Atlantic Islands Research Articles

La exploración de los hidrocarburos en el caso de las islas Malvinas de 1995 a 2022

This paper aims to analyze the hydrocarbon exploration process in the Malvinas Islands carried out by the United Kingdom from 1995 to 2022. In relation to this, the question of the Malvinas Islands refers to a dispute between the Argentine and British governments over sovereignty over the Malvinas Islands and islands of the South Atlantic, the surrounding marine spaces, which also includes oil and gas. In this sense, these resources hosted on the islands’ submarine shelf were a long-standing focus of interest. In the 1990s, the British government authorized the arrival of transnational companies to carry out exploration activities and possible exploitation in an area that is still under international dispute. In this context, the Argentine State recognized these insular and maritime areas as an integral part of its national territory and, consequently, rejected the presence of these companies and declared their activities illegal.

Evidence for a floristically diverse rainforest on the Falkland archipelago in the remote South Atlantic during the mid- to late Cenozoic

Abstract We report the discovery of an ancient forest bed near Stanley, on the Falkland Islands, the second such ancient deposit identified on the South Atlantic island archipelago that is today marked by the absence of native tree species. Fossil pollen, spores and wood fragments preserved in this buried deposit at Tussac House show that the source vegetation was characterized by a floristically diverse rainforest dominated by Nothofagus-Podocarpaceae communities, similar to cool temperate Nothofagus forests/woodlands and Magellanic evergreen Nothofagus rainforests. The age limit of the deposit is inferred from the stratigraphic distribution of fossil pollen species transported by wind, birds or ocean currents from southern Patagonia, as well as similar vegetation types observed across the broader region. The deposit is suggested to be between Late Oligocene and Early Miocene, making it slightly older than the previously analysed Neogene West Point Island forest bed (200 km west of Tussac House). The combined evidence adds to our current knowledge of the role of climate change and transoceanic dispersal of plant propagules in shaping high-latitude ecosystems in the Southern Hemisphere during the late Palaeogene and Neogene.

Seasonal Patterns, Inter‐Annual Variability, and Long‐Term Trends of Mean Sea Level Along the Western Iberian Coast and the North Atlantic Islands

AbstractSea level rise is challenging for coastal communities and land management decision makers. Understanding the patterns of regional variations at different temporal and spatial scales is key to implement adaptation plans that mitigate the local impacts of sea level rise. In this study, in situ observations from 14 tide gauges were complemented with satellite altimetry data to assess seasonality, multidecadal variability and long‐term trends in mean sea level around the Western Iberian Coast (WIC) and the Portuguese archipelagos (Azores and Madeira). Results show varying spatial seasonal patterns between regions, with minimum (maximum) sea level observed in April (September) at the islands and minimum (maximum) observed in July (November) at the WIC. The influence of coastal upwelling on the seasonal mean sea level variations was detected over mainland. Although the influence of atmospheric patterns was observed on sea level inter‐annual variability, the Atlantic Multidecadal Oscillation (AMO) showed a greater correlation with the sea level inter‐decadal patterns. Finally, the trend analysis confirmed widespread sea level rise along the mainland and around the islands, which has intensified in recent decades. The regions of La Coruña and Cascais showed trends that were similar to the global average sea level rise since 1993, but the mainland regional average pointed to lower rates of rise (2.00 ± 0.06 mm/year). This work reinforces the need for long‐term monitoring networks of sea level, ensuring the vertical stability of instruments and platforms. The implementation of regional adaptation plans to sea level rise is deeply dependent on high quality information.

The Saga of Lohodann: Making Sense of an Annobonese Folktale Rooted in Carolingian Drama

The essay analyzes the saga of Lohodann in relation to the idiosyncratic cultural and religious history of the African Atlantic island of Annobón. It does so by placing the history of the island in the context of the Portuguese expansion in Africa during the early modern era, and studies the folktale in connection to the dissemination of Iberian cultural elements in the region. It pays special attention to the role of confraternities, in the context of which the population of Annobón reinvented and reimagined Iberian culture from an African perspective.

