Clay minerals in chilled or brecciated margins (altered glass) and massive inner crystalline parts (mesostasis) of three basalt-hawaiite bodies from Mururoa Atoll (French Polynesia) have been studied in order to compare their chemical and mineralogical compositions. Polyphase assemblages comprise di- and trioctahedral phases, both of which consist of non-expandable layers (chlorite, celadonite) and two types of expandable layers (saponite and Fe-rich smectite or ‘nontronite-like’ material). The presence of the Fe-rich clays is supported by the presence of the X-ray diffraction 060 peak at 1.51–1.52 Å and of the infrared absorption bands at 875 and 822 cm−1 (Fe3+-Al-OH and Fe3+-Fe3+-OH groups, respectively). The chemical composition of the Fe-rich smectites does not fit with the theoretical nontronite field. The layer charge averages 1 per Si4O10 making these Fe-rich smectites close to ‘celadonite-type’ clays. This could explain the presence of mixed-layer celadonite-smectite. Plotted in an M+/4Si vs. Fe/sum octahedral cations diagram, the chemical compositions of clay minerals in the mesostasis form a continuous field limited by the celadonite-high-charge nontronite-like smectite and chlorite end-members. The clay assemblages are different from those formed in hydrothermal systems or low-grade metamorphic conditions which are characterized by the sequence: saponite → randomly ordered chlorite-smectite mixed-layered minerals (MLMs) → corrensite → chlorite. The systematic presence of Fe-rich clays either in the altered chilled margins or in the massive inner parts of the basalt-hawaiite bodies (high-charge nontronite-like smectite and mixed-layer nontronite-celadonite) makes the Mururoa sea-mount a potential terrestrial analogue for Mars surface exploration.

The clay minerals formed in chilled margins and massive crystallized inner parts of three basalt-hawaiite bodies of Mururoa Atoll (French Polynesia) exhibit contrasting textures. Glass alteration textures are observed around fractures crosscutting the quenched margins: Fe-rich clays grow inward into the glass (retreating surface) while Mg-rich clays grow outward (open space). The textures of clay deposits filling the diktytaxitic voids (mesostasis) in the massive inner parts of the three volcanic bodies are different: unoriented clay matrix with embedded euhedral apatite and pyroxene microcrysts (submarine flow); pallisadic clays coating the void walls and the crystal surfaces of apatite and K-feldspar microcrysts (subaerial flow); and clay muffs covering all the apatite needles, with the central part of the void remaining empty (dike). The unoriented texture could result from the alteration of a glass precursor concomitant with the olivine phenocrysts (clay pseudomorphs). However, such an alteration implies important chemical transfers which are not observed. The pallisadic and muff textures form through heterogeneous nucleation on the solid surfaces and crystal growth from a saline solution. No glass precursor existed. As the center of the diktytaxitic voids in the dike is empty, the residual liquid was probably boiling. The amounts of light rare earth elements (LREE), Sr, and the most incompatible elements are greater in clays from diktytaxitic voids relative to the amounts formed in the altered glass of the chilled margins. Thus, diktytaxitic clays formed from a residual liquid which gave either an evolved glass or a saline solution after cooling (fractionation process). The δ18O variation vs. loss on ignition (LOI) indicates that sea water was involved either in rock alteration or magma contamination. This is confirmed by the 87Rb/86Sr ratio of bulk rocks and clay fractions from the quenched and massive inner parts of the three volcanic bodies which do not fit with the 11.5 Ma isochron indicating that the Rb-Sr system was not closed at any stage during the magmatic history.

In this article I analyze stories about the negotiation of European racialization ideologies in the Society Islands (Tahiti and its Islands) in the late eighteenth century. My focus is the disjunctures between European understandings of their encounters at Tahiti, and what Pacific scholars have come to understand of Polynesian understandings of themselves and various foreigners in that early period. In doing so, I draw out the ways sexuality and gender mediated, enabled, and were also constituted through such racialization processes in their cultural and historical specificity. A key point of departure for this analysis is that the embodiment of race is a negotiated social process. The comparative historical case study I offer up here follows current scholarly moves in seeking out the insights to be gained by tracking racialization as a contingent process, as open rather than closed, as variegated rather than singular, and as imperfectly and only tenuously wrought through ideologies that may be profoundly unanticipated from the vantage point of modernist logics of essentialism and foundationalism. The resulting analysis aims to create space for critically revisiting the ways in which racial normativities and racialized embodiment operate, and how they work, and fail to work, to promote naturalized racist hierarchies of privilege and subordination.

