Gilles Lepoint

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Verified

Gilles verified their affiliation via an institutional email.

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• PhD
• Senior Researcher at University of Liège

The damselfishes, with more than 340 species, constitute one of the most important families that live in the coral reef environment. Most of our knowledge of reef-fish ecology is based on this family, but their trophic ecology is poorly understood. The aim of the present study was to determine the trophic niches of 13 sympatric species of damselfis...

1. Stable isotope analysis, coupled with dietary data from the literature, was used to investigate trophic patterns of freshwater fauna in a tropical stream food web (Guadeloupe, French West Indies). 2. Primary producers (biofilm, algae and plant detritus of terrestrial origin) showed distinct δ13C signatures, which allowed for a powerful discrimin...

Dead leaves of the Neptune grass, Posidonia oceanica (L.) Delile, in the Mediterranean coastal zone, are colonized by an abundant " detritivorous " invertebrate community that is heavily predated by fishes. This community was sampled in August 2011, November 2011, and March 2012 at two different sites in the Calvi Bay (Corsica). Ingested artificial...

In recent years, sea ice cover along coasts of East Antarctica has tended to increase. To understand ecological implications of these environmental changes, we studied benthic food web structure on the coasts of Adélie Land during an event of unusually high sea ice cover (i.e. two successive austral summers without seasonal breakup). We used integr...

Deadwood stores about 8% of global carbon stock, and its decomposition is a key factor in forest ecosystems. Deadwood‐associated (saproxylic) organisms constitute a food web that sustains a substantial part of biodiversity globally. After fungi, saproxylic beetles are the most prominent agents of structural deadwood decomposition in forests. They a...

This study investigates essential (Mg, Ca, Fe, Mn, Cu, Zn, Se, Ni) and non-essential (Li, Be, Cr, Rb, Sr, Cs, Cd, Sn, Ba, and Pb) element concentrations and stable isotope (δ13C, δ15N, δ34S) compositions in feathers of Brown Boobies (Sula leucogaster) from three distinct Atlantic islands: the Archipelagos of Saint Peter and Saint Paul (SPSP), Abrol...

Given the cryptic and elusive nature of prey consumption, quantifying its contribution to the diet of free-ranging primates using behavioral methods is challenging. In this context, the use of carbon and nitrogen-stable isotopes represents a promising alternative approach. Here, we used stable isotope analysis to estimate the proportion of arthropo...

Fatty acid (FA) composition is a useful information for investigating trophic ecology of marine organisms and how they interact within food webs. In Antarctica, the diversity and availability of food sources depends on the ice cycle and disturbances. Benthic organisms receive variable quantities of sinking sea ice algae or phytoplankton. Benthic pr...

We report estimates of community gross primary production (GPP), community respiration (CR), and net community production (NCP) based on the change of dissolved O2 during incubations over epilithic turf-forming macroalgae (Halopteris scoparia, Padina pavonica, and Dictyota dichotoma) on 7 occasions and in accumulations of Posidonia oceanica macroph...

Climate change and resource exploitation in the Southern Ocean are important Anthropogenic pressure on Antarctic food webs. Understanding the eco-functional roles of Antarctic communities is essential for ecosystem management and conservation. Amphipods are among the most dominant and ecologically important benthic taxa in the Southern Ocean. The a...

We present the first open-access, island-wide isotopic database (IsoMad) for modern biologically relevant materials collected on Madagascar within the past 150 years from both terrestrial and nearshore marine environments. Isotopic research on the island has increasingly helped with biological studies of endemic organisms, including evaluating fora...

This study investigates the essential (Mg, Ca, Fe, Mn, Cu, Zn, Se, Ni) and non-essential (Li, Be, Cr, Rb, Sr, Cs, Cd, Sn, Ba, and Pb) element concentrations and stable isotope (δ 13 C, δ 15 N, δ 34 S) compositions in the feathers of Brown Boobies (Sula leucogaster) from three distinct Brazilian islands: the Archipelagos of Saint Peter and Saint Pau...

In a global context of invasive alien species (IAS), native predators are often eradicated by functionally different IAS, which may induce complex cascading consequences on ecosystem functioning because of the key role predators play in structuring communities and stabilizing food webs. In permanent ponds, the most abundant freshwater systems on Ea...

The benthic compartment of the Southern Ocean is highly constrained by sea ice spatio-temporal dynamics. Along the West Antarctic Peninsula (WAP), sea ice dynamic is changing in response to climate change. This results in a longer ice-free period, an increase of light availability, and changes in primary producers supporting benthic organisms. Over...

