Claire Goiran

University of New Caledonia | UNC · ISEA

Seawater temperature rise is damaging coral reef ecosystems. There is growing evidence for the negative impact of rising temperatures on the survival of adult corals and their reproductive success. However, the effect of elevated temperatures on gametes remains scarcely studied. Here we tested the effect of the thermal priming of gametes on the fer...

The capacity for individuals to move long distances can profoundly influence how species are affected by localised threatening processes. Previous studies on the movement patterns of sea snakes have highlighted the highly site-attached nature of some species, but constraints on collecting data at large spatial and temporal scales have underestimate...

The evolution of bright ‘warning’ colours in nontoxic animals often is attributed to mimicry of toxic species, but empirical tests of that hypothesis must overcome the logistical challenge of quantifying differential rates of predation in nature. Populations of a harmless sea snake species ( Emydocephalus annulatus ) in New Caledonia exhibit colour...

The first survey of sea snakes (Elapidae, Hydrophiinae) at the remote Entrecasteaux atolls, Coral Sea, was conducted using remote unbaited 360° video cameras (RUV360), in 2021. We detected 49 snakes belonging to at least six species (Aipysurus duboisii, A. laevis, Hydrophis coggeri, H. macdowelli, H. major and H. ornatus) at the two largest atolls,...

Modern nautilids ( Nautilus and Allonautilus ) have often been studied by paleontologists to better understand the anatomy and ecology of fossil relatives. Because direct observations of these animals are difficult, the analysis of light stable isotopes (C, O) preserved in their shells has been employed to reveal their habitat and life history. We...

Status of soft bottom habitats and megafauna of Entrecasteaux atolls, New Caledonia

Life-history traits such as rates of growth, survival and reproduction can vary though time within a single population, or through space among populations, due to abiotically-driven changes in resource availability. In terrestrial reptiles, parameters such as temperature and rainfall generate variation in life-histories—but other parameters likely...

Evolutionary theory suggests that polymorphic traits can be maintained within a single population only under specific conditions, such as negative frequency-dependent selection or heterozygote advantage. Non-venomous turtle-headed sea snakes (Emydocephalus annulatus) living in shallow bays near Noumea in New Caledonia exhibit three colour morphs: b...

For sea snakes as for many types of animals, long-term studies on population biology are rare and hence, we do not understand the degree to which annual variation in population sizes is driven by density-dependent regulation versus by stochastic abiotic factors. We monitored three populations of turtle-headed sea snakes ( Emydocephalus annulatus )...

In snakes, divergence in head size between the sexes has been interpreted as an adaptation to intersexual niche divergence. By overcoming gape-limitation, a larger head enables snakes of one sex to ingest larger prey items. Under this hypothesis, we do not expect a species that consumes only tiny prey items to exhibit sex differences in relative he...

Evolutionary transitions from terrestrial to aquatic habitats involve major selective shifts in animal signalling systems. Entirely marine snakes face two challenges during underwater social interactions: (1) finding mates when pheromones are diffused by water currents; and, once a mate is located, (2) maintaining contact and co-ordinating mating w...

1. Research on interactions between humans and deadly snakes has focused on situ- ations that result in high rates of snakebite; but we can also learn from cases where snakes and people coexist peacefully. For example, coastal bays near Noumea, in the Pacific archipelago of New Caledonia, are used by thousands of tourists and snakes, but bites are...

Morphological features that impair a predator's ability to consume a prey item may benefit individual prey; but what of features that prolong prey‐handling but do not enhance prey survival? For example, a striped eel catfish Plotosus lineatus will be fatally envenomated if struck by its specialist predator, the greater sea snake Hydrophis major. No...

Although sea snakes are important predators in coral reef ecosystems and have undergone substantial population declines in some areas, we have little robust information on life histories of these animals. Based on a 17-yr mark–recapture study of turtle-headed sea snakes (Emydocephalus annulatus) in New Caledonia (> 1200 individuals marked), we can...

The fitness of a predator depends upon its ability to locate and capture prey; and thus, increasing dietary specialization should favor the evolution of species-specific foraging tactics tuned to taxon-specific habitats and cues. Within marine environments, prey detectabil-ity (e.g., via visual or chemical cues) is affected by environmental conditi...

Coral reef ecosystems are declining at an alarming rate. Increasing seawater temperatures and occurrence of extreme warming events can impair sexual reproduction in reef-building corals and inhibit the ability for coral communities to replenish and persist. Here, we investigated the role of photophysiology on the reproductive ecology of Pocillopora...

Tidal cycles are known to affect the ecology of many marine animals, but logistical obstacles have discouraged behavioural studies on sea snakes in the wild. Here, we analyse a large dataset (1,445 observations of 126 individuals) to explore tidally-driven shifts in the behaviour of free-ranging turtle-headed sea snakes (Emydocephalus annulatus, Hy...

