Search Results (853)

Plastic debris is a pervasive and persistent threat to marine ecosystems. Microplastics (plastics < 5 mm) are increasing in a variety of marine habitats, including open water systems, shorelines, and benthic sediments. It remains unclear how microplastics distribute and accumulate in marine systems and the extent to which this pollutant is accessible to marine taxa. We examined subtidal benthic sediments and beach sediments in critical nearshore habitats for forage fish species—Pacific sand lance (Ammodytes personatus), Pacific herring (Clupea pallasi), and surf smelt (Hypomesus pretiosus)—to quantify microplastic concentrations in the spawning and deep-water habitats of these fish and better understand how microplastics accumulate and distribute in nearshore systems. In the San Juan Islands, we examined an offshore subtidal bedform in a high-flow channel and beach sites of protected and exposed shorelines. We also examined 12 beach sites proximate to urban areas in Puget Sound. Microplastics were found in all samples and at all sample sites. Microfibers were the most abundant, and flakes were present proximate to major shipyards and marinas. Microplastics were significantly elevated in Puget Sound compared to the San Juan Archipelago. Protected beaches had elevated concentrations relative to exposed beaches and subtidal sediments. Microplastics were in higher concentrations in sand and fine-grain sediments, poorly sorted sediments, and artificial sediments. Microplastics were also elevated at sites confirmed as spawning habitats for forage fish. The model results indicate that both current speed and proximate urban populations influence nearshore microplastic concentrations. Our research provides new insights into how microplastics are distributed, deposited, and retained in marine sediments and shorelines, as well as insight into potential exposure in benthic, demersal, and shoreline habitats. Further analyses are required to examine the relative influence of urban populations and shipping lanes and the effects of physical processes such as wave exposure, tidal currents, and shoreline geometry. Full article

Accurate prediction of drifting trajectories is essential for improving the operational efficiency of maritime search and rescue (SAR), particularly within the complex geomorphological settings of island and reef regions, such as those in the South China Sea. This study investigates the drift characteristics of life rafts under varying loading conditions across both open-sea and island–reef regions. Comprehensive field experiments were conducted over 15 days in the waters around the Wanshan Archipelago, using advanced instruments to collect wind, current, and drift trajectory data. Based on these observations, two models—the AP98 leeway model and a BP neural network model—were developed and validated. The results show that the AP98 model performs better in open-sea conditions, whereas the BP neural network provides more accurate predictions in island and reef areas with complex environmental factors. A Monte Carlo simulation was also integrated to enhance the robustness of drift area predictions. These findings offer valuable insights into life raft drift behavior in complex marine environments and provide technical support for improving SAR operations in island–reef regions. Full article

Elasmobranch species are considered a global conservation priority due to their susceptibility to fishing pressure. In the Madeira Archipelago, Northeastern Atlantic, most elasmobranch species are caught as bycatch in artisanal drifting longline fishery targeting scabbardfishes. All commercial elasmobranch landings carried out in this archipelago over three decades (1990–2020) were analysed, aiming to provide a reliable overview of Madeira’s elasmobranch fisheries and their evolution. A total of 2316 tonnes of elasmobranchs were landed during the study period, corresponding to approximately EUR 2.1 million in first-sale value. The most representative period occurred from 2003 to 2013, corresponding to 75.21% of the total elasmobranch landings. A general pattern of supply and demand was evident, with mean price values typically showing an inverse trend to landed tonnage. At the species level, Centrophorus squamosus appears as the dominant species, representing about 89% of the total elasmobranch species landed, followed by Prionace glauca, with approximately 3%. The high dominance of C. squamosus in the scabbardfish fishery raises significant ecological and management concerns, as this deep-water shark species is known for its vulnerability to overexploitation. Management measures currently in place need to be updated and ought to be based on studies on the type and size of hooks for each fishery, to ultimately infer about species-specific survival rates, as well as the fishing gears’ soak time. Moreover, studies on the enhancement of food supply through fisheries discards are still missing, even though it is highly likely that this input may alter the dynamics of marine food webs. Full article