Crinoids of the Order Comatulida are renowned for harboring a remarkable diversity of symbiotic organisms within echinoderms, including polychaetes, myzostomids, gastropods, crustaceans, brittle stars, or fish. Crinoids provide essential services to their symbionts, such as shelter, access to food resources, mating areas, nesting grounds, and nurse...

The functioning of Mediterranean coastal waters is deeply affected not only by global environmental changes (e.g., global warming, climate change) but also by improvements in sewage treatment as required by the European Water Framework Directive. These changes affect nutrient concentrations and cycling, and primary production. The present paper pre...

Chemical pollution is a global concern as contaminants are transported and reach even the remote regions of Antarctica. Seabirds serve as important sentinels of pollution due to their high trophic position and wide distribution. This study examines the influence of migration and trophic ecology on the exposure of two Antarctic seabirds, Wilson's st...

Coloration change is a common phenomenon in the marine environment, particularly for organisms that are cryptic or use passive/active camouflage (e.g. cephalopods). When two organisms are symbiotically associated, they may harbor similar colors that improve their survival by decreasing their predation rate. However, when the symbiont is separated f...

This study investigated total mercury (THg) concentrations in feathers and eggs of resident and migratory Antarctic seabirds. Stable isotope data (δ15N, δ13C, and δ34S) were employed to ascertain the key factors influencing the exposure of these species to Hg. We gathered feathers and eggs from three resident species - Adélie, Gentoo, and Chinstrap...

Seaweed farming for the production of carrageenan is a growing economic activity. Like everywhere in the marine environment, farmed algae such as Kappaphycus alvarezii can host algal organisms as epiphytes. Epiphytes ensure important functions in natural ecosystems, but these organisms can have negative impacts on their hosts and, in aquaculture be...

This study investigated total mercury (THg) concentrations in feathers and eggs of resident and migratory Antarctic seabirds. Stable isotope data (δ15N, δ13C, and δ34S) were employed to ascertain the key factors influencing the exposure of these species to Hg. We gathered feathers and eggs from three resident species - Adélie, Gentoo, and Chinstrap...

Mercury (Hg) and stable carbon and nitrogen isotope ratios were analysed in body feathers from nestlings of white-tailed eagles (Haliaeetus albicilla) (WTE; n = 13) and Northern goshawks (Accipiter gentilis) (NG; n = 8) and in red blood cells (RBC) from NG (n = 11) from Norway. According to linear mixed model, species factor was significant in expl...

Alien predator introduction is a global threat to amphibians. Yet, there is a lack of in situ studies of trophic interactions between alien predators and native amphibians, particularly concerning small predatory fish such as mosquitofish. Mosquitofish originate from the United States but have been introduced globally, including intentionally for m...

The environmental variability of Northern Chilean Patagonia during the last millennia is evaluated using a multi-proxy analysis of sediment cores from Lake Esponja (45°S 72°W) to decipher if the sediment deposition is controlled by volcanic eruptions, landslides induced by earthquake or heavy rainfall. The lake is located in a glacio-tectonic valle...

The levels of eighteen trace elements (TEs) were evaluated in association with stable isotopes (δ15N, δ34S, and δ13C) in feathers and eggs of five migratory species breeding on the Antarctic Peninsula to test the factors that influence their exposure to contaminants. The feathers of seabirds migrating to the Northern Hemisphere (South polar skua) h...

Among the most common contaminants in marine ecosystems, trace elements are recognized as serious pollutants. In Corsica (NW Mediterranean Sea), near the old asbestos mine at Canari, trace elements from the leaching of mine residues have been discharged into the sea for several decades. The aim of this study was to assess the levels of contaminatio...

In Mediterranean, Posidonia oceanica develops a belowground complex structure ('matte') able to store large amounts of carbon over thousands of years. The inventory of blue carbon stocks requires the coupling of mapping techniques and in situ sediment sampling to assess the size and the variability of these stocks. This study aims to quantify the o...

Kelp forests dominated by Macrocystis pyrifera are widely distributed in coastal waters from boreal, temperate and subantarctic regions. This widespread distribution may result in regional differences in food web structure and functioning. In temperate northern regions, where most studies on kelp forest benthic food webs have been conducted, kelp g...

In this study, we investigated factors that influence the differences in exposure of perfluoroalkyl acids (PFAAs) from eight species of Antarctic seabirds, including Pygoscelis penguins, Stercorarius maccormicki, and Macronectes giganteus. We analyzed the relationship between foraging ecology (based on δ13C, δ15N, and δ34S values) and PFAAs accumul...

