Canary Islands Research Articles

Tiltmeter Data Revealing Transient Magma Viscosity Changes During Eruptions

Volcanic processes related to episodes of inflation, dike propagation, effusive activity, etc., can be detected by continuous surface tilt measurements. The interpretation of these measurements helps comprehend medium-to-short-term precursors of volcanic eruptions or establishes early warning alerts. Additionally, studying the transport and evolution of magmas from the Moho to the crust is key to understanding the eruptive process, but to date, they have not been traced from surface tilts. In this work, we witnessed two relevant and unique dynamic eruptive processes, as revealed by tilt signals, both in the 2021 La Palma eruption and in the 2011–2012 El Hierro eruption (Canary Islands). On the one hand, magma injection from the reservoir at depth is controlled by a pressure gradient. On the other hand, changes in magma viscosity, resulting from pressure variations, have been revealed from cyclic tilt signals. In the case of these signals, matching with a physical model helped us decipher them and establish the duration of this magmatic process, which varied depending on the size and rheological properties of the respective magma plumbing systems.

Corrigendum: Distribution of cetaceans in the Canary Islands (Northeast Atlantic Ocean): implications for the Natura 2000 Network and future conservation measures

Corrigendum: Distribution of cetaceans in the Canary Islands (Northeast Atlantic Ocean): implications for the Natura 2000 Network and future conservation measures

A New Pyrrole Alkaloid from Capsicum annuum L. var. palmera Grown in La Palma (Canary Islands, Spain)

Capsicum annuum, commonly known as pepper, is a widely cultivated crop valued for its nutritional and economic significance. Among its varieties, the small red bell pepper, locally known as “pimienta palmera”, is a unique cultivar from La Palma in the Canary Islands, renowned for its distinctive flavor and use in traditional dishes. Despite its cultural importance, limited research exists on the chemical composition of this pepper variety. This study investigates the chemical constituents of dichloromethane and n-butanol fractions extracted from the pericarp of Capsicum annuum var. palmera. Isolation and structural elucidation of compounds were achieved using high-resolution mass spectrometry (HREIMS), nuclear magnetic resonance spectroscopy (NMR), and chromatographic techniques. A previously unreported pyrrolo-lactone compound, 2-(6-formyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazin-4-yl)acetic acid, was identified alongside other metabolites, including α-tocopherol, β-sitosterol, and oleic acid. This alkaloid adds to the chemical diversity of Capsicum species and highlights the unique bioactive potential of this regional pepper. These findings enhance the understanding of pimienta palmera’s composition and suggest potential applications in nutraceuticals and pharmacology due to the biological activity associated with pyrrole alkaloids. The characterization of this compound underscores the need to further explore the phytochemical richness of traditional crops with limited prior research.

Whistle Characteristics of the Rough-Toothed Dolphin (Steno bredanensis) in the Canary Islands

Whistle Characteristics of the Rough-Toothed Dolphin (Steno bredanensis) in the Canary Islands

Gendered dynamics in Moroccan transnational migrant networks in Tenerife: environmental concerns, engagement, and remittances

The concept of transnational knowledge networks has entered the field of study of environmental mobility. Yet, how these networks play a role in adaptation to environmental change remains understudied. Power dynamics and familial ties impact the functioning of transnational networks and intricately shape responses to environmental challenges, with gender serving as a salient factor. This research aims to theorize and empirically study how gender matters for how men and women engage with environmental concerns within transnational spaces of Moroccan migrants living in Tenerife, the largest of the Canary Islands. This study employs visual mapping techniques to uncover gendered patterns and modalities of communication within transnational networks. Findings reveal significant gender disparities in how environmental challenges are discussed and addressed within Moroccan transnational networks. While women prioritize family welfare and employ cultural practices to tackle environmental issues, men focus more on economic implications. Women’s perspectives and voices are marginalized, reflecting societal gender norms and biases that prioritize men’s voices and expertise in economic matters. This ignorance hinders their participation and access to support within transnational networks, perpetuating gender disparities in engagement and decision-making.

