Canary Islands Research Articles

Diversity of Ladybird Beetles (Coleoptera: Coccinellidae) in Tenerife and La Gomera (Canary Islands): The Role of Size and Other Island Characteristics.

This paper provides new data on the ladybird beetles (Coccinellidae) from two islands in the Canary archipelago: Tenerife, the largest island, and La Gomera, the second smallest. As they clearly differ in size but are similar in location and geological age, they are a suitable model for testing the species-area relationship. Our study shows that, in line with this main assumption of the theory of island biogeography, clearly more species occur on a large island (Tenerife) than on a small one (La Gomera). The field surveys documented the occurrence of 35 ladybird species on Tenerife (including 5 not previously reported from this island) and of 20 species on La Gomera (2 species new to the island). Coelopterus sp. collected on Tenerife (a single female that could not be identified to species) is the first record of this genus for the whole Canary Islands. Taking our data and previously published records into account, 47 species of Coccinellidae are known to occur on Tenerife and 26 species on La Gomera. Tenerife has by far the richest ladybird fauna of all the Canary Islands (the next in line, Gran Canaria, has 41 recorded species), but it also has the highest number of non-native ladybird species. All of the ten non-native species recorded in the Canary Islands are found on Tenerife, and for most of them, Tenerife was the island of their first appearance in the archipelago. This island, much more distant from the mainland than the other relatively large islands (Fuerteventura, Lanzarote), appears to be the main recipient of ladybirds immigrating to the Canary Islands. Tenerife can play this role probably because of its great habitat diversity and altitude variation, as well as intensive tourism and trade-related transport.

Understanding Balanophyllia regia Distribution in the Canary Islands: Effects of Environmental Factors and Methodologies for Future Monitoring

The future of marine ecosystems is at risk due to climate change and other human impacts. Specifically, due to ocean warming, some tropical species are expanding their populations while populations of temperate species are in regression, making the establishment of conservation measures imperative to maintain local biodiversity. In this study we establish a baseline on the distribution and abundance of the temperate coral Balanophyllia regia from the Canary Islands. We found that the main environmental factors determining B. regia’s distribution and abundance were sea surface temperature and hydrodynamic conditions. Areas under large wave action and colder environments enhanced this warm-temperate species’ development. Since its metabolic performance depends exclusively on the surrounding environment, we also propose a methodology to potentially monitor climate change on coastal habitats through this azooxanthellate calcified coral. Results of a tagging experiment showed that a concentration of 20 mg/mL of calcein during 6 h might be enough to in situ label polyps of B. regia without compromising corallite survival. Long-term monitoring of population abundances and growth rates of B. regia through calcein tagging will allow us to identify alterations in local ecosystems early and focus future conservation investments on the most vulnerable areas with higher ecological and economic value.

Clinicopathologic findings and causes of mortality in 100 pet rabbits from the Canary Islands, Spain, 2011-2022.

The European domestic rabbit (Oryctolagus cuniculus domesticus) is commonly kept as a pet, with increasing popularity among pet owners. Despite the increasing body of information on lagomorph medicine and pathology, comprehensive published compilations of causes of mortality in pet rabbits are limited. We analyzed health disorders, pathology findings, and most probable causes of death in 100 pet rabbits submitted to the Anatomopathological Diagnostic Service of the Veterinary School of the University of Las Palmas de Gran Canaria, Canary Islands, Spain, from 2011 to 2022. We reviewed clinical data and gross and histopathologic findings to classify the various disorders into infectious (n = 39), noninfectious (n = 45), and idiopathic conditions (n = 16). Within infectious disease processes, Encephalitozoon cuniculi infection (n = 14) and rabbit hemorrhagic viral disease (n = 14) had the highest prevalence. Regarding the noninfectious conditions, perioperative mortality (n = 10), gastrointestinal syndrome (n = 7), and trauma (n = 6) were the most common clinicopathologic entities observed.

