs are among the most diverse ecosystems on Earth. They support high biodiversity of multicellular organisms that strongly rely on associated microorganisms for health and nutrition. However, the extent of the coral reef microbiome diversity and its distribution at the oceanic basin-scale remains to be explored. Here, we systematically sam...

Health and resilience of the coral holobiont depend on diverse bacterial communities often dominated by key marine symbionts of the Endozoicomonadaceae family. The factors controlling their distribution and their functional diversity remain, however, poorly known. Here, we study the ecology of Endozoicomonadaceae at an ocean basin-scale by sampling...

The Tara Pacific expedition (2016–2018) sampled coral ecosystems around 32 islands in the Pacific Ocean and the ocean surface waters at 249 locations, resulting in the collection of nearly 58 000 samples. The expedition was designed to systematically study warm-water coral reefs and included the collection of corals, fish, plankton, and seawater sa...

The Tara Pacific program and expedition focused on coral reefs across the Pacific Ocean and used a coordinated sampling effort to address questions at multiple scales using a common suite of samples. Here, we highlight some of the Tara Pacific achievements, discussing the benefits of long-duration sea expeditions for investigating a wide array of r...

Coral reef science is a fast-growing field propelled by the need to better understand coral health and resilience to devise strategies to slow reef loss resulting from environmental stresses. Key to coral resilience are the symbiotic interactions established within a complex holobiont, i.e. the multipartite assemblages comprising the coral host org...

Sharks can incur a range of external injuries throughout their lives that originate from various sources, but some of the most notable wounds in viviparous shark neonates are at the umbilicus. Umbilical wounds typically heal within 1 to 2 months post-parturition, depending on the species, and are therefore often used as an indicator of neonatal lif...

Scientists and managers rely on indicator taxa such as coral and macroalgal cover to evaluate the effects of human disturbance on coral reefs, often assuming a universally positive relationship between local human disturbance and macroalgae. Despite evidence that macroalgae respond to local stressors in diverse ways, there have been few efforts to...

Observers of the Polynesian Shark Observatory (ORP), a citizen science network organized mainly through the Polynesian dive centers, collected an unprecedented amount of data from more than 13,916 dives spanning 43% of the islands of French Polynesia between July 8, 2011, and April 11, 2018. The objective for this type of data collection, which is...

The coexistence of ecologically and morphologically similar species is often facilitated by the partitioning of ecological niches. While subordinate species can reduce competition with dominant competitors through spatial and/or trophic segregation, empirical support from wild settings, particularly those involving large-bodied taxa in marine ecosy...

Background The green sea turtle, Chelonia mydas, is a migratory species with a strong natal homing behavior leading to a complex population structure worldwide. The species has suffered severe declines in local populations; it is therefore crucial to understand its population dynamics and genetic structure to adopt appropriate management policies....

The Mediterranean fin whale population, Balaenoptera physalus, is resident, with almost no exchanges with the Atlantic population. The entire population was estimated at 1300 or 13,300 individuals by a recent project depending on the platform used. This disparity shows the importance of long‐term monitoring with a unique protocol of survey. Capture...

Background Shark species are overfished at a global scale, as they are poached for the finning industry or are caught as bycatch. Efficient conservation measures require fine-scale spatial and temporal studies to characterize shark habitat use, infer migratory habits, analyze relatedness, and detect population genetic differentiation. Gathering the...

Designing appropriate management plans requires knowledge of both the dispersal ability and what has shaped the current distribution of the species under consideration. Here, we investigated the evolutionary history of the endangered gray reef shark (Carcharhinus amblyrhynchos) across its range by sequencing thousands of RADseq loci in 173 individu...

The movement of organisms facilitated by anthropogenic activities is a serious threat to marine diversity, especially for endemic species that may be outcompeted from non-indigenous species (NIS). In this study, we have analyzed communities inhabiting the north of the Gulf of Aqaba, Red Sea, employing environmental DNA (eDNA) metabarcoding. That gu...

With the intensification of maritime traffic, recently emerged infectious diseases have become major drivers in the decline and extinction of species. Since 2016, mass mortality events have decimated the endemic Mediterranean Sea bivalve Pinna nobilis, affecting ca. 100% of individuals. These events have largely been driven by Haplosporidium pinnae...

Coral reefs are of paramount importance in marine ecosystems, where they provide support for a large part of the biodiversity. Being quite sensitive to global changes, they are therefore the prime targets for biodiversity conservation policies. However, such conservation goals require accurate species identification, which are notoriously difficult...

Tropical coral reefs are among the worst affected ecosystems by climate change with predictions ranging between a 70-90% loss of reefs in the coming decades. Effective conservation strategies that maximize ecosystem resilience, and potential for recovery, must be informed by the accurate characterization of extant genetic diversity and population s...

Knowledge of the genetic structure and dispersal patterns for keystone and vulnerable species is essential to the establishment of conservation strategies. Since autumn 2016, the Critically Endangered Pinna nobilis bivalve has suffered mass mortality events throughout the Mediterranean Sea, causing mortality of up to 100% in affected populations. T...

Designing appropriate management plans requires knowledge of both the dispersal ability and what has shaped the current distribution of the species under consideration. Here we investigated the evolutionary history of the endangered grey reef shark ( Carcharhinus amblyrhynchos ) across its range by sequencing thousands of RAD-seq loci in 173 indivi...

