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Avocado production has boomed worldwide in recent years, and Spain, including the Canary Islands, has been no exception. The number of avocado growers in the region has increased significantly as growers recognize the potential of this crop. However, several species of spider mites (Tetranychidae) pose a risk to this crop, with the genus Oligonychus being the most diverse and having the greatest economic impact. In particular, Oligonychus perseae (Tuttle, Baker and Abbatiello) has been reported as the one mainly responsible for the economic damage in major avocado-producing regions worldwide. In this paper, we aim to present an overview of the studies conducted and the measures implemented to mitigate the impact of O. perseae after its arrival in the Canary Islands. Our objective is to provide a detailed description of the current status of this pest (O. perseae), with special attention to its situation 17 years after its first appearance in avocado crops in the Canary Islands. In doing so, we aim to provide valuable insights and knowledge to understand and manage better the challenges posed by O. perseae in this region. [ABSTRACT FROM AUTHOR]

In this paper, we introduce LagunAR, a mobile outdoor Augmented Reality (AR) application for providing heritage information and 3D visualization on a city scale. The LagunAR application was developed to provide historical information about the city of La Laguna in the XVI century, when it was the main city in the Canary Islands. The application provides a reconstructed 3D model of the city at that time that is shown on a mobile phone over-imposed on the actual city using geolocation. The geolocated position is used also for providing information of several points of interest in the city. The paper describes the design and implementation of the application and details the optimization techniques that have been used to manage the full information of the city using a mobile phone as a sensor and visualization tool. We explain the application usability study carried out using a heuristic test; in addition it is probed by users in a qualitative user test developed as preliminary research. Results show that it is possible to develop a real-time application that shows the user a city-scale 3D model and also manages the information of the points of interest. [ABSTRACT FROM AUTHOR]

Seagrass and seaweed meadows hold a very important role in coastal and marine ecosystems. However, anthropogenic impacts pose risks to these delicate habitats. This paper analyses the multitemporal impact of the construction of the largest industrial port in the Canary Islands, near the Special Area of Conservation Natura 2000, on Cymodocea nodosa seagrass meadows (sebadales) of the South of Tenerife, in the locality of Granadilla (Canary Islands, Spain). Very-high-resolution WorldView-2 multispectral satellite data were used for the analysis. Specifically, three images were selected before, during, and after the construction of the port (2011, 2014, and 2022, correspondingly). Initially, advanced pre-processing of the images was performed, and then seabed maps were obtained using the machine learning K-Nearest Neighbors (KNN) supervised classification model, discriminating 12 different bottom types in Case-2 complex waters. The maps achieved high-quality metrics with Precision values of 85%, 81%, and 80%, recall of 76%, 77%, and 77%, and F1 scores of 80%, 79%, and 77% for 2011, 2014, and 2022, respectively. The results mainly show that the construction directly affected the seagrass and seaweed habitats. In particular, the impact of the port on the meadows of Cymodocea nodosa, Caulerpa prolifera, and maërl was assessed. The total maërl population was reduced by 1.9 km2 throughout the study area. However, the Cymodocea nodosa population was maintained at the cost of colonizing maërl areas. Furthermore, the port sedimented a total of 0.98 km2 of seabed, especially Cymodocea nodosa and maërl. In addition, it was observed that Caulerpa prolifera was established as a meadow at the entrance of the port, replacing part of the Cymodocea nodosa and maërl areas. As additional results, bathymetric maps were generated from satellite imagery with the Sigmoid model, and the presence of a submarine outfall was, as well, presented. [ABSTRACT FROM AUTHOR]