Evolution of warm nights in the Canary Islands (1950–2023): evidence for climate change in the Southeastern North Atlantic

Nighttime temperatures have a direct impact on the health and well-being of the population, and are closely linked to the aggravation of certain pathologies and mortality. As global warming acquires extraordinary magnitudes, concepts such as warm night, tropical night or equatorial night, used as indicators to evaluate the evolution of temperatures during the night, are becoming popular. This paper analyses the evolution of nighttime temperatures in the Canary Islands since 1950, identifying a very notable increase in the daily minimum temperature, particularly at the summits, where the rate of increase exceeds 0.2 °C per decade. Overall, the daily minimum temperature easily reaches 20 °C in many parts of the islands, with a statistically significant upward trend in the frequency of tropical nights. In addition, they tend to occur over an increasingly longer season, more consecutively and with greater thermal intensity. Equatorial nights — ≥ 25 °C— are still an eminently summer phenomenon of growing importance in certain areas of the inland of some islands. Torrid nights — ≥ 30 °C—, on the other hand, are associated with extremely warm episodes that affect specific sectors conditioned by local factors.

Isolation of a Novel Caprine Eimeria christenseni Strain (GC) in Canary Islands and Analysis of Parasitological, Clinical, and Pathological Findings on Experimentally Infected Goat Kids

Eimeria christenseni is considered among the most pathogenic Eimeria species in goats. The aim of this study was to isolate an E. christenseni strain and to assess its infectivity, pathogenicity, and ability to develop a protective immune response. After previous collection of E. christenseni-positive faeces, purification of oocysts, and amplification in donor animals, an experimental infection was carried out. A total of 19 kids were divided into three groups: primary-infected and challenged, challenge control, and uninfected control. Infections were performed orally with 2 × 105 sporulated oocysts per animal. Oocyst shedding, clinical signs, and production parameters, in addition to haematological and histopathological features, were monitored. The results showed that the Gran Canaria (GC) E. christenseni strain had similar morphological and biological characteristics to those previously described, but no significant clinical signs were observed despite the high oocyst counts here recorded. The novel strain isolated would therefore be of low pathogenicity but still able to develop significant immunoprotective responses upon challenge infections. Its biological similarities to highly pathogenic species such as Eimeria ninakohlyakimovae and Eimeria arloingi might enable comparative studies aimed at developing alternative strategies for drug treatments, including Eimeria species (strain)-specific vaccination strategies for the efficient control of goat coccidiosis.

Emergence and Development of a News Hate Cycle About Immigrants: The Case of Immigrants Transferred from the Canary Islands to the Spanish Mainland

In this article, we present the findings of research focused on the emergence and development of an immigration-related news hate cycle in Spain. During the period from 24 to 29 October 2023, there was an unusual increase in social media posts about the Spanish government’s transfer of immigrants from the Canary Islands to the Spanish mainland. Based on the monitoring of 918 posts collected through AI media-monitoring software (Determ d.o.o), our study identify how hate speech against immigrants was generated and spread. In particular, we aim to identify the main actors and influencers involved in its creation, dissemination, and transformation, and how these actors manipulate interpretative frameworks by introducing arguments about a supposed comparative grievance between the Spanish people and immigrants in order to foment hatred and strengthen attitudes of rejection towards immigrants, presenting them as invaders, criminals, and terrorists. In this news cycle, hate speech reaches its peak when the press of trustworthy information echoes the disinformation. The analysis of the actors involved and the temporal sequence on social media and websites reveals how they achieve this. It also allows us to develop tools to counter the spread of hate speech.

Tracing metals in Mediterranean and Atlantic Sardina pilchardus: Unveiling impacts on food safety.