This data descriptor presents the HF radar and drifter datasets, along with the methods used to process and apply them in a previously published study on the validation of surface current measurements in a region characterized by highly variable coastal dynamics. The data were collected in the framework of a large-scale Lagrangian experiment, which included extensive drifter deployment and the generation of virtual trajectories based on HF radar-derived flow fields. Both Eulerian and Lagrangian approaches were used to assess radar performance through correlation and RMSE metrics, with additional refinement achieved via Kriging interpolation. The validation results, published in Remote Sensing, demonstrated good agreement between HF radar and drifter observations, particularly when quality control parameters were optimized. The datasets and associated methodologies described here support ongoing efforts to enhance HF radar tuning strategies and improve surface current monitoring in complex marine environments. Full article

Mapping marine habitats is fundamental for biodiversity conservation and ecosystem-based management in oceanic regions under increasing anthropogenic and climatic pressures. In the context of global initiatives—such as marine protected area expansion and international agreements—habitat mapping has become mandatory for regional and global conservation policies. It provides spatial data to delineate essential habitats, support connectivity analyses, and assess pressures, enabling ecosystem-based marine spatial planning aligned with EU directives (2008/56/EC; 2014/89/EU). Beyond biodiversity, macrophytes, rhodolith beds, and coral reefs deliver key ecosystem services—carbon sequestration, coastal protection, nursery functions, and fisheries support—essential to local socioeconomies. This systematic review (PRISMA guidelines) examined 69 peer-reviewed studies across Central-Eastern Atlantic archipelagos (Macaronesia: the Azores, Madeira, the Canaries, and Cabo Verde) and the Mid-Atlantic Ridge. We identified knowledge gaps, methodological trends, and key challenges, emphasizing the integration of cartographic, ecological, and technological approaches. Although methodologies diversified over time, the lack of survey standardization, limited ground truthing, and heterogeneous datasets constrained the production of high-resolution bionomic maps. Regional disparities persist in technology access and habitat coverage. The Azores showed the highest species richness (393), dominated by acoustic mapping in corals. Madeira was most advanced in the remote mapping of rhodoliths; the Canaries focused on shallow macrophytes with direct mapping; and Cabo Verde remains underrepresented. Harmonized protocols and regional cooperation are needed to improve data interoperability and predictive modeling. Full article

Understanding and promoting guest satisfaction is central to the economic sustainability of the hospitality industry. Satisfaction influences consumers’ booking intentions, hotel choice, loyalty, and the reputation and performance of accommodation establishments. Thus, accurate decision making by hotel managers relies on trustworthy and easily accessible information on the variables that affect guest satisfaction. Nowadays, this information is available through reviews and ratings provided by online platforms, such as TripAdvisor. Indeed, much research into guest satisfaction uses TripAdvisor reviews. However, this study aims to analyse guest satisfaction using only TripAdvisor ratings. These ratings can be more succinct and tractable indicators than reviews. A sample of 118 hotels in Cape Verde and the Azores, two archipelagos belonging to Macaronesia, and a descriptive, predictive, and discriminant methodology are employed for this purpose. Four main results are obtained. First, the rated items on TripAdvisor are consistent with the scientific literature on this topic. Second, TripAdvisor ratings are valid and reliable. Third, TripAdvisor ratings can predict guest satisfaction based on the perceived quality of hotel services. Fourth, there are significant differences in ratings depending on the tourism destination chosen. These results are of interest to researchers, tourists, as well as hotel, destination, and platform managers. Full article