Simple Summary: The ladybird beetle fauna of the Canary Islands is quite specific due to the presence of a number of species that do not occur anywhere else (the so-called endemic species). However, many ladybirds recorded in the archipelago are relatively recent arrivals from various parts of the world, as shown by our previous surveys carried out in several of the Canary Islands, including Fuerteventura, Lanzarote, Gran Canaria, and El Hierro. In this paper, we analyze the ladybird fauna of La Palma, one of the western islands of the archipelago, based on our field survey and already published data. The survey resulted in the recording of 26 species, seven of which had not previously been recorded on La Palma, and two of these seven had not been recorded on any of the Canary Islands. Combining our data and literature reports gives a figure of at least 35 ladybird species recorded to date on La Palma. This is fewer than on the central islands of the Canary archipelago (Gran Canaria and Tenerife), but more than on the other four islands (Fuerteventura, Lanzarote, La Gomera, and El Hierro). This study confirms previous observations that the Canary Islands are often colonized by exotic ladybird species. This paper provides new data on the ladybird beetles (Coccinellidae) of La Palma, one of the western islands of the Canarian archipelago. The field survey of 54 study sites resulted in recording 2494 ladybird individuals belonging to 26 species. Seven of the species recorded were new to La Palma, including two, Harmonia quadripunctata (Pontoppidan) and Nephus reunioni (Fürsch), which were not registered so far on any of the Canary Islands. Novius conicollis (Korschefsky) is synonymized with N. cruentatus (Mulsant). Taking our survey and literature reports into account, a total of at least 35 species of Coccinellidae have so far been recorded on La Palma. This richness in species is lower compared to that of the central islands of the Canarian archipelago, Gran Canaria (42 species) and Tenerife (41 species), but higher than that of the remaining four islands (between 22 and 27 species). The detection of two alien species new to La Palma, Nephaspis bicolor Gordon and Nephus reunioni (Fürsch), confirms earlier observations that colonization of the Canary Islands by ladybird species of exotic origins seems to be a frequent phenomenon. [ABSTRACT FROM AUTHOR]

An intertidal sandstone reef, named barra de Las Canteras, protects the western coast of Las Palmas de Gran Canaria city (Canary Islands, Spain). The beach-reef system of Las Canteras constitutes one of the most valuable coastal geomorphological sites in the archipelago. Stratigraphic studies have identified the formation of the reef in the Last Interglacial (MIS 5e) in a coastal sedimentary paleo-environment. The rock structure is highly exposed to the Atlantic swell and consists mainly of a sandstone beachrock with a medium resistance to erosional processes. However, the historical and current erosion rates and the original extent of the reef are not known to date. This paper explores the geomorphological structure of the reef by combining a topo-bathymetric analysis (obtained by differential GPS, multibeam echosounder and hyperspectral sensor) and the analysis of geomorphological features on high-resolution images, obtained with a hyperspectral camera mounted on a UAV. The results provide a comprehensive, high-resolution image of the subaerial and submerged morphology of the reef. The structure reflects the distribution of erosional fronts and the existence of collapsing submarine blockfields and nearshore, uneroded, remnant reliefs. Detailed analysis of these features allows to estimate the probable original extent of the sandstone reef and to relate the erosional retreat processes to the sea-level dynamics during the Holocene. [ABSTRACT FROM AUTHOR]

This paper analyses the profile of individuals who decide to purchase a Sport Utility Vehicle (SUV) in a medium-sized isolated island system such as Tenerife Island. To achieve this objective, we used a survey conducted in 2017 to identify the characteristics of the individuals most likely to choose an SUV or another type of vehicle or be undecided. Subsequently, a discrete choice model was estimated to assess the probability that an individual chooses one of the three options as a function of their socio-economic characteristics, mobility routines, vehicle attributes and psychosocial traits. The results show the need to adopt energy policy measures related to vehicle choice, as they put the fulfilment of the decarbonization objectives for the energy transition in the Canary Islands at risk. Firstly, the authorities should carry out campaigns to achieve a more environmentally conscious behaviour by highlighting the higher consumption and emission levels of this type of vehicle. Secondly, subsidies for more efficient new vehicles and taxation should promote the purchase of low-emission vehicles to compensate for the greater willingness to pay of SUV buyers. In particular, purchase taxation should be linked to emission levels rather than only considering power, engine characteristics or labelling. [ABSTRACT FROM AUTHOR]