This study evaluates the concentration of metals and trace elements (Al, Cd, Cu, Fe, Li, Pb, Zn) in the muscle tissue of Sardina pilchardus from three northeast Atlantic localities (Lisbon, Canary Islands, Rabat) and two western Mediterranean sites (Málaga, Cartagena) to assess food safety and environmental impact. A total of 100 sardines were sampled between January and June 2019, with specimens collected, homogenized by size and weight, and analyzed for metal content using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). Results show significant geographical variation in metal concentrations, with Cartagena exhibiting the highest levels due to industrial and urban activities, while the Canary Islands had the lowest, likely influenced by geographical isolation and stringent environmental regulations. Intermediate levels were observed in Lisbon, Rabat, and Málaga, with Rabat ranking second highest. Importantly, none of the samples exceeded EU safety limits for lead (0.3mg/kg) or cadmium (0.25mg/kg), confirming their suitability for human consumption regarding metal content. These findings emphasize the role of local environmental and industrial factors in influencing metal bioaccumulation in marine ecosystems. Genetic and ecological dynamics, such as the Almería-Oran Front and the Canary Islands' isolation, likely contribute to these patterns. The study underscores the importance of continuous monitoring to safeguard food safety and marine ecosystem health. Despite Cartagena's elevated contamination levels, which pose a higher potential risk if sardine consumption is frequent, sardines from all locations remain within safety limits. Moving forward, research should prioritize long-term monitoring and explore genetic and ecological factors influencing bioaccumulation trends, contributing to sustainable management and effective pollution control measures. This highlights the interconnectedness of environmental health and human dietary safety, emphasizing the need for a proactive approach to monitoring marine contamination.

Km-scale climate simulations over Madeira and Canary Islands under present and future conditions: a model intercomparison study

This study seeks to explore two new km-scale regional climate simulations prepared through the European Climate Prediction project over the Madeira and Canary islands, which are Portuguese and Spanish archipelagos located in the North Atlantic, off the African coast. The simulations are based on two models using different modelling approaches: COSMO-CLM with a three-step nesting at 50, 25 and 3 km grid spacing using a time-slice approach driven by a global climate model, and COSMO-crCLIM with a two-step nesting at 12 and 1 km grid spacing using the pseudo-global warming approach, where the current-day simulations are driven by ERA-Interim reanalysis. Although the modelling approaches are different, several findings are highlighted: (1) the use of km-scale simulation is essential to properly represent temperature and precipitation mean and extremes over small islands that are characterized by complex topography; (2) the projected changes in temperature and precipitation mean and extremes are qualitatively similar in all seasons except autumn; (3) the differences in the autumn projections are shown to be due to the large-scale driving conditions. Small islands, such as the Canary and Madeira ones, are often neglected by large modelling initiatives, so the presented simulations contribute to filling this gap for local policy makers, stakeholders and climate services. The encouraging results highlight the need for further coordinated km-scale projections.

Hotel profitability in Spain: Impact of the location of tourist destinations

Purpose - This paper evaluates the impact of the location of tourist destinations on Spanish hotel profitability. For this purpose, the factors that describe tourism profitability are identified and clusters of tourist destinations are developed. The model also analyses the determinants of profitability based on location models developed in the hotel sector, such as accessibility, agglomeration, and seasonality of the tourist destination. Methodology - Multivariate analysis techniques and non-parametric contrasts are applied. Findings - The results highlight the importance of the location of tourist destinations, the preferred tourist mode, and the level of seasonality on tourist profitability. There is an economic, labour and efficiency imbalance that benefits coastal vacation destinations with lower levels of seasonality, located in the Mediterranean strip, the Balearic Islands, and the Canary Islands. Originality - Special attention is paid to factors related to the location of tourist destinations from the perspective of both supply and demand, which makes it possible to isolate and quantify the effect of the tourist destination on profitability, which is essential for good planning and management.

