Rare earth elements (REEs) are increasingly recognized as emerging contaminants, yet field data remain scarce for tropical marine ecosystems and for seabird matrices beyond feathers. Here, we present a multi-matrix assessment of REEs across a tropical oceanic-coastal gradient in the South Atlantic, including, to our knowledge, the first measurements of REEs in seabird blood and eggs. We analyzed 311 samples including brown booby (Sula leucogaster) blood, feathers and eggs, fish muscle and liver, and crab muscle from a remote oceanic archipelago (SPSPA) and a nearshore coastal archipelago (Santana). ΣREE in seabird samples differed among matrices, with feathers generally showing higher median values than blood and eggs, underscoring matrix-specific integration of exposure. Spatial patterns were also matrix- and age-dependent: blood ΣREE showed no consistent site contrast, feather differences between sites were largely restricted to juveniles, and eggs showed higher ΣREE at Santana, indicating that maternal transfer provides a clear pathway for expressing site-specific exposure signals. In fishes, interspecific differences were detected at SPSPA in both liver and muscle, whereas no among-species difference was detected for muscle at Santana; liver often exceeded muscle, consistent with tissue-dependent accumulation. A screening-level dietary assessment indicated negligible carcinogenic risk from ΣREE exposure via edible fish muscle under adult and child scenarios, with intake distributions far below the provisional tolerable daily intake and zero exceedance probability. Overall, these results expand baseline REE knowledge for tropical marine food webs and highlight seabird eggs as a sensitive matrix for spatial comparisons.

Biological invasions can adversely affect pollinator diversity by threatening the maintenance of animal-pollinated plant communities. Although most studies have examined single invasive species, accelerating species introductions driven by global trade highlight the need to understand how multiple co-occurring invaders jointly influence pollination networks. We leveraged the relative simplicity of the Ogasawara archipelago to assess the combined impacts of multiple invaders on pollination networks. We surveyed floral and pollinator communities and quantified plant-pollinator interactions across four islands with varying degrees of invasion. We characterized invasion degree based on the abundance of three invasive taxa: green anoles (Anolis carolinensis), a predator; western honey bees (Apis mellifera), a floral competitor; and several flowering plants. Structural equation models were used to quantify direct and indirect effects of these invaders on effective plant-pollinator partners (niche breadth or variety of partners a species interacts with in a given community) and the degree of specialization (d', niche partitioning or selectivity of a species) of plant and pollinator communities. All invaders strongly affected pollinator diversity and, to a lesser extent, plant diversity. Anoles had the strongest negative effect on pollinator diversity, triggering cascading effects across the trophic chain. Directly or indirectly, all invaders negatively affected plant resource use. Honey bee abundance had a direct negative effect on plant effective partners and specialization, and anole abundance and the proportion of invasive plants indirectly affected plant resource use through a reduction in pollinator diversity. Degree of invasion and network structure mediated whether honey bees contributed to functional compensation or facilitated invasional meltdown. Our findings demonstrated that co-occurring invaders generated synergistic pressures on pollinators and plants, underscoring the importance of evaluating invasions in a multistressor context. Integrative approaches are essential for developing conservation strategies in vulnerable ecosystems, particularly oceanic islands, where biological invasions are the principal driver of biodiversity loss.