First assessment of persistent organic pollutants and halogenated natural compounds in an omnivorous resident coral-reef fish species, black triggerfish, Melichthys niger, from an Atlantic oceanic island, Brazil

Studies on the occurrence of POPs and other persistent compounds in pristine areas are extremely valuable, as they offer insights on the long-range transportation of POPs and the occurrence of natural compound producers' areas. In this regard, this study aimed to report data of both anthropogenic (polychlorinated biphenyls, PCBs, and polybrominated diphenyl ethers, PBDEs) and natural (methoxylated PBDEs, MeO-BDEs) compounds in tissues of the black triggerfish, Melichthys niger (Tetraodontiformes, Balistidae), specimens (n = 30) sampled in 2018 during a scientific expedition conducted at Trindade Island. Concentrations of ∑28PCBs ranged from 73 to 1052 ng g−1 lw in liver, 334 to 1981 ng g−1 lw in gonads, and 20 to 257 ng g−1 lw in muscle, with the predominance of PCB-180 in liver and PCB-52 in gonad and muscle. Concentrations of ∑7PBDEs ranged from <LOD to 1.8 ng g−1 lw in liver, <LOD to 14 ng g−1 lw in muscle, and they were < LOD in gonads. The BDE-47 was the most representative congener detected in liver and muscle. Mean concentrations of ∑8MeO-BDEs were 270 ng g−1 lw, 442 ng g−1 lw, and 70 ng g−1 lw in liver, gonad, and muscle, respectively. The 2-MeO-BDE-68 was the most representative congener among MeO-BDEs. The mobilization of lower chlorinated PCBs from liver to other tissues, with possible retention of higher chlorinated PCBs in liver, can be a factor of concern considering the chronic exposure of those fish. PBDEs and MeO-BDEs in fish from remote environments were reported in a low number of studies worldwide. Considering that remote sites face environmental pollution either directly by anthropogenic influence or by long-range transportation, more studies on the occurrence of persistent compounds in these environments are paramount, and it is fundamental to understand the dispersion and accumulation of POPs.

The Time-Space Regimes of Human Mobility in the North Atlantic Island Spaces (Iceland, Azores, Madeira, the Canary Islands, and Cape Verde)

Throughout history the North Atlantic archipelagos have projected themselves outwards thanks to travel and the innate capacity of their inhabitants to relate to other peoples. This research aims to reveal their nodal character on the stage of global mobility, using a detailed statistical analysis of their migration trends since the 1960s. To this end, it is necessary to recognise the rhythms of the migration transition and its parallelism with the socio-economic development of the island spaces themselves. In addition, common features can be identified in their recent migration patterns in which a great diversification of origins and destinations predominates, as well as a multiplicity of motivations. With this aim, migration in these archipelagos is interpreted from a temporal and spatial perspective, redefining the historical concept of “Atlanticity,” and allowing to identify the strategic position they play in the geography of human mobility in times of global capitalism.

Optimal Arrangements of Renewable Energy Systems for Promoting the Decarbonization of Desalination Plants

In this research, a renewable energy hybrid system (PV-Wind) is modeled to compare different design options based on their economic and technical features. The energy requirements of a Reversible Osmosis desalination plant located on the island of Tenerife with a water production capacity of up to 20,000 m3/day was considered. The system is connected to the electricity grid. The HOMER software, version 2.75 was used to produce optimum strategies for renewable energy. The assumptions input into the model were: the technical specifications of the devices, electricity demand of the desalination plant, as well as the solar radiation and the wind speed potentials. Numerous arrangements were considered by the software, version 2.75. The optimal results were obtained based on the use of renewable energy. The data used in the study were recorded in Tenerife in the Canary Islands. The experience of this research could be transferred to other Atlantic islands with similar renewable energy sources (specifically the wind) and water scarce conditions.

First insights into the spatial behaviour of Octopus vulgaris in the wild using acoustic telemetry

Octopuses are amongst the most fascinating animals in our oceans; however, while their intricate behaviours are often studied in laboratory settings, basic aspects of their movement ecology remain unstudied in the wild. Focusing on the socio-economically important common octopus (Octopus vulgaris), this study employs, for the first time, acoustic tracking techniques to address knowledge gaps regarding the species spatial ecology within a marine protected area. A total of 24 wild O. vulgaris (13 males, 11 females) were tagged in 2022 in the National Park Maritime-Terrestrial of the Atlantic Islands of Galicia, Spain. Acoustic transmitters were externally attached to the third arm, after testing other body parts (mantle cavity). Males were on average detected on 10 times more occasions than females (49 days in males and five in females). The average activity space in the study area was large in comparison to that determined in similar studies, with 0.16 km2. Activity space between males and females as well as day and night were comparable. Tagged octopuses displayed a crepuscular activity pattern. The location of dens could be established for 15 out of 24 individuals, from which octopuses were observed to undertake regular daytime excursions. Several individuals were also found to occupy more than one den and/or switch their main dens throughout the study duration. First implications and benefits of this approach are discussed.