This paper presents a tidal current meter that is based on the inertial acceleration principle for offshore infrastructures in deep water. Focusing on the marine installations of the aquaculture industry, we studied the forces of tides at a depth of 15 m by measuring the acceleration. In addition, we used a commercial MEMS triaxial accelerometer to record the acceleration values. A prototype of the tidal measurement unit was developed and tested at a real offshore aquaculture infrastructure in Gran Canaria, which is one of the Canary Islands in the Atlantic Ocean. The proposed tidal measurement unit was used as a recorder to assess the complexity of measuring the frequency of tidal currents in the short (10 min), medium (one day) and long term (one week). The acquired data were studied in detail, in both the time and frequency domains, to determine the frequency of the forces that were involved. Finally, the complexity of the frequency measurements from the captured data was analyzed in terms of sampling ratio and recording duration, from the point of view of using our proposed measurement unit as an ultra-low-power embedded system. The proposed device was tested for more than 180 days using a lithium-ion battery. This working period was three times greater than the best alternative in the literature because of the ultra-low-power design of the on-board embedded system. The measurement accuracy error was lower than 1% and the resolution was 0.01 cm/s for the 0.8 m/s velocity scale. This performance was similar to the best Doppler solution that was found in the literature. [ABSTRACT FROM AUTHOR]

Occupational stress, as a negative facet, is a pervasive problem with significant implications for organizations, employees, welfare systems and health. The implementation of measurement tools that can capture the different organizational dimensions that determine stress in workers is part of the stress management and troubleshooting strategy that every company must manage daily. The aim of the present study was to adapt and validate the 25-item version of the ILO-WHO stress scale by Ivancevich and Matteson in the context of the Canary Islands of Spain. The tool assesses specific organizational dimensions of work-related stress determinants: organizational climate and structure, leader influence, cohesion, territory, technology and group support. An exploratory factor analysis (EFA) on a sample of 1510 Canary Islands workers was carried out. The results indicate that the job stress scale revealed adequate psychometric properties, construct validity and internal consistency (Cronbach's alpha = 0.972), and it can be profitably used to measure stress. At the end of the paper, theoretical and practical implications are discussed. [ABSTRACT FROM AUTHOR]

Simple Summary: Date stone beetles tunnel into the seeds of several palm species, where they establish brood galleries in which they spend their entire life cycle. Their larvae, which consume the seed's albumen, pupate and hatch in the seed, with multiple generations co-existing until all the seed's albumen has been consumed. Little is known about the initial tunneling and nature of the establishment of the brood galleries. Through experimentation with seeds of the Canary Islands Date Palm, this study shows that the beetles exhibited an overwhelming preference for a penetration at the grooved side. Behavioral observations showed that, in order to penetrate, the date stone beetle needs to be able to push its mandibles into the epicarp of the seed. The main thrust is generated by the hind legs which requires traction as provided by the groove. When tunneling, the mid legs function as a pivot, while the fore legs enable lateral control. When in the tunnel cavity the pair of mid legs act as wall anchors. Gustatory cues prevent the beetle from tunneling through to the other side. The nature of these gustatory cues remains unclear at this point and awaits future research. The cryptic spermatophagus date stone beetle (Coccotrypes dactyliperda Fabricius, 1801) tunnels into palm seeds for oviposition and subsequent establishment of brood galleries. Based on behavioral observations this paper describes the biomechanical and gustatory parameters that govern the initial excavation of the tunnels and the subsequent establishment of the galleries. When tunneling into Canary Islands Date Palm (Phoenix canariensis Chabaud, 1882) seeds, penetration principally occurs at the dorsal side of the seed, in particular the groove, which allows the beetle to gain the required traction. Tunneling is executed in a circular fashion with clockwise or counter-clockwise repositioning in approximately one-eighth to one-quarter turns. Biomechanically, the three pairs of legs provide thrust (hind legs), pivoting (mid legs), and lateral control (fore legs). Gustatory cues, the nature of which remains unclear at this point, prevent the beetle from tunneling through to the other side. [ABSTRACT FROM AUTHOR]

Cumbre Vieja volcano, located in La Palma Island (Canary Islands, Spain), erupted on 19 September 2021. Some papers have been published in the past in which the tsunamis generated by a potential massive landslide due to a collapse of one of the volcano flanks are investigated. However, a potential slide of the lava flow down the island slope has not been considered yet. A numerical model has been applied to simulate the propagation of the tsunami generated by such slide and to assess its consequences in the near field (Canary Islands and west coast of Africa). The model provides maps of maximum wave heights and arrival times of the tsunami, as well as time series of water surface elevation at several selected locations. Since the volume involved in such potential slide is a priori not known, several values were tested and their effects compared. [ABSTRACT FROM AUTHOR]