Analysis of development of floating offshore wind energy in Spain

Offshore wind energy generation has developed rapidly especially in the last decade. In some countries, despite having good wind conditions for its development, it has not been possible to implement it. This is because its continental shelf is very short, that is, the land under water in shallow seas is not wide enough to install fixed foundations. Consequently, the development of floating platforms is awakening interest in this type of generation, as is the case in Spain. In this article, a methodology for calculation the generated electrical energy in floating offshore wind farms and the corresponding losses is developed. In this way, all necessary data involved in the methodology have been obtained from the sites destined for offshore wind development. These emplacements have been released by Spanish Government in recently approved Maritime Spatial Plan. The generation potentials in Spanish waters have been evaluated according to most interesting ratios as levelized cost of energy, capacity factor and cost of installed megawatt. Results show that most of emplacements are interesting enough for the development of OWFs. Deserve to be mentioned three main areas, such as, northwest waters, Canary Island zones and north part of Catalonia.

Physicochemical and Nutritional Characterization of Green Banana Flour from Discarded Cavendish Bananas

Fifteen percent of harvested bananas are discarded daily in the Canary Islands at packing houses because of marketing standards, mainly based on their appearance, or are retired to avoid falls in the market price of bananas. This discarded fruit is an environmental issue, and green banana flour (GBF) is an interesting management alternative for it. In this paper, the artisanal process for obtaining GBF was optimized. The study of physicochemical and nutritional characteristics of this gluten-free flour indicated a high contribution of starch, fiber, phenolics, K, and Mg to dietary intake. Storage of GBF at room temperature (20 ± 5 °C) for ten months slightly increased its moisture and acidity and decreased its starch content, phenolic content, and pH. Some color changes were observed after 5 months, but sensory characteristics were still acceptable after ten months. Green bananas storage prior to GBF elaboration showed they were suitable for obtaining good quality GBF even after 7 weeks at 6 °C, but only 4 weeks at 12 °C. Discriminant analysis classified the GBF correctly according to the cooperative origin, time, and storage temperature of the bananas used in its preparation. These results provide information that could be used in other banana-producing regions for reducing the environmental impact of fruit waste and obtaining GBF using a simple and inexpensive technological process.

Diversity of ecotypes of five species of ryegrass from Northwestern Spain by phenotypic traits and microsatellites

BackgroundThe Agricultural Research Centre of Mabegondo (Xunta de Galicia, A Coruña, Spain) conserves one of the most important collections of phytogenetic resources of ecotypes and natural populations of grassland species from northwestern Spain, among them populations of ryegrass (Lolium spp.), one of the most cultivated forage grasses in the world. The objective of the present study was to evaluate the diversity among commercial cultivars and natural ryegrass populations with phenotypic traits and molecular markers.ResultsEleven polymorphic microsatellites loci were used to analyze 58 ecotypes and 10 cultivars (680 DNA samples in total) differentiating 673 genotypes. Two main groups were detected by the Structure analysis, one related to Lolium perenne and a second to Lolium multiflorum. The first group showed two subgroups and the second three. The cluster of L. multiflorum showed two subgroups not related with the third cluster including commercial varieties, one from the Canary Islands (with Lolium rigidum included) and a second one from northwestern Spain, which presented specific agromorphological characteristics, such as lower FES (number of days from 1 January, when three heads per plant were flowering per plot), CRE (growth in flowering, in g of dry matter), and AIN (number of inflorescences per plant).ConclusionsThis is the first time that a large amount of data on ryegrass from the Iberian Peninsula has been analyzed, obtaining a clear genetic differentiation of the autochthonous varieties from the commercial varieties analyzed. In addition, the genetic structure found in the ecotypes was related to the phenotypic variation analyzed. Being of interest in the conservation of biodiversity and in obtaining better adapted varieties of ryegrasses, due to their specific phenotypic traits, such as a lower FES, CRE and AIN.