We describe a new species of turtle-headed sea snake Emydocephalus orarius sp. nov. (Elapidae) from Western Australia’s Coral Coast, Pilbara and Kimberley regions. Phylogenetic analysis of mitochondrial markers places the new species as the sister lineage to the two currently recognised species in Emydocephalus: E. annulatus from the Timor Sea reef...

In defence of their nests or territories, damselfish (Pomacentridae) attack even large and potentially dangerous intruders. The Indo-Pacific region contains many species of sea snakes, some of which eat damselfish whereas others do not. Can the fishes identify which sea snake taxa pose a threat? We recorded responses of damselfishes to natural enco...

In many populations of terrestrial snakes, the phenotype of an individual (e.g. body size, sex, colour) affects its habitat use. One cause for that link is gape limitation, which can result in larger snakes eating prey that are found in different habitats. A second factor involves thermoregulatory opportunities, whereby individuals select habitats...

We describe initial results of an innovative citizen science project that is unusual in its taxonomic focus (deadly sea snakes), its location (the Indo‐Pacific), and its primary contributors (grandmothers from the city of Noumea, New Caledonia).

An aquatic animal faces challenges not encountered by its terrestrial counterparts, promoting adaptive responses in multiple traits. For example, a thicker dermis might protect snakes when they are pushed against sharp objects by water currents, and might enable a snake to shed fouling organisms attached to its skin. We thus predicted that marine s...

Although widespread, the large Hydrophiinae sea snake Hydrophis major is poorly known ecologically. We dissected 119 preserved specimens in museum collections to quantify body sizes and proportions, sexual dimorphism, reproductive biology and diet. The sexes mature at similar snout–vent lengths (SVLs, about 75 cm) and attain similar maximum sizes (...

Without drastic efforts to reduce carbon emissions and mitigate globalized stressors, tropical coral reefs are in jeopardy. Strategic conservation and management requires identification of the environmental and socioeconomic factors driving the persistence of scleractinian coral assemblages—the foundation species of coral reef ecosystems. Here, we...

Common in Vanuatu, the Dwarf Sea Krait Laticauda frontalis also is known from five old records (in the 1880s and 1890s) from the Loyalty Islands, between Vanuatu and the main island of New Caledonia. Those records have been interpreted by some authorities as errors, or as reflecting occasional waifs rather than breeding populations. We now report a...

Marine snakes represent the most speciose group of marine reptiles and are a significant component of reef and coastal ecosystems in tropical oceans. Research on this group has historically been challenging due to the difficulty in capturing, handling, and keeping these animals for field-and lab-based research. Inexplicable declines in marine snake...

Rising temperature can adversely affect specific functions of corals. Coral gametes and planulae of Acropora pulchra were evaluated to determine their temperature resistances, and the potential of developmental thermal acclimation was examined on gametes. Results highlight that fertilization success displays a relatively high thermal resistance at...

Although classically associated with urban environments in invertebrates, melanism in terrestrial snakes is more often linked to occupancy of cool climates [1–3]. Thermal advantages to melanism do not apply in aquatic snakes [4], but although turtle-headed seasnakes (Emydocephalus annulatus) are banded or blotched across a wide geographic range [5]...

A wide investigation was conducted into the main organic matter (OM) sources supporting coral reef trophic networks in the lagoon of New Caledonia. Sampling included different reef locations (fringing, intermediate and barrier reef), different associated ecosystems (mangroves and seagrass beds) and rivers. In total, 30 taxa of macrophytes, plus poo...

Inorganic nutrients play a critical role in determining benthic community structure in tropical seas. This study examined the impact of adding inorganic nutrients (ammonium and phosphate) on the isotopic composition of 2 reef-building corals, Pocillopora damicornis and Heliofungia actiniformis, on the southern Great Barrier Reef. The addition of el...

Exploration of a landlocked cenote on Lifou (Loyalty Islands) revealed 37 shells of the cephalopod Nautilus macromphalus Sowerby, 1849, in saltwater on the cenote floor, approximately 40 m below the water surface. The occurrence of these shells is unusual because N. macromphalus is restricted to the open marine waters surrounding the island. All of...

On coral reefs in New Caledonia, the eggs of demersal-spawning fishes are consumed by turtle-headed seasnakes (Emydocephalus annulatus). Fish repel nest-raiding snakes by a series of tactics. We recorded 232 cases (involving 22 fish species) of antipredator behaviour towards snakes on a reef near Noumea. Blennies and gobies focused their attacks on...

Shells of the cephalopod Nautilus macromphalus were collected in 2011 from three bays on the island of Lifou in the South Pacific six months after a tropical cyclone passed over the island. All three bays were on the east side of the island; Bays 1 and 2 were 200 m apart whereas Bay 3 was 25 km to the north. Nautilus shells in Bays 1 and 2 were stu...