This study compiles and updates data to construct the phosphorus budget of the Archipelago Sea (northern Baltic Sea, Europe), with a particular focus on estimating phosphorus pools associated with fish populations. Biomass data and species-specific phosphorus content were utilized, and a bioenergetic modeling approach was applied to Baltic herring (Clupea harengus membras) and European perch (Perca fluviatilis) to estimate species-specific food consumption and nutrient excretion. Between 2001 and 2024, average total phosphorus concentrations were 28% higher than during the baseline period of 1983–1989. From 1998 to 2023, the annual average fish catch in the Archipelago Sea was 15,516.5 tons (16.3 kg/ha), with 73.1% consisting of commercially harvested herring. Other abundant catch species included, for example, pikeperch (Sander lucioperca), northern pike (Esox lucius), and European smelt (Osmerus eperlanus). On average, the annual catch contained 83.4 tons of phosphorus. Fishing may have annually removed an amount of phosphorus equivalent to approximately 0.6% of the total phosphorus pool in the water column and surface sediment, or 1.4% of the estimated total phosphorus load to the Archipelago Sea. The contribution of fish to phosphorus turnover is minor, as nutrient recycling is dominated by plankton. Planktivorous fish and their prey recycle nutrients already present in the water column and are therefore not the primary drivers of eutrophication. Full article

There are very few data linking recent climatic changes to changes in biological communities in the Russian Arctic, and no palaeoecological data are available from the Novaya Zemlya archipelago (NZ). We studied chironomid, cladoceran, and diatom communities from a 165-year-old sediment core from a lake on Southern Island, NZ. Sixteen diatom and four cladoceran species new to NZ were found in the lake. Significant changes occurred in biological communities; species turnover was highest for diatoms (2.533 SD), followed by chironomids (1.781 SD) and cladocerans (0.614 SD). Biological communities showed a correlation with meteorologically recorded climate parameters. For chironomids, the strongest relationships were found for T_June, T_July, and T_ann. Both planktonic proxies, diatoms, and cladocerans showed a relationship with summer and annual air temperature and precipitation. The largest shifts in communities can be linked to recent climatic events, including the onset of steady warming following the variable conditions at the end of the LIA (ca. 1905), the cooling associated with the highest precipitation on record between 1950 and 1970, and, probably, the anthropogenic influence specific to Novaya Zemlya at this time. The new data provide a valuable basis for future ecological studies in one of the least explored and remote Arctic regions. Full article

Background/Objectives: Ants are one of the most abundant animal groups on the planet and have a considerable impact on ecosystems. In the Cabo Verde Archipelago, the study of invertebrates is very scarce and ants are no exception. Methods: In this work we focus on the taxonomic analysis of formicids and study their distribution and the possible presence of invasive species in the Cabo Verde Islands. In addition, the diversity of Cabo Verde ants is compared with that of the closest African coastal countries, Senegal and Mauritania, to study a possible colonization of African ants into the archipelago. For this, we use two molecular markers, cytochrome oxidase I and the wingless gene, to perform phylogenetic analyses and haplotype networks that facilitate identification. Results: Nine taxa were identified, five invasive species, Paratrechina longicornis, Pheidole megacephala, Trichomyrmex destructor, Brachyponera sennaarensis, and Solenopsis globularia, one endemic Monomorium subopacum and three unidentified species of native genera, Monomorium sp., Lepisiota sp. Camponotus sp. Conclusions: Molecular network patterns as well as phylogenetic analyses suggest that ants are widespread throughout the archipelago, a likely consequence of human introductions. Full article