ABSTRACT Early Devonian magmatism in the Minusinsk trough of the Altai–Sayan Large Igneous province provides a critical record of regional geologic history. In this study, we determined the U–Pb baddeleyite isotope age, major and trace element geochemistry, and Sr–Nd isotope composition of igneous rocks in the Uryup sector of Minusinsk trough, with the aim of constraining their magmatic origin. The volcanic succession is divided, from base to top, into three Suites: (1) the Bazyr Suite, composed of basalts, trachybasalts, basaltic trachyandesites, transitional tephrites–trachybasalts, and phonotephrites; (2) the Beresh Suite, consisting of trachybasalts, basaltic trachyandesites, phonotephrites, tephriphonolites, and feldspathoid ijolites; and (3) the Ashpan Suite, comprising basalts, trachybasalts, and basaltic trachyandesites. The Early Devonian age of these Suites, established in previous geological and palaeontological studies, is confirmed here by new U–Pb geochronological data on baddeleyite obtained by ID–TIMS. Rare-element concentrations in all mafic rocks, regardless of alkalinity, vary widely, showing features typical of both oceanic island basalts and island arc basalts. Compared with sub-alkalic counterparts, alkalic mafic rocks contain abundant nepheline phenocrysts (up to 30 wt.%) and are enriched in Na2O, Al2O3, Rb, Ba, Th, U, K, Nb, REE, and radiogenic Sr, while exhibiting similar and only slightly variable radiogenic Nd values. We propose a model in which all Uryup sector rocks were derived from a single sub-alkalic basaltic parental melt generated in the asthenospheric mantle by the influence of a mantle plume on fragments of ancient supra-subduction lithospheric mantle. Geochemical and isotopic variations are inconsistent with a simple comagmatic relationship between sub-alkalic and alkalic rocks or with fractional crystallization as the sole controlling process. Bazyr sub-alkalic basaltic magmas experienced simultaneous fractional crystallization and contamination by silicate crust. Beresh phonotephrites, tephriphonolites, and feldspathoid ijolites formed from differentiated sub-alkalic melts through carbonate contamination, possibly within the continental crust.

Fossils provide invaluable data for evolutionary studies in oceanic islands. The paleontological record of the Macaronesian archipelagos has been the target of many researchers for a long time, with a recent surge in interest in scientific research related to their paleontological heritage. In the Macaronesian Azores archipelago, the marine invertebrate fossil record from the warmest period of the Last Interglacial stage (also known as Marine Isotopic Stage 5e—MIS 5e) represents approximately 95.6% of the total species. In contrast, the MIS 5e marine vertebrate fossil record comprises only four reported species (2.2%), with marine algae accounting for the remaining 2.2% (four species). This study reports on—and adds to the paleobiodiversity of the MIS 5e deposits at Santa Maria Island (Azores Archipelago)—two marine mesopelagic lanternfishes, identified from their otoliths: Diaphus cf. holti Tåning, 1918, and Symbolophorus veranyi (Moreau, 1888). Finally, we offer a plausible explanation for the presence of mesopelagic fishes in the MIS 5e fossiliferous deposits of Santa Maria Island.

A multi-method approach to characterising dynamic human-shark interactions at a remote oceanic island.

Crucial factors determining colonisation patterns of bird species on oceanic islands in the Anthropocene

Risk perception is central to wildlife disease management and informs both public health and conservation strategies. Understanding perceptions of wildlife-related health risks helps public health professionals and conservationists develop effective communication strategies to foster both public safety and species conservation. Reunion Island is a Southwestern Indian Ocean island where human-bat interactions are common, especially with the urban-adapted endemic species Mormopterus francoismoutoui. Concerns about olfactory nuisance and respiratory health impacts resulting from these interactions make perceptions of bat-related sanitary risks especially salient. This study surveyed 768 residents to explore how general opinions and past experiences with bats influence perceived health risks. The mean bat-related health risk perception index (RPI) was 2.87 ± 0.03 on a 5-point scale. Perceived risk was significantly higher among individuals with negative opinions (3.14 ± 0.05) compared to neutral (2.95 ± 0.03) and positive opinions (2.56 ± 0.05; p < 0.001). A similar pattern was observed for past experiences, with negative experiences associated with the highest perceived risk (p < 0.001). Island natives (OR = 2.00) and social interactions about bat-related diseases (OR = 1.49) were the strongest predictors of higher perceived risk. In contrast, trust in science reduced perceived risk (OR = 0.75), while younger respondents reported slightly higher risk perception. These findings highlight the importance of social information networks and scientific trust in shaping perceptions, underscoring the need for clear, targeted, and evidence-based risk communication to promote coexistence and mitigate heightened fears.