Anthropogenic debris pollution in yellow-legged gull (Larus michahellis atlantis) nests in biosphere reserves of the Canary Islands

Anthropogenic debris, particularly plastic pollution, has emerged as a significant environmental threat to biodiversity. Given that seabirds interact with artificial debris through ingestion, entanglement, and nest incorporation, it is particularly important to quantify the quantity, origins, and chemical composition of these debris items. In this work, it was evaluated for the first time the occurrence of anthropogenic debris in nests of yellow-legged gull (Larus michahellis atlantis) in biosphere reserves of the Canary Islands (Spain). A total of 48 abandoned nests were collected from five remote and hardly accessible sampling areas, revealing that 81.3 % contained anthropogenic waste, with plastic accounting for 34.7 % of the debris, followed by metal (33.6 %) and paper (19.6 %). On average, 32.8 ± 40.9 items were found per nest. Regarding the origin, food packagings (47.8 %), personal hygiene products (21.7 %), and textiles (15.8 %) were identified as the predominant sources. Furthermore, the polymer composition of the plastics was characterised by means of Fourier-transform infrared spectroscopy analysis, being polyester the most abundant (38.2 %), followed by polyethylene (25.6 %) and rayon (10.3 %). The incorporation of anthropogenic debris into nest construction may result from outdoor human activities carried out far from nesting areas.

Genomics of ecological adaptation in Canary Island Descurainia (Brassicaceae) and comparisons with other Brassicaceae.

Oceanic archipelagos provide striking examples of lineages that have radiated over pronounced ecological gradients. Accompanying this diversification, lineages have evolved adaptations allowing survival in extreme environments. Here, we investigate the genomic basis of ecological adaptation in Canary Island Descurainia (Brassicaceae), an island relative of Arabidopsis. The seven endemic species have diversified insitu along an elevational and ecological gradient, from low-elevation scrub to high-elevation sub-alpine desert. We first generated a reference genome for Descurainia millefolia, phylogenetic analysis of which placed it as sister to D. sophioides. Ninety-six gene families were found to be specific to D. millefolia and a further 1087 and 1469 gene families have expanded or contracted in size, respectively, along the D. millefolia branch. We then employed genome re-sequencing to sample 14 genomes across the seven species of Canary Island Descurainia and an outgroup. Phylogenomic analyses were consistent with previous reconstructions of Canary Island Descurainia in resolving low- and high-elevation clades. Using the branch-site dN/dS method, we detected positive selection for 275 genes on the branch separating the low- and high-elevation species and these positively selected genes (PSGs) were significantly enriched for functions related to reproduction and stress tolerance. Comparing PSGs to those in analyses of adaptation to elevation and/or latitude in other Brassicaceae, we found little evidence of widespread convergence and gene reuse, except for two examples, one of which was a significant overlap between Descurainia and Draba nivalis, a species restricted to high latitudes. The study of Canary Island Descurainia suggests that the transition to high-elevation environments such as that found in the high mountains of the Canary Islands involves selection on genes related to reproduction and stress tolerance but that repeated evolution across different lineages that have evolved into similar habitats is limited, indicating substantially different molecular trajectories to adaptation.

An ant-mimicking ant on an oceanic archipelago: Camponotus guanchus mimics Crematogaster alluaudi-An analogy with the situation of Camponotus lateralis (Hymenoptera: Formicidae).

Mimicry, that is, the imitation of any unpalatable or defensive species by another, has been of central interest to evolutionary research since Darwin's lifetime. Two ant species, Camponotus guanchus Santschi, 1908 and Crematogaster alluaudi Emery, 1893, endemic to the Canary Islands, occur in two color-morphs: While the head of workers is always reddish and the gaster blackish, the mesosoma (inclusive waist) is either fully reddish or fully blackish. In addition to the obvious morphological and coloration similarities, we provide evidence of mimicry: (i) Ca. guanchus was found only within the area of Cr. alluaudi. (ii) Color morphs are geographically non-randomly distributed: Workers of both species from 16 localities of syntopic occurrences shared in eight cases a blackish and in eight cases a reddish mesosoma. Hence, Ca. guanchus mimics both local color-morphs of Cr. alluaudi. We consider a fascinating analogy with the Mediterranean mimicry system in Camponotus lateralis (Olivier, 1792) and its model species of the Crematogaster scutellaris (Olivier, 1792) group on an island scale. Additionally, we present two endemic bug species, Perenotus stysi (Ribes etal., 2008) and P. malobae Roca-Cusachs & Goula, 2016, as mimics of those Cr. alluaudi workers having a reddish mesosoma. Our distribution, coloration, frequency, and behavioral data as well as the analogy with Ca. lateralis and the Cr. scutellaris group suggest a Batesian-mimicry system in which Ca. guanchus, Perenotus stysi, and P. malobae mimic the unpalatable and aggressive Cr. alluaudi as an antipredator adaptation.