A study was carried out with a representative data set of volcanic lakes from the Azores archipelago. A total of 672 samples were collected during four field surveys conducted over the year and along the depth. Following water sampling, temperature, pH, and EC were measured, the dissolved CO₂ and alkalinity were determined by titration, and aliquots were taken to perform analysis of major, minor and trace elements, as well as ¹⁸O/¹⁶O, ²H/¹H and ⁸⁷Sr/⁸⁶Sr isotopic ratios. Waters are of meteoric origin and from the Na-HCO₃ to Na-Cl types. The ⁸⁷Sr/⁸⁶Sr ranges between 0.709194 and 0.704294, and most of the lakes depict less radiogenic values than seawater, suggesting a potential contribution from rock dissolution. Along the reciprocal of the Sr vs. ⁸⁷Sr/⁸⁶Sr plot, most samples suggest a linear trend between rock values and rainwater. Samples display considerable variability in the ∑REE, ranging from 0.83 µg L⁻¹ to 13.54 µg L⁻¹, and when chondrite normalized, depict a negative slope, showing an enrichment in light REEs compared to heavy REEs. This pattern is consistent with the one from Azores rocks and bottom sediments from some lakes, and most lakes depict Eu anomalies, resulting from interaction between water and sediments or from incongruent mineral dissolution. Full article

Background/Objectives: Periploca chevalieri Browicz (Apocynaceae), an endemic species of the Cabo Verde archipelago, is commonly used in traditional medicine for the treatment of diabetes. The aim of this study was to characterize the chemical profiles of the aqueous and hydroethanolic (70%) extracts of the P. chevalieri dried aerial parts (PcAE and PcEE) and evaluate their potential to modulate postprandial glycemia and inhibit key carbohydrate-hydrolyzing enzymes. Methods: The chemical characterization was performed by LC/UV-DAD-ESI/MS/MS. An in vivo evaluation of postprandial glycemia modulation was conducted on healthy CD1 mice submitted to an oral sucrose tolerance test. In vitro enzymatic inhibition was performed for the α-amylase, α-glucosidase, and DPP4 enzymes. Additionally, antioxidant and antiglycation activities were also assessed. Results: Phenolic acid derivatives, flavanols, proanthocyanidins, and flavonols were the major classes of secondary metabolites identified. PcEE at 170 mg/kg of body weight significantly (p < 0.05) reduced the postprandial glycemia peak in CD1 mice submitted to sucrose overload. Regarding the enzymatic inhibition, both extracts showed concentration-dependent inhibitory potential against the α-amylase, α-glucosidase, and DPP4 enzymes. Both extracts inhibited α-glucosidase more effectively than acarbose. Conclusions: The obtained results supports the traditional use of P. chevalieri and suggest the potential for further pharmacological investigation. Full article

Coastal erosion poses a significant threat to small tropical island regions, where coastal tourism and infrastructure play vital economic roles. However, the processes affecting tropical beaches, particularly in Central America, remain underexplored due to a lack of data on waves and atmospheric conditions. We propose a novel approach that utilises low-cost smartphone and satellite imagery to characterise beach ecosystems, where typically expensive and technologically intensive monitoring strategies are impractical and background data are scarce. As a test of its performance under real conditions, we apply this approach to four contrasting beaches in the low-lying islands of the Bocas del Toro Archipelago, Panama. We employ Earth Observation data and field-based monitoring to enhance understanding of beach erosion. Optical flow tracking velocimetry (OFTV) is applied to smartphone camera footage to provide a quantitative metric of wave characteristics during the high wave energy season. These data are combined with satellite-derived shoreline change data and additional field data on beach profiles and grain size. The results reveal distinct patterns of accretion and erosion across the study sites determined by wave climate, beach morphology, and grain size. Accreting beaches are generally characterised by longer wave periods, more consistent wave velocities, and finer, positively skewed sediments indicative of swell-dominated conditions and dissipative beach profiles. Conversely, more erosive sites are associated with shorter wave periods, more variable wave velocities, coarser and better-sorted sediments, and a shorter, steeper beach profile. Seasonal erosion during the high-energy wave season (January–April) and subsequent recovery were observed at most sites. This work demonstrates how foundational data for evidence-based coastal management can be generated in remote locations that lack essential baseline data. Full article