Despite the role that goatfishes play in reef ecosystems, knowledge of their ecomorphological diversity remains scarce. Here, we explore the ecomorphology of six species of goatfishes living in sympatry at Toliara Reef (South-West of Madagascar) by using a combination of morphometric and isotopic (δ¹³C, δ¹⁵N and δ³⁴S) data. The shape of cephalic re...

Seagrass, systems export significant amounts of their primary production as large detritus (i.e. macrophytodetritus). Accumulations of exported macrophytodetritus (AEM) are found in many areas in coastal environment. Dead seagrass leaves are often a dominant component of these accumulations, offering shelter and/or food to numerous organisms. AEM a...

Termites feed on vegetal matter at various stages of decomposition. Lineages of wood- and soil-feeding termites are distributed across terrestrial ecosystems located between 45°N and 45°S of latitude, a distribution they acquired through many transoceanic dispersal events. While wood-feeding termites often live in the wood on which they feed and ar...

To date, only one mitogenome from an Antarctic amphipod has been published. Here, novel complete mitochondrial genomes (mitogenomes) of two morphospecies are assembled, namely, Charcotia amundseni and Eusirus giganteus. For the latter species, we have assembled two mitogenomes from different genetic clades of this species. The lengths of Eusirus an...

The iterative nature of ecomorphological diversification is observed in various groups of animals. However, studies explicitly testing the consistency of morphological variation across and within species are scarce. Antarctic notothenioids represent a textbook example of adaptive radiation in marine fishes. Within Nototheniidae, the endemic Antarct...

Coastal hypoxia is a worldwide concern. Even though seasonal hypoxia has been reported on the northwestern Black Sea shelf since the 1970s, little is known about oxygenation in this area over the Holocene. With a multiproxy approach, this work aimed to detect potential hypoxic events in two gravity cores. Our results demonstrate that the most commo...

Sea stars (Echinodermata: Asteroidea) are a key component of Southern Ocean benthos, with 16% of the known sea star species living there. In temperate marine environments, sea stars commonly play an important role in food webs, acting as keystone species. However, trophic ecology and functional role of Southern Ocean sea stars are still poorly know...

Deep-sea elasmobranchs are commonly reported as bycatch of deep-sea fisheries and their subsequent loss has been highlighted as a long-running concern to the ecosystem ecological functioning. To understand the possible consequences of their removal, information on basic ecological traits, such as diet and foraging strategies, is needed. Such aspect...

In this study, we evaluated the suitability of body feathers, preen oil and plasma for estimation of organohalogen compound (OHC) exposure in northern goshawk Accipiter gentilis nestlings (n = 37; 14 nests). In addition, body feathers received further examination concerning their potential to provide an integrated assessment of (1) OHC exposure, (2...

Migratory bird species may serve as vectors of contaminants to Antarctica through the local deposition of guano, egg abandonment, or mortality. To further investigate this chemical input pathway, we examined the contaminant burdens and profiles of the migratory South polar skua (Catharacta maccormicki) and compared them to the endemic Adélie pengui...

In order to test the feasibility of transplantation of the whip black coral species Cirrhipathes anguina (Dana, 1846) from Madagascar, transplants were installed on cultivation tables in two sites (the North Pass and the Grande Vasque) characterized by distinct environmental conditions. Following transplantation, the transplants were followed for s...

Antarctic sea stars can occupy different trophic niches and display different trophic levels, but, while the impacts of their body size and environmental features on their trophic niches are potentially important, they are presently understudied. Here we assessed the trophic ecology in relation to the size and habitat of sea stars in a fjord on Kin...

Native fauna of the tropical volcanic part of Guadeloupe is amphidromous: juveniles born in rivers but that grow in the sea need to migrate upstream to colonise their adult habitat in rivers. This migration is affected by any human-made obstacles placed in their way. Moreover, on volcanic tropical islands, streams are the main source of water catch...

The West Antarctic Peninsula (WAP) is one of the most rapidly changing regions in the world, in great part due to anthropogenic climate change. Steep environmental gradients in water temperature, sea ice cover and glacier melting influence are observed, but much is left to document about significance of those shifts for biological communities and e...

Mercury (Hg) concentrations have significantly increased in oceans during the last century. This element accumulates in marine fauna and can reach toxic levels. Seafood consumption is the main pathway of methyl-mercury (MeHg) toxicity in humans. Here, we analyzed total Hg (T-Hg) concentrations in two oceanic squid species (Ommastrephes bartramii an...

Contaminant levels are lower in Antarctica than elsewhere in the world because of its low anthropogenic activities. However, the northern region of the Antarctic Peninsula, is close to South America and experiences the greatest anthropogenic pressure in Antarctica. Here, we investigated, in two Antarctic Peninsula islands, intra and interspecific f...