Metal variability in small pelagic fish Scomber colias as influenced by volcanic events in the Canary Islands.

Offshore volcanic activity occurs when an underwater volcano erupts. These volcanoes can be located underwater or on land and can be very dangerous to marine life. The aim of this study is to examine whether the influence of two volcanoes has an effect on the concentrations of metals and trace elements in the Atlantic mackerel Scomber colias in the Canary Islands. For the study, ten specimens of S. colias were obtained from each sampling area in March 2022. Metal concentrations were determined by inductively coupled plasma optical emission spectrophotometry (ICP-OES). The specimens of Scomber colias from the area affected by the Tajogaite volcano (La Palma) showed higher concentrations of all metals and trace elements analyzed than those from the other study areas. The specimens from the area of influence of the Tagoro Volcano (El Hierro) showed the second highest concentration of the elements studied, although this volcanic process is in a state of degassing.

Assessment of the water quality of spring “La Mina”. Groundwater of Parque Rural del Nublo. Biosphere Reserve by UNESCO. Gran Canaria. Canary Islands

Assessment of the water quality of spring “La Mina”. Groundwater of Parque Rural del Nublo. Biosphere Reserve by UNESCO. Gran Canaria. Canary Islands

Chemical, mineralogical and geotechnical properties of volcanic ash of Tajogaite (La Palma, Canary Islands, Spain)

Volcanic eruption at La Palma island (Tajogaite, 2021) has produced tons of volcanic ash as natural sediments spread all around the island covering existing crops, roads, embankments, buildings, etc., by that way producing damage to environment. For the rehabilitation and reconstruction of island, and its application to adjacent areas, it is practical and economical to employ these volcanic ashes as construction material being encountered in abundant volume, and by that way could be considered as a resource material instead as a waste material, reducing necessary volume of landfills for its deposition. This paper defines the investigation of chemical, mineralogical and geotechnical properties of these deposited materials for its possible reuse by that way providing solution for its recovery. These young volcanic ashes are studied in its fresh natural state, prior to consolidation and cementation has taken place for its chemical, mineralogical and geotechnical characterization. Volcanic ash of Tajogaite is of a poorly graded sandy nature having difficulties for its compaction, having low improvement of relative density by the application of standard compaction methods. Mineralogy analysis indicates it is rich in silica, iron, calcium and alumina oxide, although being necessary the addition of mineral additives for its alkali-activation. Geotechnical characteristics of different samples vary depending on the sampling site, being resistance parameters determined by direct shear test (friction angle 30° to 34°) and deformational properties defined by one-dimensional consolidation test considered low values as of loose sand materials (deformation modulus range from 20 to 40 MPa).

First Report of Acanthamoeba Genotype T4 from the Newly Formed Tajogaite Volcano Tephra (La Palma, Canary Islands).

The Tajogaite Volcano erupted on the western slope of the Cumbre Vieja mountain range on La Palma Island in the Canary Islands, Spain, in 2021. As one of the multiple consequences of this eruption, a layer of tephra was deposited, to a variable extent, over a large part of the island. Tephra deposits affect all aspects of vegetation recovery, the water cycle, and the long-term availability of volcanic nutrients. Protozoa, including free-living amoeba (FLA), are known to be among the first microorganisms capable of colonizing harsh environments. In the present study, the presence of FLA has been evaluated in the Tajogaite Volcano deposits. Samples of the tephra were collected and incubated at 26 °C on 2% non-nutrient agar plates with a layer of heat-killed E. coli. Morphological features, as well as the DF3 region sequence of the 18S rDNA, confirmed the presence of a T4 genotype strain of Acanthamoeba. Thermotolerance and osmotolerance assays were used to evaluate the strain's pathogenic potential. This strain was considered thermotolerant but poorly osmotolerant. To the best of our knowledge, this is the first report of Acanthamoeba being isolated from a recently erupted volcano.