A new record of a white humpback whale (Megaptera novaeangliae) was made off Papeete, Tahiti in July 2019. The individual was completely white, except for grey patterns on its body and on the ventral part of the fluke. The presence of different colourations indicates that this individual is not an albino but a leucistic individual. According to field observations, the individual was likely a juvenile or a subadult. It was seen breaching several times and travelled further north of Papeete, where the animal was recaptured off Arue. White individuals are rare and offer unique opportunities to understand whale movement patterns and potential population connectivity among humpback whale populations.

Responses of corals to seawater acidification have been extensively studied. Sensitivity varies widely between species, highlighting the need to avoid extrapolation from one to another to get an accurate understanding of coral community responses. We tested the responses of seven coral species (Acropora cytherea, Acropora hyacinthus, Acropora pulchra, Leptastrea pruinosa, Montipora grisea, Pavona cactus, Pocillopora verrucosa) from the Mo'orea lagoon to a 48-day exposure to three pH scenarios (pH 7.95, 7.7 and 7.3). Tissue necrosis, mortality, growth rates, photophysiological performances and colour index were recorded. Few significant differences were noted between pH 7.95 and 7.7, but species-specific responses were observed at pH 7.3. While our data do not allow identification of the mechanisms behind this diversity in response between species inhabiting the same environment, it can exclude several hypotheses such as local adaptation, skeletal type, corallum morphology or calcification rate as sole factors determining coral sensitivity to pH.

Classified as Critically Endangered, the Ultramarine Lorikeet Vini ultramarina is one of the world’s most threatened lorikeet species. Endemic to the Marquesas Islands in French Polynesia, the species was formerly distributed over most islands in the archipelago, but is today found primarily on the island of Ua Huka, its range having contracted significantly in recent decades. Habitat alteration and loss, and over-exploitation of natural resources, are cited as impacting the Ultramarine Lorikeet, but the influence of introduced black rats Rattus rattus as predators has been implicated as the primary threat to the species. To assess population status and document aspects of the species biology, including habitat preferences and diet, we conducted the first systematic surveys of the species during two independent surveys spaced seven years apart (2002 and 2009). Population estimates of 2,011 ± 284 (in 2002) and 1,922 (in 2009) individuals on Ua Huka suggest the population was relatively healthy and stable between these periods. However, surveys and searches of other islands in the species’ contemporary range, where black rats occur, either failed to document the species or noted very few individuals. These findings highlight the critical importance of Ua Huka as a rat-free refuge and the value of our surveys as baseline estimates of the population status of the species. We discuss the conservation implications of our findings and propose recommendations to secure the species’ future survival.

The study focuses on the distribution of B, Be, Li, rare earth elements (REE), high-field-strength elements (HFSE), Th, U and Pb in fresh and hydrothermally altered ocean island basalts (OIB) from French Polynesia, and evaluates B/Be and Li/Be ratios as potential tracers of subducted components in the mantle. Hydrothermal solutions affecting the rocks during cooling were derived from meteoric water, sea water and magmatic fluids. The concentrations of REE, HFSE, Th and Be in the OIB were not affected by secondary processes except during advanced stages of subaerial hydrothermal alteration where saponite was a dominant secondary phase. This alteration modified the contents of these elements, changed REE patterns and produced a positive Ce anomaly. The subaerial and submarine hydrothermal alteration (T ∼ 70–100°C) may change U concentrations in OIB, whereas Pb was only marginally redistributed during alteration.

Boron was enriched during submarine and subaerial hydrothermal alteration but was not noticeably affected in basalts altered by magmatic fluids at T > 200°C. Like B, the mobility of Li during the alteration varies with fluid temperature. Lithium became enriched in the basalts during advanced stages of lower T hydrothermal alteration (<100°C). However, this element was partly removed from the rocks during higher T alteration (>200°C) by magmatic fluids. Boron, Be and Li behave as incompatible trace elements in basaltic magmas. Beryllium content in primitive mantle is estimated to be 0.07 ppm. Fresh Polynesian OIB have low abundances of B and Li and low B/Be (2–5) and Li/Be (2.5–5) ratios compared with volcanic arc rocks, marine sediments and altered oceanic crust. Various OIB including even those which have HIMU- and EM-affinities have similar overlapping B/Be and Li/Be ratios. Both B and Li are probably stripped from a lithospheric slab during subduction-related metamorphism and are, thus, not involved in deep mantle recycling. The mantle-normalized trace element abundances of MORB and OIB usually display patterns characterized by negative B, Pb and Li anomalies. The patterns of continental crust and crustal rocks have distinct positive anomalies for these elements whereas continental basaltic rocks have variable relative abundances of B, Pb and Li. The anomalies of these elements in basalts can be useful in discriminating their tectonic setting and constraining the mantle source regions of basalts.