Salinity resistance of the African rice species (Oryza glaberrima) is poorly documented and the specific responses of the plant to Na⁺ and Cl⁻ toxic ions remain unknown. Cultivars TOG5307 and TOG5949 were maintained for 15 days on iso-osmotic nutrient solutions containing 50 mM NaCl, or a combination of Cl⁻ salts (Cl⁻-dominant) or Na⁺ salts (Na⁺-do...

Paleolimnological reconstructions from the mid and high latitudes in the Southern Hemisphere are still relatively scarce. Anthropogenic impacts have evidenced trophic state changes and an increase in cyanobacterial blooms in the lacustrine system of San Pedro de la Paz in the last decades. Here, we reconstructed primary production and sedimentologi...

Accumulation of exported macrophytodetritus (AEM) represent unique habitats formed by the dead material originating from macrophyte ecosystems (e.g., seagrass, kelp, other seaweeds). AEM can be found everywhere, from the littoral zone to the deepest canyons, and from high to low latitudes. Seagrass AEMs are among the most common detrital accumulati...

Paedomorphosis, a developmental heterochrony involving the retention of larval traits at the adult stage, is considered a major evolutionary process because it can generate phenotypic variation without requiring genetic modifications. Two main processes underlie paedomorphosis: neoteny, a slowdown of somatic development, and progenesis, a precociou...

DeepIso is a collaborative effort to produce a global compilation of stable isotope ratios and elemental contents in organisms from deep-sea ecosystems. In doing so, it aims to provide the deep-sea community with an open data analysis tool that can be used in the context of future ecological research, and to help deep-sea researchers to use stable...

In the North Sea, sympatric grey and harbour seals may compete for food resources impacted by intense fishing activities and a recent increase of seal populations. In order to reduce inter-specific competition, sympatric species must segregate at least one aspect of their ecological niches: temporal, spatial or resource segregation. Using isotopes...

The biomagnification of per- and polyfluoroalkyl substances (PFASs) was investigated in a tropical mangrove food web from an estuary in Bahia, Brazil. Samples of 44 organisms (21 taxa), along with biofilm, leaves, sediment and suspended particulate matter were analyzed. Sum (∑) PFAS concentrations in biota samples were dominated by perfluorooctane...

In Morocco, Zostera marina Linnaeus has disappeared from many localities where it was historically reported. The only known remaining meadows along Mediterranean coasts of Morocco, though in North Africa, are those of Belyounech bay and Oued El Mersa bay, in the marine area of 'Jbel Moussa'. An in-depth knowledge of these meadows is required for th...

A previous investigation of our research team has demonstrated the suitability of using hepatic total tin (ΣSn) concentrations for evaluating dolphin exposure to organotins (OTs). The present study develops the previous technique into three different approaches that comprise data: (1) on hepatic ΣSn concentrations of 121 Guiana dolphins (Sotalia gu...

A large part of the production of Laminaria hyperborea kelp forests is not directly consumed by grazers, but is exported during storm events or natural annual blade erosion. Drifting kelp fragments are transported and can accumulate temporarily over subtidal benthic habitats. The decay process is particularly slow (>6 mo for complete decay during s...

In Morocco, Zostera marina Linnaeus has disappeared from many localities where it was historically reported. The only known remaining meadows along Mediterranean coasts of Morocco, though in North Africa, are those of Belyounech bay and Oued El Mersa bay, in the marine area of ‘Jbel Moussa’. An in-depth knowledge of these meadows is required for th...

Understanding the spatiotemporal patterns of legacy organochlorines (OCs) is often difficult because monitoring practices differ among studies, fragmented study periods, and unaccounted confounding by ecological variables. We therefore reconstructed long-term (1939–2015) and large-scale (West Greenland, Norway, and central Sweden) trends of major l...

Posidonia oceanica is the only reported seagrass to produce significant amount of dimethylsulfoniopropionate (DMSP). It is also the largest known producer of DMSP among coastal and inter-tidal higher plants. Here, we studied (i) the weekly to seasonal variability and the depth variability of DMSP and its related compound dimethylsulfoxide (DMSO) in...

Damselfishes of the genus Stegastes are among the most conspicuous benthic reef associated fish in the Gulf of California, and the two most commonly found species are the Beaubrummel Gregory Stegastes flavilatus and the Cortez damselfish Stegastes rectifraenum. Both species are described as ecologically and morphologically very similar. However, th...