The contraction of freshwater lenses in barrier island: A combined geophysical and numerical analysis

Coastal aquifers, vital for supplying freshwater to over one billion people worldwide, often face saltwater intrusion, with barrier island aquifers playing a crucial role in this coastal system. Despite the proliferation of studies exploring the impacts of sea-level rise, storm surges, and over-pumping, the effect of droughts on barrier island aquifers salinization remains largely under-investigated. This lack of attention is particularly concerning given the heightened vulnerability of barrier island aquifers; most ultimately rely solely on aerial recharge compared to continental coastal aquifers. An in-depth understanding of recharge and salinization processes is important for sustainably managing these islands' marginal freshwater resources, especially considering climate change impacts. This study presents an evaluation approach for the response of a freshwater lens (FWL) to drought conditions, incorporating in-situ observations, geophysical measurements, and numerical modeling. The study examines the response of a shallow unconfined aquifer on an Atlantic coast barrier island to the 2020 Northeast extreme hydrological drought. It encompasses a density-driven flow model informed by time-lapse electrical resistivity imaging and in-situ measurements, including groundwater head and salinity collected from monitoring wells. Results from our approach indicate that FWL volume is reduced by 11% during the drought, but it returns to its previous volume over the following spring season, indicating that the net volume of the FWL remains unchanged on an annual scale. The mean groundwater residence time on the island is approximately a year, indicating that the barrier island aquifer is a hydrodynamically active coastal zone. These findings highlight the vulnerability and resilience of shallow unconfined barrier island aquifers to droughts and climate change.

Process evaluation of implementation of the early stages of a whole systems approach to obesity in a small Island.

The small Atlantic island of St Helena is a United Kingdom Overseas Territory (UKOT) with a high prevalence of childhood obesity (over a quarter of 4-5 and 10-11 year olds) and, anecdotally, adulthood obesity and its associated health detriments. St Helena have taken a whole systems approach to obesity (WSAO) to address the issue. A WSAO recognises the factors that impact obesity as a complex system and requires a 'health in all policies' approach. UK academic and public health technical support was provided to the local St Helena delivery team. This process evaluation sought to explore the early stages of the WSAO implementation and implications for the transferability of the approach to other small island developing states and UKOT. Data was collected via eight semi-structured interviews, paper based and online surveys, and document analysis. Thematic analysis was used to analyse the data. The analysis identified three factors which aided the first phase of WSAO implementation: (1) senior leaders support for the approach; (2) the academic support provided to establish and develop the approach; and (3) effective adaptation of UK Government resources to suit the local context. Key challenges of early implementation included: maintaining and broadening stakeholder engagement; limited local workforce capacity and baseline knowledge related to obesity and systems thinking; and limited capacity for support from the UK-based academic team due to contract terms and COVID-19 restrictions. Early stages of implementation of a WSAO in a UKOT can be successful when using UK's resources as a guide and adapting them to a small island context. All participants recommended other small islands adopt this approach. Continued senior support, dedicated leadership, and comprehensive community engagement is needed to progress implementation and provide the foundation for long-term impact. Small island developing states considering adopting a WSAO should consider political will, senior level buy-in and support, funding, and local workforce knowledge and capacity to enable the best chances of successful and sustainable implementation.

Phylogenetic placement of Carex dianae Steud., a sedge endemic to the South Atlantic island of St. Helena

Carex dianae Steud. is an endemic sedge of St. Helena, an isolated island in the South Atlantic. Our study provides the first molecular sequence data for this taxon. We generated sequence data for plastid matK and trnK regions and nuclear internal transcribed spacer and external transcribed spacer regions to determine the placement of C. dianae in the broader Carex phylogeny. The placement of C. dianae falls within Carex sect. Spirostachyae Drejer, and it is sister to a clade including Carex clavata Thunb., Carex aethiopica Schkuhr (both from the Cape region of S. Africa), and Carex gunniana Boott (southern Australia). The existence of three divergent nucleotype groups and two plastotypes is revealed from genetic variation within C. dianae. The results suggest that the ancestor of C. dianae likely originated in the Cape region of South Africa, followed by transoceanic dispersal to St. Helena estimated at 4.4–4.9 million years ago, likely by a bird vector. The most divergent population is that on an isolated hill known as “The Barn”, which may represent a distinct taxon. The existence of highly structured molecular variation within an island only 16 km long is discussed.