The timing and origin of Zika virus (ZIKV) introduction in Brazil has been the subject of controversy. Initially, it was assumed that the virus was introduced during the FIFA World Cup in June–July 2014. Then, it was speculated that ZIKV may have been introduced by athletes from French Polynesia (FP) who competed in a canoe race in Rio de Janeiro in August 2014. We attempted to apply mathematical models to determine the most likely time window of ZIKV introduction in Brazil. Given that the timing and origin of ZIKV introduction in Brazil may be a politically sensitive issue, its determination (or the provision of a plausible hypothesis) may help to prevent undeserved blame. We used a simple mathematical model to estimate the force of infection and the corresponding individual probability of being infected with ZIKV in FP. Taking into account the air travel volume from FP to Brazil between October 2013 and March 2014, we estimated the expected number of infected travellers arriving at Brazilian airports during that period. During the period between December 2013 and February 2014, 51 individuals travelled from FP airports to 11 Brazilian cities. Basing on the calculated force of ZIKV infection (the per capita rate of new infections per time unit) and risk of infection (probability of at least one new infection), we estimated that 18 (95% CI 12–22) individuals who arrived in seven of the evaluated cities were infected. When basic ZIKV reproduction numbers greater than one were assumed in the seven evaluated cities, ZIKV could have been introduced in any one of the cities. Based on the force of infection in FP, basic reproduction ZIKV number in selected Brazilian cities, and estimated travel volume, we concluded that ZIKV was most likely introduced and established in Brazil by infected travellers arriving from FP in the period between October 2013 and March 2014, which was prior to the two aforementioned sporting events.

Individual Pinctada margaritifera molluscs were collected from the Takapoto atoll (Tuamotu Archipelago, French Polynesia) and used to produce ten first generation full-sib families in a hatchery system, following artificial breeding protocols. After three years of culture, these progenies were transferred to Rangiroa atoll (Tuamotu Archipelago, French Polynesia) and tested for their potential as graft donors. A large-scale grafting experiment of 1500 grafts was conducted, in which a single professional grafter used ten individual donor oysters from each of the ten families, grafting 15 recipient oysters from each donor. The recipient oysters were all obtained from wild spat collection in Ahe (Tuamotu Archipelago, French Polynesia). After 18 months of culture, 874 pearls were harvested. Highly significant donor family effects were found for nucleus retention, nacre thickness, nacre weight, pearl colour darkness and visually-perceived colour (bodycolor and overtone), pearl shape categories, surface defects and lustre, the last two of which are components of the Tahitian classification grade. No significant difference was recorded between the ten G1 families for the absence or presence of rings. The progenies could be ranked from “best” (i.e., the donor whose grafts produced the greatest number of grade A pearls) to the “worst”. Some progenies had extreme characteristics: family B presented the greatest number of pearls with lustre (98%) and a high proportion of dark gray to black with green overtone pearls (70%). These results have important implications for the selective breeding of donor pearl oysters: it may be possible to reach a point where specific donor lines whose grafts produce pearls with specific quality traits could be identified and maintained as specific breeding lines.

Producing high quality cultured black pearls from Pinctada margaritifera is one of the major challenges for the “pearl oyster” industry in French Polynesia. In order to assess donor effect on cultured pearl quality, wild Pinctada margaritifera originating from the Tuamotu Archipelago were used in a duplicated grafting experiment. After 12 months of culture, nucleus retention was assessed and seven pearl quality traits recorded on the 454 cultured pearls harvested from the experiment. The traits scored were nacre thickness and pearl weight, surface defects, lustre, grade, and the colour components: 1) darkness of cultured pearl colour, and 2) visual perception of colour class (bodycolor and/or overtone). Our results demonstrate for the first time that individual wild donors of implanted mantle grafts significantly affect these seven quality traits in P. margaritifera cultured pearls. This finding was repeated in two series of grafts made by different professional grafters. The wild donors could be ranked from “best” (e.g., the donor whose grafts produced the cultured pearl with the maximum lustre) to the “worst”. Moreover, we showed strong correlations between: 1) cultured pearl nacre thickness and grade, with grade A showing the greatest nacre thickness on average compared with grade D and rejects; and 2) nacre thickness/cultured pearl weight and colour components (darkness and visual “colour categories”), with the palest cultured pearls (i.e. white cultured pearls) being the smallest (lowest nacre thickness and weight). Thus, one way of enhancing P. margaritifera foundation stocks for a selective breeding program could be to select the “best” donors, using appropriate molecular tools. Generation of selected donor lines from these stocks through hatchery production would be one way to increase the quality of cultured pearl farming of P. margaritifera in French Polynesia.