ABSTRACT Basaltic volcanism associated with the onset of Gulf of Suez rifting at the end of the Oligocene produced fissure‐fed dykes, sills, and minor lava flows dominated by dolerites and olivine basalts. They crystallised under relatively uniform redox conditions close to the fayalite–magnetite–quartz (FMQ) buffer and show comparable liquidus temperatures (1183°C–1153°C ± 51°C). Thermobarometric estimates indicate magma storage over a broad pressure range (9.3–6 kbar; ~34.9–21.9 km), just above the estimated Moho (~35 km), consistent with episodic cooling and crystallisation. Magma ascent to subvolcanic and near‐surface crustal levels was controlled by neutral buoyancy within the crystalline upper crust. Upon encountering a density barrier, the magmas propagated through the overlying sedimentary succession via mechanical intrusion along fracture systems. Crystallisation followed a sequence from cotectic plagioclase–olivine to eutectic plagioclase–olivine–augite, with late Fe–Ti oxides. Geochemically, the basalts are tholeiitic high Ti–P varieties enriched in high‐field‐strength elements (HFSE) and large‐ion lithophile elements (LILE) and exhibit moderate Mg# values (50–46) together with low Cr and Ni contents. Their mantle source corresponds to an enriched ocean island basalt (OIB)‐like reservoir. Modelling indicates derivation from ~12% to 16% partial melting of a garnet lherzolite, reflecting significant adiabatic decompression from a fertile deep‐mantle source to the conductive thermal boundary layer beneath a thin lithosphere.

Host species as key drivers of Symbiodiniaceae assemblages: Coral and free-living diversity in a Southwestern Atlantic oceanic island.

The species-area relationship (SAR) has long been used to predict extirpation rates from habitat loss, but these rates depend not only on habitat area but also on the surrounding landscape and species' habitat specialization. We collated global data from forest islands created by river damming and forest fragments resulting from clear-cut deforestation to examine the effects of matrix type (aquatic or terrestrial) and tree cover on avian SARs. Unlike oceanic islands, which are often millions of years old, anthropogenic forest islands provide a contemporary analog to forest fragments to understand matrix effects on SARs and serve as a baseline for worst-case scenarios of forest fragmentation. Our database comprises 50 datasets from 45 studies conducted in tropical and subtropical regions, totaling 1,954 bird species detected through 39,197 incidence records from 336 forest islands and 669 forest fragments. We found that bird extirpation rates were lower in fragments than on islands, especially for forest-dependent species compared to all species. Species losses were further reduced by increasing tree cover around forest remnants at local landscape scales of 300 m, highlighting the importance of small-scale conservation strategies. Moreover, even small forest fragments with greater nearby tree cover held high conservation value, emphasizing the crucial role of the surrounding landscape in mitigating avian extirpations from forest remnants. Beyond protecting forest remnants themselves, area-based conservation efforts would therefore be greatly enhanced by improving matrix quality and expanding tree cover in otherwise hostile landscapes.

Clade Ib mpox in southwest Indian Ocean islands

Average benchmark compositions of intraplate basalts with continental and ocean island provenance

Islands represent only 5.3% of the global land area but they are epicenters of biodiversity loss, harboring 37% of critically endangered species. Fernando de Noronha, an archipelago with 21 volcanic islets and islands 345 km off the coast of northeast Brazil, is an Important Bird Area with two endemic landbirds and nesting colonies of several seabirds. The most recent data concerning avian species in Fernando de Noronha were obtained through a meticulous review of extant literature, searches of citizen science databases, and ad libitum field surveys. In this study, 76 species of birds were recorded, with 20 residents, 22 migrants and 34 vagrants. Most of the vagrant species were found in artificial freshwater reservoirs, proving to be a critical resource. Fernando de Noronha has the highest number of breeding seabird species of any other Brazilian oceanic island, but introduced predators (rats, tegu lizards and cats) have restricted most colonies to the isolated islets. Understanding the use of the archipelago's territory and which areas are most important for these populations is key for implementing efficient conservation strategies.

