Browsing by Author "Florencio, Margarita"
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- Annotated checklist of aquatic beetles (Coleoptera) and true bugs (Heteroptera) in the Azores Islands : new records and corrections of colonization statusPublication . Lamelas-López, Lucas; Raposeiro, Pedro M.; Borges, Paulo A. V.; Florencio, MargaritaIn comparison with other Macaronesian archipelagos, Azorean freshwater macroinvertebrates are characterized by a smaller list of species at the archipelago regional scale. Although knowledge of the freshwater fauna of the Azores has improved in recent years through the implementation of the "Water Framework Directive", we are still far from having a complete inventory and even further from knowing the precise distribution and biology of each species. The lack of knowledge about Azorean freshwater species is coupled with the vulnerability of their habitats to anthropogenic disturbances and the introduction of non-native species. In contributing to overcome Wallacean and Hutchinsonian biodiversity shortfalls, we here provide expanded knowledge on the distribution and biology of the freshwater species of Coleoptera and Heteroptera in the Azores. We compile data from various fieldwork performed between 2006 and 2014, encompassing four islands in the archipelago. We detected new records of two aquatic Heteroptera species (belonging to the families Corixidae and Notonectidae) and six of aquatic Coleoptera (belonging to the families Dytiscidae, Gyrinidae, Hydrophilidae and Hydraenidae) in these islands, and also a new record (Enochrus fuscipennis) for the Azorean archipelago. We also suggest that the introduced colonization status of three Coleoptera species of the family Hydrophilidae should be reformulated as possibly native, with implications for conservation.
- Arthropod assemblage homogenization in oceanic islands: The role of indigenous and exotic species under landscape disturbancePublication . Florencio, Margarita; Cardoso, Pedro; Lobo, Jorge M.; Azevedo, Eduardo B.; Borges, Paulo A. V.Human landscape disturbance can drive the degradation of natural environments, thereby contributing to indigenous (endemic and native nonendemic) species extinctions, facilitating the establishment of exotic species and ultimately resulting in more similar species compositions over time and space. We assessed whether similarities in epigean arthropod assemblages differ between indigenous and exotic species in an oceanic archipelago, and we also examined whether such assemblage similarities depend on the most dominant species, the island, the type of habitat, the degree of landscape disturbance or local environmental variables.
- Biodiversity Patterns of Macroinvertebrate Assemblages in Natural and Artificial Lentic Waters on an Oceanic IslandPublication . Lamelas-López, Lucas; Borges, Paulo A. V.; Serrano, Laura; Gonçalves, Vitor; Florencio, MargaritaThe Azorean islands have been historically affected by human activities, mainly due to the combined effects of habitat degradation and fragmentation, and the introduction of exotic species. We here aim to analyze the role of environmental characteristics and spatial descriptors in supporting regional biodiversity of macroinvertebrates by considering natural ponds and artificial tanks. After the monthly variation of macroinvertebrate assemblages was assessed in three temporary and two permanent ponds in the Azorean island of Terceira during a complete inundation-desiccation annual cycle, the assemblage differences of 12 ponds (three temporary and nine permanent ponds) and 8 closely-located artificial tanks were analyzed across a range of landscape disturbances. Macroinvertebrate assemblages were found to differ according to hydroperiod and sampled months. Although the former explained the highest variance, macroinvertebrate differentiation by hydroperiod was also dependent on the study month. Our results also revealed a consistent monthly pattern of species replacement. However, the contribution of nestedness to the macroinvertebrate β-diversity was notable when temporary ponds were close to desiccation, probably indicating a deterministic loss of species due to the impoverished water conditions of the ponds facing desiccation. When the macroinvertebrate assemblages were analyzed in relation to physico-chemical variations and spatial descriptors, the artificial tanks were not clearly segregated from the natural ponds, and only differentiated by pH differences. In contrast, those natural ponds exhibiting high concentrations of total phosphorous (likely signs of anthropization) also discriminated the ordination of ponds in a distance-based redundancy analysis, and showed impoverished assemblages in comparison with well-preserved ponds. The macroinvertebrate assemblages of the natural ponds showed a significant spatial pattern, but this spatial influence was not significant when tanks and ponds were considered together. Our results suggest that tanks may act as possible reservoirs of biodiversity during the desiccation period of temporary ponds, but are unable to establish successful populations. These fishless permanent tanks can complement the conservation of a biodiversity that is largely maintained by the pristine high-altitude natural ponds. The establishment of a guideline for conservation management that also considers the artificial tanks is necessary to benefit the local and regional Azorean macroinvertebrate diversity.
- The colonisation of exotic species does not have to trigger faunal homogenisation : lessons from the assembly patterns of arthropods on oceanic islandsPublication . Florencio, Margarita; Lobo, Jorge M.; Cardoso, Pedro; Almeida-Neto, Mário; Borges, Paulo A. V.Human-caused disturbances can lead to the extinction of indigenous (endemic and native) species, while facilitating and increasing the colonisation of exotic species; this increase can, in turn, promote the similarity of species compositions between sites if human-disturbed sites are consistently invaded by a regionally species-poor pool of exotic species. In this study, we analysed the extent to which epigean arthropod assemblages of four islands of the Azorean archipelago are characterised by nestedness according to a habitat-altered gradient. The degree of nestedness represents the extent to which less ubiquitous species occur in subsets of sites occupied by the more widespread species, resulting in an ordered loss/gain of species across environmental or ecological gradients. A predictable loss of species across communities while maintaining others may lead to more similar communities (i.e. lower beta-diversity). In contrast, anti-nestedness occurs when different species tend to occupy distinct sites, thus characterising a replacement of species across such gradients. Our results showed that an increase in exotic species does not promote assemblage homogenisation at the habitat level. On the contrary, exotic species were revealed as habitat specialists that constitute new and well-differentiated assemblages, even increasing the species compositional heterogeneity within human-altered landscapes. Therefore, contrary to expectations, our results show that both indigenous and exotic species established idiosyncratic assemblages within habitats and islands. We suggest that both the historical extinction of indigenous species in disturbed habitats and the habitat-specialised character of some exotic invasions have contributed to the construction of current assemblages.