Columbidae (pigeons and doves) is one of the most threatened bird families in the world. I analysed data on the BirdLife International Species Information Database to examine the distribution and causes of threat among columbids. Of 304 species extant in the wild, 59 (19%) are threatened with extinction, 48 (83%) of which have restricted ranges. All but two threatened columbid species (97%) inhabit tropical forests, and of these, 45 are island species (78% of all threatened columbid species). The taxonomic distribution of columbids follows three coherent areas: the Americas; Europe, Africa, the Middle East and Central Asia; Asia, Australasia and Oceania. Asia, Australasia and Oceania support nearly two-thirds of all extant species and three-quarters of threatened species (44), most of which (84%) are restricted range insular species. Three countries within this area are the most important for the conservation of columbid diversity: Indonesia, the Philippines and French Polynesia. Together these three countries support 40% of extant species and half of all threatened species. The greatest causes of threat to columbids are (1) habitat loss and fragmentation due to agriculture and extraction, (2) hunting for food, and (3) alien predator species. Habitat loss and fragmentation are universal threats to columbids. Hunting, however, is a significantly greater threat to species in Asia, Australasia and Oceania than to species in the other two areas and urgently needs to be addressed. I discuss the conservation implications of these findings and make research recommendations to aid and encourage the conservation of threatened columbids and their habitats.

New excavations and survey on the island of Rapa have shown that a rockshelter was occupied by early settlers around AD 1200 and the first hill forts were erected about 300 years later. Refortification occurred up to the contact period and proliferated around AD 1700. Taro cultivation in terraced pond-fields kept pace with the construction of forts. The authors make a connection between fort-building and making pond-fields, demonstrating that the pressure on resources provoked both the intensification of agriculture and hostility between the communities of the small island.

Généralités. La Polynésie française est présentée sur le plan géographique : description des archipels, du climat et de la population. Quelques aspects de l’économie. Les principales activités économiques sont abordées pour situer les productions fruitières dans leur contexte. État des lieux des productions fruitières. La production fruitière est présentée selon la nature et les quantités ; la typologie des exploitations et les spécificités de la production des différents archipels sont décrites. Facteurs conditionnant le développement des productions. Le développement des cultures fruitières dépend de nombreux facteurs qui doivent être analysés : contexte phytosanitaire, production de matériel végétal, problèmes fonciers, organisation de la profession, technicité des agriculteurs, aides publiques et possibilités de transformation sont déterminants. Conclusion. Les actions récentes qui ont été mises en place permettent une évolution favorable de la filière.

Contexte et présentation du projet. Après un bref historique et un aperçu général de l’arboriculture fruitière en Polynésie française, le fonctionnement et les opérations programmées sur 3 ans d’un projet d’appui mené de 2002 à 2005 sont présentés. Réalisation. Les cinq thèmes principaux d’intervention sont successivement décrits : amélioration du matériel végétal ; recherches d’accompagnement ; formation, vulgarisation et encadrement : volet complété par la rédaction de documents techniques ; missions d’appui et stages ; démarche qualité et organisation de la profession, complété par un volet de valorisation des produits par transformation. Les résultats et les moyens utilisés sont analysés. Discussion et conclusion. Les avantages et inconvénients rencontrés dans la réalisation du projet sont discutés et permettent de proposer quelques améliorations dans la mise en œuvre de projets analogues.

The characteristics of the phytoplankton of Takapoto Atoll are reviewed from the studies conducted between 1974 and 1998. These studies mainly concerned the biomass and primary production of phytoplankton while the taxonomic composition received far less attention. The mean biomass is 0.2–0.3 μg chl a·L–1. The phytoplankton is homogeneously distributed on a year scale although an higher biomass (0.8 μg chl a·L–1) may temporarily exist in the south part of the atoll under moderate tradewinds or calm weather. The gross primary production reached 0.8 g C·m–2·day–1 whereas the net primary production is estimated to be 0.7 g C·m–2·day–1. No significant long-term changes of the biomass or primary production can be observed. The implications of this stability are discussed in the context of the mother-of-pearl mariculture. Size fractionated samples revealed the predominance of picophytoplankton which represented more than 60% of the phytoplankton biomass and achieved > 50% of the primary production. The taxonomic composition observed in 1974 showed the predominance of three algal groups: diatoms, dinoflagellates and coccolithophorids. The diatoms were the most diversified group, while the dinoflagellates were the most abundant. No further examination of the phytoplankton was undertaken until 1996. At that time, the microplankton was quite absent, and the phytoplankton communities were dominated by the pico- and nanophytoplankton, mainly chlorophytes, prymnesiophytes and dinoflagellates. This drastic shift of the phytoplankton communities towards smaller size is not clearly understood. It emphasises the need of taxonomic studies for a better understanding of the lagoon ecology.