The digital climate atlas of the Canary Islands: A tool to improve knowledge of climate and temperature and precipitation trends in the Atlantic islands

This paper presents the Interactive Digital Climate Atlas of the Canary Islands, a web portal based on geographic information systems for the dissemination of climate information. It provides citizens and public and private administrations with high spatial resolution maps (100 m) of different climate variables such as temperature, rainfall, relative humidity, cloudiness frequency and wind velocity. Also available are Köppen climate classification maps and decadal trends of temperature and precipitation in a context of climate change. This spatial resolution is suitable for the detailed climatic description of small and orographically complex islands. For this purpose, climate series from databases of different public institutions as well as data from remote sensing and reanalysis systems were employed. A statistical process involving data filtering and the detection and correction of inhomogeneous segments was carried out as a preparatory step. Then, a spatial interpolation model was developed using a multiple linear regression method for the generation of the high spatial resolution climate cartography. The results are annual and monthly maps of the climate variables in Canary Islands at 100 m spatial resolution and with different time periods depending on the availability of data on the different variables, but in most cases between 1991 and 2020. Following the European Directive INSPIRE (Directive 2007/2/CE, Infrastructure for Spatial Information in Europe), both map visualisation and downloading in GeoTIFF and NetCDF format are permitted, as well as consultation of the data and metadata of the climatic series used.

Mangrove development on a remote volcanic island in the South Atlantic

Sueste Bay, in the Fernando de Noronha archipelago (FNA), contains the only mangrove area among the oceanic islands of the South Atlantic. This work aims to reconstruct this mangrove's evolution during the Holocene based on a morphostratigraphic study integrated with palynological and multi-elemental geochemical data, temporally calibrated with radiocarbon dating. The data obtained indicated that, around 8000 to 7000 cal yr BP, well-developed Rhizophora and Laguncularia mangroves established over altered rocks of the Quixaba (phonolites, lamprophyres, basanites, trachyandesites and basalts) and Remédios (basanites, melilite and melanophelinites) Formation, under rising relative sea level, about 2 to 3 m below present. This period was the last record of Rhizophora in the FNA. From 6000 to 3600 cal yr BP, the lagoon system was eroded and significantly retrograded, under rising RSL during at least part of time, leaving clay pebbles scattered in the lower/upper shoreface deposit as the only record of its reworking. This process limited mud/mixed flats near the mouth of the Maceió River. Under a relative stability of RSL from 3600 cal yr BP to the present, a progradation of coastal facies, including beach/foredunes ridges, occurred and allowed the development of the modern lagoon system over swales between aeolian sand ridges. Mangroves were only observed during modern times but in environmental conditions very different from those of the previous occurrence. Indeed, Laguncularia coexists with several invasive plants within the narrow mixed flats associated with a small and almost filled tidal creek, whose siltation may be a product of the artificial damming of the Maceió River to supply public water to the archipelago. This study highlights the complex interactions between natural processes, sea-level changes, and human activities in shaping the coastal evolution of the Fernando de Noronha archipelago over the Holocene.

The German naval strategy for the Atlantic islands between 1940 and 1943

Although the strategic value of the Spanish and Portuguese Atlantic islands for the Third Reich during the Second World War has been the subject of several studies, certain issues remain unknown. One is the link between the strategic re-evaluation of these islands and Spain and Portugal's neutrality. The other is the role of the different Atlantic archipelagos in the German strategy after 1940. To respond to these questions, the author consulted primary sources in the Bundesarchiv-Militärarchiv and other archives elsewhere, as well as the most relevant bibliographical references. Worth highlighting among the conclusions is that the Spanish policy of non-belligerence significantly influenced German interests concerning the Atlantic islands during both the summer and autumn of 1940, as well as in later periods during the conflict.

Distribution patterns of meiofauna and free-living nematodes in beaches of a remote tropical South Atlantic Island (Trindade, Brazil)

Distribution patterns of meiofauna and free-living nematodes in beaches of a remote tropical South Atlantic Island (Trindade, Brazil)

Original plant diversity and ecosystems of a small, remote oceanic island (Corvo, Azores): Implications for biodiversity conservation