This is the first study in cycads to measure genetics, demography, and survival of plant populations due to an invasive insect. The armored scale Aulacaspis yasumatsui invaded the island of Rota in 2007 posing a new threat to the native Cycas micronesica population. The pre-invasion genetic structure of the host plant populations revealed considerable genetic variation and restricted gene flow among habitats and identified genetic clusters representing the genetic variation of the species in Rota. Prior to localized A. yasumatsui infestations, 28 permanent plots were established among seven locations in 2008. Data were collected to document survival and demography until 2023. There were 11,254 stems per ha in 2008, 9.2% of which were adult trees. The seedlings rapidly reached 100% mortality, and no seedlings were observed in the plots from 2014 until 2023. There were 149 stems per ha in 2023, 100% of which were adult trees. This invasion behaved similarly to the invasions of other islands, with the native cycad population reaching 98.6% mortality of the entire population and 85.6% mortality of the adult tree population within a 15-year span. Mean stem height was only 30 cm in 2008 because of the majority of the population was seedlings and juveniles. Mean stem height gradually increased with each successive year of data collection due to selective mortality of the small plants, and was 245 cm in 2023. Mean leaf number per adult tree was 83 in 2008, abruptly declined to a low of 8 in 2013, then gradually increased to 20 in 2023. Incidence of the herbivore rapidly increased to a peak in 2011 before stabilizing to about 40% to 50% of the soft organ surfaces. The invasion of this insular cycad population by A. yasumatsui caused selective mortality of the smallest plants, and the population-level mortality was more rapid than the prior invasion of nearby Guam. These combined results provide a genetic baseline and population structure benchmark for future conservation protocols during species recovery efforts. The geographically separated and genetically isolated populations indicate this cycad species remains highly vulnerable to localized extirpations, as the unique alleles from extirpated habitats are at risk of being lost forever.

BackgroundArthropods provide essential ecosystem services, yet multiple lines of evidence indicate widespread declines driven by habitat loss (degradation, fragmentation and reduction), biological invasions and climate change. Oceanic islands are particularly vulnerable to invasive alien species because of their isolation, small area and sensitivity to novel predators, competitors and pathogens. In the Azores, historical land-use change has greatly reduced native forest cover, while long-term monitoring indicates that introduced arthropod diversity is increasing even where total richness appears stable. However, ruderal coastal habitats (i.e. transitional, frequently disturbed environments often dominated by opportunistic exotic plants) remain comparatively under-sampled and may function as early “gateways” for new arthropod introductions. The PRIBES project intends to contribute to "The Regional Strategy for the Management of Terrestrial and Freshwater Exotic and Invasive Species in the Azores" (PRIBES-LIFE-IP- Estratégia regional para o controlo e prevenção de espécies exóticas invasoras - no âmbito do projeto LIFE IP AZORES NATURA, LIFE17 IPE/PT/000010). The PRIBES project addresses this gap by surveying arthropod assemblages associated with vascular plants in disturbed coastal ruderal habitats across multiple Azorean islands (Corvo, Flores, Faial, Pico, Terceira, São Miguel and Santa Maria) using a standardised time-based plant beating protocol, enabling comparisons of richness and colonisation status (endemic, native or exotic) amongst islands and vegetation contexts.New informationThis manuscript provides a standardised, multi-island synthesis of arthropod sampling across seven Azorean islands, encompassing 78 sites sampled with standard methods plus one site with ad hoc samples and 23,547 specimens. It reports 366 taxa, including 247 taxa identified to species/subspecies and 119 not identified morphospecies, delivering an unusually comprehensive archipelago-scale baseline for ruderal and edge-associated assemblages. The substantial unidentified morphospecies fraction, plausibly dominated by as-yet-unrecorded Azorean arrivals despite extensive local expertise, is consistent with documented increases in island exotic arthropod diversity and highlights an identification bottleneck where recent introductions and potential pests accumulate. The study also provides major distributional updates, including 62 new island records and one new record for the Azores, corresponding to the theridiid spider Dipoenamelanogaster (C. L. Koch, 1837). By summarising colonisation status for all identified taxa, we show a strong contribution of introduced taxa (121 of 247 identified taxa) alongside endemic (37) and native non-endemic (72) components, offering a clear quantitative snapshot of assemblage structure relevant to biosecurity and conservation planning. In addition, for 17 taxa, the colonisation status is uncertain. By publishing openly accessible, standardised occurrence records, these data directly support early detection and surveillance prioritisation for emerging introductions and help provide information for management and biosecurity strategies in rapidly changing island landscapes.