Social hierarchies within groups define the distribution of resources and provide benefits that support the collective group or favor dominant members. The progression of individuals through social hierarchies is a valuable characteristic for quantifying population dynamics. On coral reefs, some clownfish maintain size-based hierarchical communitie...

Accelerative manoeuvres, such as fast-starts, are crucial for fish to avoid predation. This escape responses include fundamental survival traits for prey that experience high predation pressure. However, no previous study has assessed escape performance in neonate tropical sharks. We quantitatively evaluated vulnerability traits of neonate tropical...

For hundreds of years, the color diversity of Mollusca shells has been a topic of interest for humanity. However, the genetic control underlying color expression is still poorly understood in mollusks. The pearl oyster Pinctada margaritifera is increasingly becoming a biological model to study this process due to its ability to produce a large rang...

Morphological variation in scleractinian corals has been variously ascribed to genetic differentiation and phenotypic plasticity, with a likely influence of both factors. Experimental approaches have dominated studies of phenotypic plasticity, for example with asymmetrical colony formation resulting from exposure to experimentally imposed unidirect...

In 2019, the status of the Mediterranean fan mussel Pinna nobilis was elevated to ‘Critically Endangered’ on the IUCN Red List, in response to the pandemic caused by the parasite Haplosporidium pinnae . Identifying refuge habitats, free from parasites, is critical to the survival of the mussel. The distribution of P. nobilis was investigated along...

Coral reef science is a fast-growing field propelled by the need to better understand coral health and resilience to devise strategies to slow reef loss resulting from environmental stresses. Key to coral resilience are the symbiotic interactions established within a complex holobiont, i.e. the multipartite assemblages comprising the host coral org...

This study focuses on ocean waves impacting the Moorea Island in French Polynesia, where coral reefs play an essential role in the biodiversity and protection of habitations. We investigate how the innovative Surface Waves Investigation and Monitoring (SWIM) instrument of the Chinese‐French Oceanography SATellite satellite enables to document on a...

Background: The shanny Lipophrys pholis is an intertidal fish that is widely distributed throughout the Northeast Atlantic. Characterized by limited adult mobility and a long pelagic larval duration, the shanny stands as an ideal model to better understand larval dispersal and connectivity dynamics, which are critical parameters with implications...

The Tara Pacific expedition (2016-2018) sampled coral ecosystems around 32 islands in the Pacific Ocean and the ocean surface waters at 249 locations, resulting in the collection of nearly 58,000 samples. The expedition was designed to systematically study warm coral reefs and included the collection of corals, fish, plankton, and seawater samples...

Over the last decade, several coral genomes have been sequenced allowing a better understanding of these symbiotic organisms threatened by climate change. Scleractinian corals are reef builders and are central to these ecosystems, providing habitat and food to a great diversity of species. In the frame of the Tara Pacific expedition, we generated t...

Current climatic projections warn about the survival of tropical coral reefs and their biodiversity in the future (1). Calcifying organisms such as scleractinian corals are particularly vulnerable to ongoing ocean warming and acidification (2). Therefore, an in-depth understanding of the process of coral skeletal secretion vs environmental factors...

Chapter 12. Status and trends of coral reefs of the Caribbean region, pp. 1-25. In: Souter, D., Planes, S., Wicquart, J., Logan, M., Obura, D., & Staub, F. (Eds.) Status of Coral Reefs of the World: 2020. Global Coral Reef Monitoring Network, International Coral Reef Iniciative, Australian Institute of Marine Science, & Australian Governement.

A mass mortality event (MME) affecting the fan mussel Pinna nobilis was first detected in Spain in autumn 2016 and spread north-and eastward through the Mediterranean Sea. Various pathogens have been blamed for contributing to the MME, with emphasis in Haplosporidium pinnae, Mycobacterium sp. and Vibrio spp. In this study, samples from 762 fan muss...

Understanding dispersal patterns is a major focus for conservation biology as it influences local survival and resilience in case of local disturbance, particularly for sessile species. Dispersal can be assessed through parentage analyses by estimating family structure and self-recruitment. This study documents the family structure of a pelagic spa...

The shanny Lipophrys pholis is an intertidal fish widely distributed throughout the Northeast Atlantic. Characterized by limited adult mobility and a long pelagic larval duration, the shanny stands as an ideal model to better understand larval dispersal and connectivity dynamics, which are critical parameters implicated in marine conservation and m...

Ecosystems face both local hazards, such as over-exploitation, and global hazards, such as climate change. Since the impact of local hazards attenuates with distance from humans, local extinction risk should decrease with remoteness, making faraway areas safe havens for biodiversity. However, isolation and reduced anthropogenic disturbance may incr...

Recently, Pinna nobilis pen shells population in Mediterranean Sea has plummeted due to a Mass Mortality Event caused by an haplosporidian parasite. In consequence, this bivalve species has been included in the IUCN Red List as “Critically Endangered”. In the current scenario, several works are in progress to protect P. nobilis from extinction, bei...

Programs and initiatives aiming to protect biodiversity and ecosystems have increased over the last decades in response to their decline. Most of these are based on monitoring data to quantitatively describe trends in biodiversity and ecosystems. The estimation of such trends, at large scales, requires the integration of numerous data from multiple...

Coral microbiomes are critical to holobiont functioning, but much remains to be understood about how prevailing environment and host genotype affect microbial communities in ecosystems. Resembling human identical twin studies, we examined bacterial community differences of naturally occurring fire coral clones within and between contrasting reef ha...