Search Results (7)

The fragmentation and degradation of primary forests are serious threats to the long-term persistence not only of the tree species they comprise, but also of many organisms inhabiting them. The Canarian laurel forest, known as monteverde, is a highly threatened endemic forest of the Macaronesian region. Lichens are considered ideal bioindicators for assessing the effects of human disturbances on ecosystems and anticipating the response of other less sensitive organisms. However, no studies have used them as model organisms to analyze the conservation status of this primary forest in the Macaronesian region. In the present study, we analyzed several variables of the lichen biota of the Canarian laurel forest on the islands with the highest representation within this archipelago: La Gomera, La Palma, and Tenerife. We analyzed the species richness (and its relationship to island size with the real and potential vegetation areas of the laurel forest); the lichen diversity value, the number of shared and exclusive species on each of the islands as well as lichen functional traits as they have become important for evaluating the response of epiphytic lichens to environmental changes. The results indicate that there are signs of a potential extinction debt occurring in the diversity of epiphytic lichens in some areas. Furthermore, it has been observed that, despite the presence of some exclusive species on each island, the overall composition does not differ between them. Considering the functional traits of lichens, there are patterns that can provide information about the unique characteristics of the laurel forest of each of the studied islands. Full article

The endemic palm from the Canary Islands, Phoenix canariensis, is one of the most distinctive elements of the Canarian vegetation landscape, contributing to cultural, economic and environmental aspects. One of the main conservation problems facing this iconic palm is anthropogenic hybridization with other Phoenix species, particularly Phoenix dactylifera, which has been introduced extensively throughout its geographical range. Therefore, it is important to obtain a genetic tool that addresses different issues that may have an impact on the protection of P. canariensis, including ornamental applications and wild population conservation purposes. Our main goals were to detect a molecular tracer that could reliably distinguish between Phoenix canariensis and P. dactylifera in the Canary archipelago and to characterize the presence and extent of genetic hybridization events between the two species. We used 19 nuclear microsatellites and 1 chloroplast minisatellite set and analysed a large sample size (N = 433) of plants using both Bayesian methods and ordination techniques. Our data showed that a set of 13 nuclear markers revealed diagnostic alleles for P. canariensis, which were defined as the Canarian nuclear genotype (CNG). Moreover, P. canariensis exhibited an exclusive chlorotype of 266 bp that together with the GNC serve as an indicator of genetic purity in the Canarian palm. These markers are sufficient to detect any hybrid, even if it is not related to morphological differences. The occurrence of a considerable number of specimens with different degrees of hybridization is discussed in terms of the existence of different generations of hybrids and different types of crosses. Thus, the genetic tracers represent an invaluable tool to address any proposal for the genetic conservation of Phoenix canariensis. Full article

The mortality of birds resulting from collisions and electrocutions with overhead lines, such as power lines and phone lines, among others, has been implicated in the decline of various avian species globally. Specifically, overhead line collisions pose a significant threat to the conservation of the Canarian houbara bustard (Chlamydotis undulata fuertaventurae), an endangered subspecies endemic to the Canary Islands. This study centers on the postmortem findings of Canarian houbara bustards that have collided with overhead lines, providing insights into the post-collision outcomes for these birds. A complete standardized necropsy of nine Canarian houbara bustards revealed that trauma was the cause of death in all cases. The most notable gross lesions associated with trauma included bone fractures, soft tissue lacerations, hemorrhages, luxations, and hemocoelom. The inguinal area, chest, and wings were the body regions more frequently affected. A histopathology, immunohistochemistry, and entomology analysis confirmed that numerous birds survived the initial trauma. We concluded that when a houbara bustard collides with an overhead line, it frequently survives the initial trauma, with a survival time ranging from minutes to hours. The histopathology, immunohistochemistry, or entomologic analysis may be helpful to approximate the timing interval between trauma and death. Full article