Improvements in the design of brine diffusers in shallow waters: A numerical study applied to the Canary Islands

Improvements in the design of brine diffusers in shallow waters: A numerical study applied to the Canary Islands

Genetic diversity and population structure of Canarian chicken using microsatellite DNA markers

The Canary Islands have historically been a crossway among at least three continents; therefore, the genetic influences on their local animal breeds have been extremely diverse. In the Canarian chicken population, genetic diversity is evident but it has never been studied. The aim of this study was to assess the population structure and genetic diversity within the Canarian chicken population, as well as between the Canarian chicken population, the Spanish local populations, and the commercial chicken populations with microsatellites, with a view to reinforce the official recognition of the breed, for the design and development of a conservation program. Blood samples were collected at random from 198 animals of the Canarian and compared with Spanish local and commercial strains, in order to determine differentiation and genetic relatedness. The five phenotypic varieties of Canarian chicken, the population structure and genetic diversity within the Canarian chicken population had a higher unbiased expected heterozygosity than the observed heterozygosity. Comparing the Canarian vs other local Spanish breeds and commercial strains, FST was relatively high (0.179) (0.164 – 0.195), the neighborhood network showed that the Canarian varieties did not cluster with the other Spanish breeds. The STRUCTURE, confirmed that the Rubilana variety differed from the other four Canary Islands. We conclude that the Canary Islands chicken population shows a differentiated genetic profile, versus other Spanish and cosmopolitan breeds. The theory that the existence of genetic varieties is based on the color of feathers was definitively discarded, except in the Rubilana population, which could be admitted as a genetically different variety.

Molecular identification of newly recorded Lepidoptera for Cyprus and Europe (Insecta: Lepidoptera)

As part of a comprehensive molecular inventory of Lepidoptera in Northern Cyprus, 8 species have been identified as new records for the island of Cyprus through genetic comparisons of DNA barcodes with reference sequences. The following species are formally reported for the first time in Europe: Coleophora bivittella Staudinger, 1879 (Coleophoridae) and Teliphasa lophotalis (Hampson, 1900) (Pyralidae), whereas the agriculturally significant species Spodoptera frugiperda (Smith, 1797) (Noctuidae) was only published from the Canary Islands (Spain) and from Malta so far. The possibilities and limitations of molecular-based determinations are briefly discussed using the example of the fauna of north Cyprus.

A new species of Mysidopsis (Crustacea, Mysida) from the Canary and Cape Verde archipelagos.

Within the subfamily Leptomysinae (fam. Mysidae), the tribe Mysidopsini has five here acknowledged genera and 74 extant species. It embraces the genera Americamysis with six species from the coasts of the NW-Atlantic (Narragansett Bay to Florida), the Caribbean and Gulf of Mexico; Brasilomysis with two species from the SW-Atlantic off Brazilian shores and from the Pacific coast of Ecuador; Cubanomysis with three species from the Caribbean, Gulf of California and southern California; Metamysidopsis with ten species from the Atlantic coasts of the USA to Brazil, Caribbean, Gulf of Mexico and E-Pacific from California to Panama; and, finally, the globally occurring Mysidopsis. Not counting the below-described new species and one fossil species, the latter genus comprises 53 extant species and one non-nominotypical subspecies. With regard to the great number of species, this genus is comparatively homogeneous, not considering the monotypic subgenera Pseudomysidopsis and Mysidopsoides. Mysidopsiscanariensis sp. nov. is described from five islands of the Canaries and two islands of the Cape Verdes (NE-Atlantic). Records are from depths of 5 to 30 m, mainly over sand, also on stones and rock. It differs from the remaining NE-Atlantic and Mediterranean congeners amongst other features by the lateral margins of the telson distally having a longer bare portion. Amongst these species, it differs from its northern vicariants M.iluroensis and M.gibbosa in addition by fewer spines on the endopod of uropods. In-situ-photos of M.canariensis sp. nov. document at least six strongly different colour variants, four of which are strikingly similar to corresponding variants of M.jenseni from the NE-Pacific coast. The latter differs from all species of the E-Atlantic, including the new one, by a mid-dorsal lappet near the caudal margin of the female carapace. A key to the species of Mysidopsis from the E-Atlantic and Mediterranean is given.

Extending beyond traditional forage: potential nutritional benefits of native plants in extreme arid insular regions.