Enhancing sustainable energy production in the Canary Islands: Valorization of local biomass resources through thermochemical processes

Diverse biomass sources from the Canary Islands (vineyard, tomato plant residues, Canary pine needles and Pennisetum setaceum) were assessed due to their local abundance, availability, and low supply cost. Based on their physico-chemical properties, various thermochemical processes were conducted to assess their thermal degradation behaviour, using simultaneous thermal analysis, and their potential for energy production. The results indicate that while tomato plant biomass is unsuitable for thermochemical processes because of its elevated ash content and limited volatile matter, the other biomass sources show promising potential for pyrolysis and gasification, characterized by high fixed carbon content and reactivity. The yearly production of residual biomass in the Canary Islands was quantified at 87,253 tonnes. This biomass could generate an estimated 88.5 GWh of electricity annually. Considering that electricity consumption in the Canary Islands reached 8750 GWh in 2023, biomass-derived electricity could contribute approximately 1.0 % to the archipelago's energy needs. These findings highlight the significant role of local biomass resources in advancing renewable energy goals and reduce dependence on non-renewable sources, promoting a greener energy landscape for the Canary Islands.

The Potential of Wine Tourism in the Innovation Processes of Tourism Experiences in the Canary Islands—An Approach to the Case of the Canary Brand

The braided cord vineyard management system of the La Orotava Valley (Canary Islands, Spain) is a unique technique in the world that has been developed in the northern area of the island of Tenerife since the introduction of the first strains from Europe after the conquest of the Canary Islands and that synthesizes the unique wine cultural landscape of the territory. The future sustainability of this landscape seems to be inescapably linked to policies in favour of environmental, social and economic development, primarily through wine tourism. To do this, the methodology addresses the opinions of 16 in-depth interviews of key informants from the sector to understand this cultural landscape’s degree of use and enhancement. The results indicate significant progress in the revaluation and sustainability of the braided cord system (BCS) as part of the public–private strategy in search of its recognition as a BIC. Likewise, the winery sector recognizes the need to move towards a management model for the wine sector of the La Orotava Valley, where wine tourism has a more significant role, that seems to be closed based on the projects and initiatives under development.

Drugie życie silbo gomero – jak edukacja, turystyka i sztuka przyczyniły się do ocalenia gwizdanego języka z Gomery

THE SECOND LIFE OF SILBO GOMERO – THE CONTRIBUTION OF EDUCATION, TOURISM AND ART TO SAVING THE WHISTLED LANGUAGE OF THE ISLAND OF LA GOMERA Silbo gomero is a whistled language used by inhabitants of La Gomera (Canary Islands) and created before the arrival of Spanish settlers to overcome communication problems resulting from the deep ravines and narrow valleys that radiate through the island. The language, commonly used in the 17th, 18th and 19th centuries, declined in the 1950s–1980s due to economic migration, the growth of tourism and technological developments e.g. the telephone. Since the language was endangered in the late 1990s, revitalization efforts were generated at both community and governmental level. Nowadays, tourism is not a threat to silbo gomero; it’s seen as a great opportunity and as a generator of both employment and income. Unlike other islands in the archipelago, La Gomera focuses on natural resource-based tourism and cultural tourism and silbo gomero seems to be an ideal magnet for tourists looking for something more than the beach and the sun.