Ramalina farinacea is a widely distributed epiphytic lichen from the Macaronesian archipelagos to Mediterranean and Boreal Europe. Previous studies have indicated a specific association between R. farinacea and Trebouxia microalgae species. Here, we examined the symbiotic interactions in this lichen and its closest allies (the so-called “R. farinacea group”) across ten biogeographic subregions, spanning diverse macroclimates, analyzing the climatic niche of the primary phycobionts, and discussing the specificity of these associations across the studied area. The most common phycobionts in the “R. farinacea group” were T. jamesii and T. lynnae, which showed a preference for continentality and insularity, respectively. The Canarian endemic R. alisiosae associated exclusively with T. lynnae, while the other Ramalina mycobionts interacted with both microalgae. The two phycobionts exhibited extensive niche overlap in an area encompassing Mediterranean, temperate Europe, and Macaronesian localities. However, T. jamesii occurred in more diverse climate types, whereas T. lynnae preferred warmer and more humid climates, often close to the sea, which could be related to its tolerance to salinity. With the geographical perspective gained in this study, it was possible to show how the association with different phycobionts may shape the ecological adaptation of lichen symbioses. Full article

The Canary Islands are considered a hotspot of biodiversity and have high levels of endemicity, including endemic reptile species. Nowadays, some invasive alien species of reptiles are proliferating with no control in different parts of the territory, creating a dangerous situation for the ecosystems of this archipelago. Despite the fact that the regional authorities have initiated actions to try to control the proliferation of invasive species, the problem has not been solved as it depends on sporadic sightings, and it is impossible to determine when these species appear. Since no studies for automatically identifying certain species of reptiles endemic to the Canary Islands have been found in the current state-of-the-art, from the Signals and Communications Department of the Las Palmas de Gran Canaria University (ULPGC), we consider the possibility of developing a detection system based on automatic species recognition using deep learning (DL) techniques. So this research conducts an initial identification study of some species of interest by implementing different neural network models based on transfer learning approaches. This study concludes with a comparison in which the best performance is achieved by integrating the EfficientNetV2B3 base model, which has a mean Accuracy of 98.75%. Full article

A retrospective survey for detecting the cetacean morbillivirus (CeMV) was carried out in beaked whales (BWs) stranded in the Canary Islands (1999–2017). CeMV is responsible for causing worldwide epizootic events with the highest mass die-offs in cetaceans, although the epidemic status of the Canarian Archipelago seems to be that of an endemic situation. A total of 319 tissue samples from 55 BWs (35 Cuvier’s BWs and 20 specimens belonging to the Mesoplodon genus) were subjected to the amplification of a fragment of the fusion protein (F) and/or phosphoprotein (P) genes of CeMV by means of one or more of three polymerase chain reactions (PCR). RNA integrity could not be demonstrated in samples from 11 animals. Positivity (dolphin morbillivirus strain (DMV)) was detected in the skin sample of only a subadult male Cuvier’s BW stranded in 2002, being the earliest confirmed occurrence of DMV in the Cuvier’s BW species. The obtained P gene sequence showed the closest relationship with other DMVs detected in a striped dolphin stranded in the Canary Islands in the same year. A phylogenetic analysis supports a previous hypothesis of a cross-species infection and the existence of the circulation of endemic DMV strains in the Atlantic Ocean similar to those later detected in the North-East Atlantic, the Mediterranean Sea and the South-West Pacific. Full article

Research on the fauna of beetles (Coleoptera) of the Canary Islands has a long tradition, which enables tracking changes in their species composition and arrival of new species. In this paper, we provide new faunistic data on the ladybird beetles (Coccinellidae) recorded on Gran Canaria, one of the central islands of the archipelago, and then analyze available information on the Gran Canarian ladybird fauna from geographical and historical points of view. The field survey resulted in recording 1402 ladybird individuals belonging to 30 species. Ten of these species were new to Gran Canaria and three of them, Chilocorus bipustulatus (Linnaeus), Nephus bisignatus (Boheman), and Nephus ulbrichi Fürsch, had not previously been reported to be on any of the islands of the Canarian archipelago. Tetrabrachys tinerfensis (Hodgson) is synonymized with T. deserticola (Wollaston). Our survey and literature reports allowed us to recognize 42 species of Coccinellidae so far recorded on Gran Canaria. Seventeen of them (40%) belonged to the Canarian endemic and subendemic species, and 21 (50%) were newcomers and presumed newcomers. Colonization of Gran Canaria and other islands of the archipelago by ladybird species of various origins seems to be a frequent phenomenon that may pose a threat to the unique communities of the native Canarian species. Full article