The scarcity, unstable nutritional quality and environmental cost of imported forages in arid insular regions like Fuerteventura in the Canary Islands (Spain) need exploring sustainable local alternatives. This study evaluated the nutritional quality of twelve native and endemic plant species categorized into legumes, grasses, and a mixed group, cultivated under controlled conditions. The bromatological profiles, focusing on fiber, protein, lipids, and minerals, showed significant differences among plants in key parameters of forage quality: neutral detergent fiber (NDF; 24.2-71.3%), acid detergent fiber (ADF; 9.0-40.5%), acid detergent lignin (ADL; 2.0-15.8%), crude protein (CP; 6.1-20.9%), total lipids (TL; 1.5-6.3%), ash content (25.4-88.6%), enzymatic organic matter digestibility (EOMD; 5.9-10.9 MJ/kg), metabolizable energy (ME; 5.9-10.9 MJ/kg), and relative feed value (RFV; 74.8-317.9). Among lipids, all species had a high proportion of polyunsaturated fatty acids (PUFA; 34.7-63.1% of total fatty acids), mainly α-linolenic acid (ALA; 18:3 n-3; 24.8-54.4%) and linoleic acid (LA; 18:2 n-6; 6.4-25.0%). Other beneficial lipid molecules for animal health such as γ-linolenic acid (GLA; 18:3 n-6), stearidonic acid (SDA; 18:4n-3) and phytosterols (PTS) were detected in specific species. Mineral composition analysis revealed that only Ca, Na, Fe and Cu levels were near or above the established maximum tolerable levels (MTLs) in some species. According to literature, most of the species had a similar or slightly lower nutritional value compared to conventional forages such as alfalfa. Thus, the evaluated native species pool could serve as alternative feed for ruminants during forage shortages, suggesting their combined use to improve livestock health and product quality. This research emphasizes the untapped potential of native plant biodiversity to enhance sustainable agro-livestock practices in arid regions, supporting livestock nutrition and conserving unique botanical heritage.

A Fuzzy Decision Support System for Real Estate Valuations

The field of real estate valuations is multivariate in nature. Each property has different intrinsic attributes that have a bearing on its final value: location, use, purpose, access, the services available to it, etc. The appraiser analyzes all these factors and the current status of other similar properties on the market (comparable assets or units of comparison) subjectively, with no applicable rules or metrics, to obtain the value of the property in question. To model this context of subjectivity, this paper proposes the use of a fuzzy system. The inputs to the fuzzy system designed are the variables considered by the appraiser, and the output is the adjustment coefficient to be applied to the price of each comparable asset to obtain the price of the property to be appraised. To design this model, data have been extracted from actual appraisals conducted by three professional appraisers in the urban center of Santa Cruz de Tenerife (Canary Islands, Spain). The fuzzy system is a decision-helping tool in the real estate sector: appraisers can use it to select the most suitable comparables and to automatically obtain the adjustment coefficients, freeing them from the arduous task of calculating them manually based on the multiple parameters to consider. Finally, an evaluation is presented that demonstrates its applicability.

Unexpected Genetic Diversity of Nostocales (Cyanobacteria) Isolated from the Phyllosphere of the Laurel Forests in the Canary Islands (Spain).

A total of 96 strains of Nostocales (Cyanobacteria) were established from the phyllosphere of the laurel forests in the Canary Islands (Spain) and the Azores (Portugal) using enrichment media lacking combined nitrogen. The strains were characterized by light microscopy and SSU rRNA gene comparisons. Morphologically, most strains belonged to two different morphotypes, termed "Nostoc-type" and "Tolypothrix-type". Molecular phylogenetic analysis of 527 SSU rRNA gene sequences of cyanobacteria (95 sequences established during this study plus 392 sequences from Nostocales and 40 sequences from non-heterocyte-forming cyanobacteria retrieved from the databases) revealed that none of the SSU rRNA gene sequences from the phyllosphere of the laurel forests was identical to a database sequence. In addition, the genetic diversity of the isolated strains was high, with 42 different genotypes (44% of the sequences) recognized. Among the new genotypes were also terrestrial members of the genus Nodularia as well as members of the genus Brasilonema. It is concluded that heterocyte-forming cyanobacteria represent a component of the phyllosphere that is still largely undersampled in subtropical/tropical forests.