Architecture Competitions as an Opportunity for Young Women Architects. The Case of the Competition for Rural Subsidised Housing and the Canarian Magüi González, 1981-85

The Spanish democratic transition (1975-1982) was a time when architecture competitions with open and anonymous participation gradually began to appear, a phenomenon that coincided with the progressive incorporation of women architects into the discipline. The first part of this article analyses the situation of these competitions by studying their repercussions in 16 Spanish professional architectural journals belonging to both consolidated and emerging Spanish Architects’ Associations. The participation of women architects is also analysed in order to assess whether these competitions were a source of professional opportunities for them. In the second section, the article studies the Competition for Architectural Solutions for Officially Subsidised Single-Family Housing in Rural Areas (1981-83), a nationwide call with the most significant participation of architecture professionals (more than 1.000) and with a notable number of selected proposals by women architects. This study shows that women architects working in peripheral areas of the Spanish territory had a special presence in this competition, with the Canary Islands being the most remarkable case, for both the good results of its female participants and its ultra-peripheral location. Among the participating women architects, Magüi González stands out for the quality of her proposal and for being the only female professional who eventually obtained a commission from this competition. Finally, the investigation focuses, from a compositional, constructive and design culture perspective, on González’s final built project: 30 dwellings in Juan Grande in Las Palmas de Gran Canaria (1983-85), which was, indeed, her opera prima and was eventually awarded an important regional architecture prize.

The governance of the water-energy nexus: Co-produced narratives to take stock and address energy dependencies of the urban water cycle in Atlantic Europe

Water and energy (WE) are key resources to support human well-being and are highly interconnected. Intensifying demands of both resources and increasing resource scarcity are exacerbating their interconnectedness and calling for the adoption of an integrated approach called “WE nexus”. This paper explores the barriers and opportunities to govern the WE nexus in the Urban Water Cycle (UWC), particularly, the energy dependencies of the water supply and sanitation services in Atlantic Europe, through the assessment of four contrasting and representative regions: Canary Islands (ES), Western Andalusia (ES), Alentejo (PT) and Brittany (FR). We applied a “Quantitative Story Telling (QST)” method to assess the discourses from 49 stakeholders from across the four regions on WE nexus challenges and opportunities in the UWC, and the evidence that exists on them. The result is a pluralistic narrative incorporating the views of different stakeholders on what are the issues at stake and why, what needs to be done and how, and sustained by available data. The resulting narrative explores the formal aspects underpinning WE nexus governance in the UWC, but also informal rules linked to political economy. Our results revealed that WE nexus challenges are context-specific, however, there are important commonalities across regions and phases of the UWC value chain, suggesting that these are relevant at the Atlantic Europe scale. QST is not instrumental in directly inducing policy change or decision-making, but might be a valuable means for knowledge mobilization to question and enrich the quality of dominant discourses, and thus paving the road for action towards sustainability.

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.

Phenotypic response of a geographically expanding species, Scomber colias: Clues in the fish otolith shape

During the last decades, there has been a growing interest in the Atlantic chub mackerel, Scomber colias, owing to its northward expansion across the East Atlantic Ocean. This trend has been observed from regions of higher abundance off northwest Africa to the waters of the Atlantic Iberian and the Mediterranean Sea. Changes in abundance and spatial distribution of Atlantic chub mackerel have been previously studied and various theoretical models have been proposed to elucidate the changes in its abundance and biomass. However, within this fishing context, only a limited number of studies have attempted to understand how this species has responded at both the individual and population levels to the changing environmental conditions. The phenotypic variability of 1660 individuals of S. colias collected from the Canary Islands, Madeira, the Cantabrian Sea and the Central-Northern Mediterranean Sea was examined, with a specific focus on otolith shape. We identified six morphotypes classified into two groups and associated to the four analyzed regions. Despite of the occurrence of shared phenotypes in varying proportions among the different fishing grounds, this classification might be explained by the adaptation of certain morphotypes to specific environmental conditions and the migratory behavior of this species. The morphotypes M1-M5 were more abundant in the warmer waters of Madeira-Canary Islands region and M6 in the colder waters of Ligurian-Cantabrian. It is plausible that the former set may represent resident contingents, while morphotypes M2-M3 and M4 are likely to exhibit migratory behavior. Therefore, we suggest a complex metapopulation structure, where different contingents coexist.