Remote islands harbour many endemic species and unique ecosystems. They are also some of the world's most human-impacted systems. It is essential to understand how island species and ecosystems behaved prior to major anthropogenic disruption as a basis for their conservation. This research aims to reconstruct the original, pre-colonial biodiversity of a remote oceanic island to understand the scale of past extinctions, vegetation changes and biodiversity knowledge gaps.We studied fossil remains from the North Atlantic island of Corvo (Azores), including pollen, charcoal, plant macrofossils, diatoms and geochemistry of wetland sediments from the central crater of the island, Caldeirão. A comprehensive list of current vascular plant species was compiled, along with a translation table comparing fossilized pollen to plant species and a framework for identifying extinctions and misclassifications.Pollen and macrofossils provide evidence for eight local extinctions from the island's flora and show that four species listed as ‘introduced’ are native. Up to 23 % of the pollen taxa represent extinct/misclassified species. Corvo's past environment was dynamic, shifting from glacial-era open vegetation to various Holocene forest communities, then almost completely deforested by fires, erosion and grazing following Portuguese colonisation. Historical human impacts explain high ecological turnover, several unrecorded extinctions and the present-day abundance of vegetation types like Sphagnum blanket mire.We use Corvo as a case study on how fossil inventories can address the Wallacean and Hookerian biodiversity knowledge gaps on remote islands. Accurate baselines allow stakeholders to make informed conservation decisions using limited financial and human resources, particularly on islands where profound anthropogenic disruption occurred before comprehensive ecological research.

Quantification of the fishing effort of the artisanal fleet in the Maritime-Terrestrial National Park of the Atlantic Islands of Galicia in the absence of vessel monitoring system

The fishing effort in the marine area of the four archipelagos of the Maritime-Terrestrial National Park of the Atlantic Islands of Galicia (PNMTIAG) is estimated. In the absence of vessel monitoring systems (VMS), a stratified quantitative sampling programme of passive gears deployed and of vessels fishing, in the case of non-passive gears, was used. This programme allowed to quantify the fleet and the fishing effort of each gear, to identify the fishing areas, to obtain a list of the usual vessels in each archipelago and the characteristics of a standard vessel for each of them. The fishing fleet in the park was estimated between 283 and 317 (± 81.5) artisanal fishing vessels working at least once a year with a fishing effort density around 5–26 vessels/km². This effort density was higher than in different MPAs in the western Mediterranean area. However, the density of fishing effort in terms of gears/km² was comparable to some of these same MPAs since the fleet spreads its effort over other fishing areas. The creation of fishing restricted areas inside the National Park could lead to an increase in fishing effort in its waters. The vessels working in the archipelagos of Ons and Cíes are slightly larger than those in Sálvora and the latter larger than those in Cortegada. Around 427 crew members work in this fleet have been estimated considering only vessels using passive fishing gears. Also, these results showed that the methodology used may be sufficient but is not adequate to establish a systematic monitoring of all fishing activity. The implementation of VMS, although not compulsory for small-scale fishing vessels, is essential for the best possible management of fishing activity, especially in areas of special protection such as the one in this study.

Hyperdominance and habitat composition drive reef fish foraging at Atlantic oceanic islands

Spatial and temporal patterns of benthic community structure play a crucial role in shaping reef habitats and have a direct impact on fish foraging dynamics, alongside density-dependent effects on the whole community. At isolated oceanic islands, the relatively low fish species richness often leads to the hyperdominance of a few species and a general reduced trophic redundancy. However, the influence of benthic habitat features and hyperdominant species on foraging selection at oceanic islands has been largely overlooked. We used remote underwater videos (RUVs) to investigate whether reef fishes consistently forage on specific habitats across 5 different oceanic islands in the Atlantic Ocean, especially focusing on the importance of the role of hyperdominant species. We analysed 295 RUVs, within 2 m2 areas (3-15 m deep), totalling 49 h of video. Photoquadrats were utilised to gauge benthic group coverage in the same habitats. Our results revealed 5 prevalent habitats and 6 fish trophic groups interacting with reef benthos. The intensity of feeding pressure varied across islands, depending on the diversity of habitats. Herbivores and omnivores exhibited the highest feeding pressure, with omnivores foraging on crustose coralline algae and macroalgae habitats, while herbivores primarily fed on habitats dominated by the epilithic algal matrix. Hyperdominant species forage in multiple habitats, indicating a comparatively high degree of dietary plasticity. Our findings also demonstrated that fish feeding pressure is influenced by both habitat features and fish biomass. Therefore, our study can provide valuable insights for prioritising the management of key species in isolated oceanic reefs.

Widespread occupancy of the Endangered northern myotis on northeastern Atlantic Coastal Plain islands

Widespread occupancy of the Endangered northern myotis on northeastern Atlantic Coastal Plain islands

Sea turtle stranding records and fishing interactions on an Oceanic Atlantic Island (Tenerife, Canary Islands)

Sea turtle stranding records and fishing interactions on an Oceanic Atlantic Island (Tenerife, Canary Islands)