Patterns of intraspecific genetic variation of Andoa berthelotiana (Myuriaceae, Bryophyta) in the Azores (Macaronesia)

Macaronesia is home to several endemic bryophytes, such as Andoa berthelotiana. Recent genetic studies revealed the existence of two intraspecific lineages within this species, one in Madeira and the Canary Islands and another in the Azores. However, patterns of intraspecific variation within archipelagos, remain a relatively unexplored area of research. In this study we investigate patterns of intraspecific variation of Andoa berthelotiana within the Azorean archipelago and potential associations with elevation. Our investigation is based on the analysis of chloroplast DNA sequences and AFLP data. The dataset includes trnL-trnF sequences from 23 samples and AFLP data from 34 samples collected in seven of the nine Azorean islands, encompassing elevations of up to 1200 m. For the DNA sequence data haplotype diversity, nucleotide diversity and a statistical parsimony haplotype network were calculated. The AFLP data were analyzed by AMOVA (Analysis of Molecular Variance) and PCoA (Principal Coordinates Analysis). A Chi-Square test was carried out to assess the significance of the relationship between elevation and AFLP groups or trnL-trnF haplotypes, respectively. The observed intraspecific genetic variation clustered into three trnL-trnF haplotypes and two AFLP groups, without a clear geographical structure across the Azorean archipelago. Group AFLP1 and haplotypes trnL_F1 and trnL_F3 only appeared below 600 m elevation, where low-elevation vegetation (coastal woodlands, lowland forests and montane Laurus azorica forests) prevails, while group AFLP2 and haplotype trnL_F2 occurring along the whole elevational range, but with most samples above 600 m. Associations between elevation and molecular groups were significant according to the Chi-Square test. Our study reveals the presence of genetic variation within Andoa berthelotiana in the Azorean archipelago. The two main genetic groups do not seem to be related to geographical location of islands nor groups of islands, but rather to elevation. One group exhibits a broader ecological amplitude, whereas the other may be genetically adapted to environmental conditions at lower elevations (below 600 m), which includes the area where the native laurel forests dominate and where anthropogenic activities have altered the majority of natural vegetation. Conservation efforts should therefore not only consider the species Andoa berthelotiana itself, which is associated with natural forest, but also intraspecific genetic diversity of Andoa populations, in particular genotypes restricted to lower elevations.

Validation of the PECUNIA reference unit costs templates in Spain: a useful tool for multi-national economic evaluations of health technologies

BackgroundThe PECUNIA Project was funded by the H2020 programme in which 10 partners from six countries participated. The aim was to develop standardized, harmonized and validated methods and tools to calculate costs in different sectors (such as health and social care, education among others), with the purpose of facilitating comparability of economic evaluations of health technologies across European countries. In this paper we report the first validation of the developed reference unit cost templates in Spain.MethodsThe evaluation of the PECUNIA Reference Unit Cost (RUC) Templates involved usability, transferability and feasibility assessment. Applicability tests were performed to estimate the cost of a selection of 15 resource items by means of the RUC templates in Spain and in four Spanish regions. External validation involved comparison with existing unit costs.ResultsIt was possible to estimate the cost of five services (dental care and general practitioner in the Canary Islands, general practitioner in Spain [tariffs], health-related day care centre and education services provided in a special education school in the Basque Country), car vandalism as an example of potential health-related consequences, and informal care in Spain. The templates were feasible although data completeness depended on the type of data needed to estimate the costs. The templates are transferable across countries although comparability depends on the services available in each jurisdiction.ConclusionsThe PECUNIA RUC Templates are free and feasible tools to estimate comparable reference unit costs across countries. Although more validation exercises are needed, they seem useful tools to perform robust multi-national economic evaluations and increase the transferability of cost-effectiveness studies of health technologies in Europe. However, they cannot compensate for the lack of data across jurisdictions.