See at : https://gsa.confex.com/gsa/2013AM/webprogram/Paper226427.html

In terrestrial snakes, many cases of intraspecific shifts in dietary habits as a function of predator sex and body size are driven by gape limitation and hence are most common in species that feed on relatively large prey and exhibit a wide body-size range. Our data on sea snakes reveal an alternative mechanism for intraspecific niche partitioning,...

Le cénote d'Ani-e-Wee renferme un gisement exceptionnel des plus anciens nautiles endémiques de Nouvelle-Calédonie. Son étude livre des indices sur la formation des karsts de Lifou depuis au moins 140 000 ans. La tectonique régionale et les variations successives du niveau des océans depuis le Pléistocène semblent à l'origine de la karstification d...

Populations of widespread species often differ in phenotypic traits, although rarely in such a dramatic fashion as revealed by research on turtle‐headed seasnakes (Emydocephalus annulatus). These snakes are highly philopatric, with mark–recapture studies showing that the interchange of individuals rarely occurs even between two adjacent bays (separ...

Monitoring results from a small reef (Ile aux Canards) near Noumea in the New Caledonian Lagoon reveal that numbers of turtle-headed sea snakes (Emydocephalus annulatus) have been in consistent decline over a 9-year period, with average daily counts of snakes decreasing from >6 to <2 over this period. Causal factors for the decline are unclear, bec...

Thirty-two samples of submerged Nautilus macromphalus shells were recovered in 2008 from Lifou, Loyalty Islands in the South Pacific Ocean. Specimens were collected from carbonate-dominated sediment in water depths of 1–3 m. Some specimens were partly buried, whereas others rested on the seafloor. The majority of the specimens (66%) were recovered...

Thirty-two samples of submerged Nautilus macromphalus shells were recovered in 2008 from Lifou, Loyalty Islands in the South Pacific Ocean. Specimens were collected from carbonate-dominated sediment in water depths of 1-3 m. Some specimens were partly buried, whereas others rested on the seafloor. The majority of the specimens (66%) were recovered...

The discovery of 11 Nautilus macromphalus shells in marine environments near New Caledonia constitutes the first opportunity for taphonomic analysis of empty shells of unburied, externally shelled cephalopods on the seafloor. Radiometric dating indicates specimen ages range from 14 to 42 years. These modern specimens provide a unique opportunity to...

The discovery of 11 Nautilus macromphalus shells in marine environments near New Caledonia constitutes the first opportunity for taphonomic analysis of empty shells of unburied, externally shelled cephalopods on the seafloor. Radiometric dating indicates specimen ages range from 14 to 42 years. These modern specimens provide a unique opportunity to...

Adlardia novaecaledoniae n. g., n. sp. (Digenea: Cryptogonimidae) is described from the fish Nemipterus furcosus (Val.) (Perciformes: Nemipteridae) from off New Caledonia (South Pacific). Adlardia n. g. is distinguished from all other cryptogonimid genera by the combination of an elongate body, the presence of oral spines, intestinal caeca that ope...

The evolutionary success of reef-building corals in nutrient-poor tropical waters is attributed to endosymbiotic dinoflagellates. The algae release photosynthetic products to the coral animal cells, augment nutrient flux, and enhance the rate of coral calcification. Natural abundance of stable isotopes (delta13C and delta18O) provides answers to mo...

Inorganic nutrients play a critical role in determining benthic community structure in tropical seas. This study examined the impact of adding inorganic nutrients (ammonium and phosphate) on the isotopic composition of 2 reef-building corals, Pocillopora damicornis and Heliofungia actiniformis, on the southern Great Barrier Reef. The addition of el...

Dinoflagellates which live in intracellular symbiosis with corals (zooxanthellae), probably share the ionic conditions of their host cells, i.e. are subjected to lower sodium and calcium concentrations than ambient seawater. Although free-living zooxanthellae are not generally found in waters of reef ecosystems, they can be released in either a con...

Mechanisms of HCO3− uptake as a source of dissolved inorganic carbon (DIC) for photosynthesis by the intracellular symbiont, Symbiodinium sp. were studied using microcolonies of the coral Galaxea fascicularis, freshly isolated zooxanthellae (FIZ) and cultured zooxanthellae (CZ). For this purpose we used specific inhibitors of anion transport 4-acet...

The aim of this and the accompanying paper is to investigate the mechanisms of dissolved inorganic carbon (DIC) uptake by the scleractinian coral Galaxea fascicularis, and its delivery to the endosymbiotic photosynthetic dinoflagellates (zooxanthellae). For this purpose, a comparison was made between the photosynthetic performance of zooxanthellae...