This article describes tracking experiments conducted on eleven yellowfin tuna using ultrasonic transmitters in French Polynesia between 1985 and 1997. Nine fish were caught near Fish Aggregating Devices (FADs) while the other two were tracked in coastal areas without FADs. The fish showed different patterns of horizontal movements: tight associations with FADs lasting several days, foraging movements confirmed by simultaneous acoustic observations of prey-sized fauna, movements parallel to the shore, and traveling between FADs. This intra- and inter-individual variety of behaviour might depend on the local environment (prey), and on individual biological differences. The influence of FADs, coastlines, and prey on tuna movements is discussed. The lack of information about the surrounding environment, the internal state of the fish and the recent history of the fish usually prevent scientists from adequately interpreting the observed movements. Ideas for future research to studying tuna behaviour near FADs are discussed.

Eighty-seven two-hour acoustic surveys (radius 0.8 nautical mile, vertical range 0–500 m) around 17 fish aggregating devices (FADs) were conducted in French Polynesia between December 1995 and February 1997. Associated tuna densities were calculated using two different techniques: echo counting when the fish had sufficient distances from each other and echo integration when the fish swam close together (in schools). No acoustic detection of tuna was observed during 27 of the 87 surveys, representing 81 % of all the nocturnal surveys and 15 % of the diurnal ones. The 60 other surveys showed three different classes of aggregations: (1) ‘deep scattered fish’, observed 45 times, (2) ‘intermediate scattered fish’, observed 16 times, and (3) ‘shallow schooling fish’, observed 16 times. Sometimes aggregations of different classes were observed beneath the same FAD. The size of the fish inside the aggregations (determined from target strength values), the distance between the individuals, and the depth of the fish all decreased from ‘deep scattered fish’ to ‘shallow schooling fish’ (100–300 m for ‘deep scattered fish’, 50–150 m for ‘intermediate scattered fish’, and above the depth of 50 m for ‘shallow schooling fish’). Fish densities also varied according to the class of aggregations: 7.3, 26, and 801 fish per km3 on average for ‘deep scattered fish’, ‘intermediate scattered fish’, and ‘shallow schooling fish’, respectively. The highest densities were observed during daytime, while night-time observations indicated a variety of situations, from the absence of individuals to large amounts of fish.

The gametogenic cycle and the reproductive effort of the blacklip pearl oyster, Pinctada margaritifera, cultivated in Takapoto lagoon were studied for a 1-year period (March 1997–April 1998) by bimonthly observations of gonadal sections, dry tissue weights and gonadal index in a population of pearl oyster composed of three age-groups. Pearl oysters attained sexual maturity in the end of their first year (height ≈ 40 mm), implying that P. margaritifera is a late-maturing species in comparison with other Pteriidae. This species was also confirmed to be a marked protandrous successive hermaphrodite in culture, with 100 % of males at first maturity and 75 % in older pearl oyster (height > 120 mm). The general pattern of gametogenic activity, fairly synchronous in both sexes, was comparable with that of other tropical bivalves: reproduction occurs continuously throughout the year with a maximal activity during the warm season (November–May). No resting period was observed. Quantitative growth data showed that P. margaritifera exhibits an annual synchronised polymodal spawning pattern, with two spawning peaks in age-group I (height ≈ 70 mm) and five in age-groups II (height ≈ 100 mm) and III (height ≈ 120 mm). Spawning was sometimes incomplete, nevertheless a clear relationship between gamete production (PR, g) and size (height H, mm) was obtained: PR = 5.26 × 10–7 H2.91 (R[sup2 ] = 0.99, P < 0.05). Estimation of PR was used to calculate the annual reproductive effort in P. margaritifera. Reproductive effort (%) was similar to those calculated for temperate species and showed a progressive increase with the age of pearl oyster, from 7 % in age-group I to 38 % in age-group III. This study showed that, in a fairly stable tropical environment such as the Takapoto lagoon, P. margaritifera is a multiple spawner, which uses an opportunistic reproductive strategy, allowing investment, all year around, of any surplus energy into gamete production. Surplus energy is ensured by the high pumping rates developed by this non-symbiotic bivalve to succeed in low seston conditions.