This study investigates the seasonal and floral phenology, breeding strategies, and floral morphology of Azorina vidalii, an Azorean endemic Campanulaceae with hermaphroditic, protandrous flowers, dichogamy and secondary pollen presentation. Seasonal phenology was recorded in four field populations and floral phenology in a garden population. Reproductive strategies were assessed via controlled hand pollinations in one field population. Floral morphometrics were analysed using 23 floral and five pollen traits from 121 flowers across fourteen populations throughout the Azores archipelago. Non-parametric and parametric tests, discriminant analysis, and reproductive indices were used to infer answers to this study’s goals. Results showed that temperature and humidity influenced vegetative and reproductive phenophases. The male phase was shorter than the female, likely due to pollen dynamics, and some functional overlap suggested incomplete dichogamy. Geographic variation in floral traits indicated morphological differentiation across subarchipelagos, presumably linked to environmental factors or isolation. Reproductive indices suggested a mixed mating system, partial self–incompatibility and signs of inbreeding depression. Fertilisation was absent without pollinators, and spontaneous selfing was excluded due to an absence of pollen–pistil contact during stigma retraction. These findings contribute to understanding the reproductive biology and morphologic variation in A. vidalii. The implications of these findings for the conservation of this insular plant are discussed. Full article

Heartworm disease (Dirofilaria immitis) is an important zoonotic infection of major clinical importance in dogs widespread, and transmitted by culicid vectors. Although D. immitis mostly affects dogs with an overall low incidence, some islands of the Atlantic archipelagos such as the island of Gran Canaria (Canary Islands, Spain) had one of the highest historical prevalence/seroprevalence values in dogs, cats and humans. Molecular tools allow us to perform species identification diagnosis, phylogeographic and population genetics analysis that can provide key information about the factors making the disease still a threat (uncover untreated range of hosts, putative origin, etc.). In this study, we have optimized primers to amplify mitochondrial (COI, 12S) and nuclear (ITS) molecular markers from adult D. immitis worms. The genetic diversity and structure of D. immitis at the global level is limited, especially when compared with results obtained for other species of the same genus, such as D. repens. New minor haplotypes in the mitochondrial COI marker have been identified from adult D. immitis worms from infected dogs from the hyperendemic island of Gran Canaria, suggesting that the disease may have originated locally or may have been introduced from the mainland in historical times and evolved in isolation. To obtain a more complete understanding of its evolutionary history, structure and genomic diversity, comparative studies using next-generation sequencing data from endemic areas are needed, which will help in the long term to implement monitoring and control measures in a given area and to better understand its global phylogeographic history. Full article

This study presented a comprehensive physical–statistical analysis of atmospheric particulate matter (PM₁₀ and PM_2.5) and trace gases (SO₂ and O₃) over Faial Island in the Azores archipelago during 2024. We collected real-time data at the Espalhafatos rural background station, covering 35,137 observations per pollutant, with 15 min intervals. Descriptive statistics, probability distribution fitting (Normal, Lognormal, Weibull, Gamma), and correlation analyses were employed to characterize pollutant dynamics and identify extreme pollution episodes. The results revealed that PM_2.5 (fine particles) concentrations are best modeled by a Lognormal distribution, while PM₁₀ concentrations fit a Gamma distribution, highlighting the presence of heavy-tailed, positively skewed behavior in both cases. Seasonal and episodic variability was significant, with multiple Saharan dust transport events contributing to PM exceedances, particularly during winter and spring months. These events, confirmed by CAMS and SKIRON dust dispersion models, affected not only southern Europe but also the Northeast Atlantic, including the Azores region. Weak to moderate correlations were observed between PM concentrations and meteorological variables, indicating complex interactions influenced by atmospheric stability and long-range transport processes. Linear regression analyses between SO₂ and O₃, and between SO₂ and PM_2.5, showed statistically significant but low-explanatory relationships, suggesting that other meteorological and chemical factors play a dominant role. This result highlights the importance of developing air quality policies that address both local emissions and long-range transport phenomena. They support the implementation of early warning systems and health risk assessments based on probabilistic modeling of particulate matter concentrations, even in remote Atlantic locations such as the Azores. Full article