Termites are eusocial insects having evolved several feeding, nesting and reproductive strategies. Among them, inquiline termites live in a nest built by other termite species: some of them do not forage outside the nest, but feed on food stored by the host or on the nest material itself. In this study, we characterized some dimensions of the ecolo...

Shallow-water antipatharians host many symbiotic species, which spend their adult life with their host and/or use them to have access to food. Here we determine the trophic relationships between four common macrosymbionts observed on/in Cirripathes anguina, Cirrhipathes densiflora and Stichopathes maldivensis in SW Madagascar. These include the myz...

We reconstructed the first long-term (1968–2015) spatiotemporal trends of perfluoroalkyl substances (PFAS) using archived body feathers of white-tailed eagles (Haliaeetus albicilla) from the West Greenland (n = 31), Norwegian (n = 66), and Central Swedish Baltic coasts (n = 50). We observed significant temporal trends of perfluorooctane sulfonamide...

Rationale: Stable isotope analysis is used to investigate the trophic ecology of organisms and, in order to use samples from archived collections, and it is important to know whether preservation methods alter the results. This study investigates the long-term effects of four preservation methods on sea stars isotopic composition and isotopic nich...

Among the fauna inhabiting the Posidonia oceanica seagrass meadow, holothurians are particularly abundant and provide essential ecological roles, including organic matter recycling within seagrass sediments. This study aimed to investigate the trophic niche of four holothurians of the order Holothuriida [Holothuria poli (Delle Chiaje, 1824), Holoth...

The pigments are present in all photosynthetic organisms, mainly as light-gathering agents for photosynthesis and photo-protection (Porra et al., 1997), namely chlorophylls (Chls), carotenoids, photoprotective compounds and their derivatives. These are commonly stored in the sediments of lacustrine environments and are produced by algae, phototroph...

La paleolimnología es definida como el estudio de las condiciones físicas, químicas y biológicas a través de la información almacenada en los depósitos sedimentarios de lagos. En la mayoría de los casos, los sedimentos lacustres también contienen importantes datos indirectos de cambios ambientales pasados como en el periodo del Quaternario tardìo ....

The black caiman is one of the largest neotropical top predators, which means that it could play a structuring role within swamp ecosystems. However, because of the difficulties inherent to studying black caimans, data are sorely lacking on many aspects of their general biology, natural history, and ecology, especially in French Guiana. We conducte...

In the Kerguelen Islands, the multiple effects of climate change are expected to impact coastal marine habitats. Species distribution models (SDM) can represent a convenient tool to predict the biogeographic response of species to climate change but biotic interactions are not considered in these models. Nevertheless, new species interactions can e...

The spatiotemporal trends of mercury (Hg) are crucial for the understanding of this ubiquitous and toxic contaminant. However, uncertainties often arise from comparison among studies using different species, analytical and statistical methods. The long-term temporal trends of Hg exposure were reconstructed for a key sentinel species, the white-tail...

The whitemouth croaker (Micropogonias furnieri) is one of the most commercially important species along the Atlantic coast of South America. Moreover, some of its biological traits (long life span, inshore feeding, high trophic position) make this species a suitable sentinel of coastal pollution. Here, we investigated contamination by multiple lega...

Documenting phenotypic variation among populations is crucial for our understanding of micro-evolutionary processes. To date, the quantification of trophic and morphological variation among populations of coral reef fish at multiple geographical scales remains limited. This study aimed to quantify diet and body shape variation among four population...

The most recent eruption of Mt. Fuji (Japan), the VEI 5 Hōei plinian eruption (CE 1707) heavily impacted Lake Yamanaka, a shallow lake located at the foot of Mt. Fuji. Here, we discuss the influence of the Hōei eruption on the lacustrine sedimentation of Lake Yamanaka using high resolution geophysical and geochemical measurements on gravity cores....

• In large rivers, fish ontogenic development success is mainly influenced by resource availability and by the possibility of species to adapt their diet (i.e. trophic niche). Humans have drastically modified freshwater habitats, notably for navigation purposes. Such modifications may reduce food availability for young of the year (YOY) fish and, c...

Concentrations of organohalogenated contaminants (OHCs) can show significant temporal and spatial variation in the environment and wildlife. Most of the variation is due to changes in use and production, but environmental and biological factors may also contribute to the variation. Nestlings of top predators are exposed to maternally transferred OH...

Tuleariocaris holthuisi and Arete indicus are two ectocommensal shrimps closely associated with the tropical sea urchin Echinometra mathaei. This study provides a comparison of these two E. mathaei symbiotic crustaceans and particularly focuses on the relationship between T. holthuisi and its host’s pigments (i.e. spinochromes), and its dependency...