Evolutionary radiations on oceanic archipelagos (ROAs) have long served as models for understanding evolutionary and ecological processes underlying species diversification. Yet, diversity patterns emerging from ROAs have received relatively little attention from biogeographers, even though characterizing the effect of key geo-environmental factors on island clade species could be important for unraveling diversification dynamics. In this study, we conducted a comparative analysis using island-specific species richness values for approximately one hundred ROAs across major oceanic archipelagos (mostly Hawaii, Canary Islands, Galápagos and Fiji) and taxa (vascular plants, invertebrates and vertebrates). Our aim was to determine whether (1) ROA species richness patterns scale as a function of key geo-environmental factors including island area, geological age, environmental heterogeneity (elevation and topographic complexity) and inter-island isolation, and (2) whether the magnitude of the effects of these factors varies across archipelagos and taxa. Our results identified elevation as a key driver of ROA species richness patterns on islands, supporting existing theoretical and empirical work that highlighted the central role of environmental heterogeneity in driving diversification on oceanic islands. As importantly, we found that the influence of geo-environmental factors varies across archipelagos and taxa, suggesting that unique archipelagic dynamics and biological traits together shape diversification differently. Our findings emphasize the value of applying biogeographical modeling at the resolution of individual radiations to improve our understanding of evolutionary processes on oceanic archipelagos.

ABSTRACT Within popular discourse, Buddhist conservation efforts are often believed to be motivated by scriptural principles such as loving-kindness, non-violence and interdependent co-arising. In this article, I point out the limitations of focusing on these as the only motivations for caring for animals. Introducing the concept of ‘bio-retribution’, I will describe how on Christmas Island the ireful and vengeful crabs can be seen as posing a danger to those who intentionally or accidentally kill them. To ameliorate the consequences of harming crabs and to support the dead crabs in their rebirths, some of the island’s Buddhists recite the long mantra of Amituofo (Amitābha). In addition to feeling genuine affection for and kinship with the island’s crabs, avoiding bio-retribution is an active motivator in caring for the island’s crabs, in both the mundane and the supramundane realms.

Microplastic pollution represents a relevant environmental issue for the conservation of marine environments. Glitter particles are often a single-use material and are considered an important group of microplastics. These particles are bioavailable and may pose a significant contamination risk to aquatic ecosystems. The present study reports the first record of hexagonal glitter particles ingested by corals from two Brazilian oceanic islands in the Atlantic Ocean, about 1140 km east of the Brazilian coast: Trindade and Martim Vaz. Fragments of Mussismilia hispida and Montastraea cavernosa corals were analyzed for the presence of ingested glitter particles. Hexagonal glitter particles were observed in both species, with abundance reaching up to 304.76 ± 81.27 particles.g−1 of soft tissue for M. cavernosa and 629.63 ± 101.23 particles.g−1 of soft tissue for M. hispida. The average size of hexagonal glitter particles was 28.10 ± 7.17 µm. The polymeric composition was identified as polyethylene terephthalate (PET). Our data highlight the susceptibility of coral species to act as sinks for microplastics, even in remote areas.

ABSTRACT Specimens of the freshwater red algal genus Riverina were discovered in a clear-water river in Mauritius, marking the first record of the genus from an Indian Ocean island. Morphological observations and phylogenetic analyses of chloroplast rbcL and nuclear-based 18S rDNA sequences were used to characterize the collection. While the specimens were morphologically similar to known Riverina species, molecular data placed them within a distinct clade sister to R. tahitiensis and R. angolensis. Significant genetic divergence from Tahitian and Philippine lineages confirms that the Mauritian material represents a distinct evolutionary lineage. Consequently, Riverina vaughanii sp. nov. is formally described. This study expands the known biogeographic range of the genus and highlights the cryptic diversity of freshwater red algae in the western Indian Ocean island.

Anthropogenic stones on a remote oceanic island: formation, transport, and burial in a sea turtle nesting beach.