- Cómo la Macaronesia ha influido en nuestra perspectiva sobre los ecosistemas insularesPublication . Santos, Ana M. C.; Florencio, Margarita; Nogué, Sandra; Patiño, Jairo; Traveset, Anna; Borges, Paulo A. V.Actualmente el estudio de los ecosistemas insulares está pasando por un momento de constantes avances, siendo muchas de las nuevas y relevantes aportaciones fruto de estudios desarrollados en la Macaronesia (Azores, Canarias, Cabo Verde y Madeira). Ésta ha sido la mayor motivación para que el IBIG (Island Biology Interest Group – grupo de interés especial dentro de la AEET y de la SPECO) organizara un simposio dedicado a la Macaronesia, dentro del congreso internacional “Island Biology 2016 – II International Conference on Island Evolution, Ecology and Conservation”, realizado entre los días 18 y 22 de Julio, en Angra do Heroismo (isla Terceira, Azores), Portugal. El objetivo principal del simposio ha sido presentar una visión general de la investigación pasada y presente desarrollada en la región Macaronésica, colocándola en el contexto general de la biogeografía de islas. [...].
- Larval development and growth ratios of Odonata of the AzoresPublication . Lamelas López, Lucas; Florencio, Margarita; Borges, Paulo A. V.; Cordero-Rivera, AdolfoTo fully understand odonate life cycles, it is vital to analyse the patterns of larval growth, which are tightly associated with variations in environmental factors. However, the identification of larval instars is often difficult, especially for early development stages. We hypothesise that pond hydroperiod influences odonate larval growth, and test this idea with novel information about the environmental characteristics of 12 study ponds in Terceira Island (Azores). This study, which represents the first analysis of larval development of Odonata in the Azores, involved determining the instars of development and growth ratios. We measured the morphological characteristics of 898 Odonata larvae, and found that they significantly differed between temporary and permanent ponds. To estimate the larval instars, we used two methods: frequency distribution methods and correlation diagrams between body characteristics. The first method was the most effective, allowing the estimation of 17 instars for Anax imperator, 13 for Sympetrum fonscolombii and 10 for Ischnura hastata, as well as growth ratios between instars for head width, total length, abdomen length, wings and antenna length. Our results also suggest that a combination of the two methods is the most appropriate strategy for estimating the number of instars and growth ratios during larval development.
- Macaronesia as a Fruitful Arena for Ecology, Evolution, and Conservation BiologyPublication . Florencio, Margarita; Patiño, Jairo; Nogué, Sandra; Traveset, Anna; Borges, Paulo A. V.; Schaefer, Hanno; Amorim, Isabel R.; Arnedo, Miquel A.; Ávila, Sérgio P.; Cardoso, Pedro; Nascimento, Lea; Fernández-Palacios, José María; Gabriel, Sofia I.; Gil, Artur José Freire; Gonçalves, Vitor; Haroun, Ricardo J.; Illera, Juan Carlos; López-Darias, Marta; Martínez, Alejandro; Martins, Gustavo M.; Neto, Ana I.; Nogales, Manuel; Oromí, Pedro; Rando, Juan Carlos; Raposeiro, Pedro M.; Rigal, François; Romeiras, Maria M.; Silva, Luís; Valido, Alfredo; Vanderpoorten, Alain; Vasconcelos, Raquel; Santos, Ana M. C.Research in Macaronesia has led to substantial advances in ecology, evolution and conservation biology. We review the scientific developments achieved in this region, and outline promising research avenues enhancing conservation. Some of these discoveries indicate that the Macaronesian flora and fauna are composed of rather young lineages, not Tertiary relicts, predominantly of European origin. Macaronesia also seems to be an important source region for back-colonisation of continental fringe regions on both sides of the Atlantic. This group of archipelagos (Azores, Madeira, Selvagens, Canary Islands, and Cabo Verde) has been crucial to learn about the particularities of macroecological patterns and interaction networks on islands, providing evidence for the development of the General Dynamic Model of oceanic island biogeography and subsequent updates. However, in addition to exceptionally high richness of endemic species, Macaronesia is also home to a growing number of threatened species, along with invasive alien plants and animals. Several innovative conservation and management actions are in place to protect its biodiversity from these and other drivers of global change. The Macaronesian Islands are a well-suited field of study for island ecology and evolution research, mostly due to its special geological layout with 40 islands grouped within five archipelagos differing in geological age, climate and isolation. A large amount of data is now available for several groups of organisms on and around many of these islands. However, continued efforts should be made toward compiling new information on their biodiversity, to pursue various fruitful research avenues and develop appropriate conservation management tools.
- Perspectives and progress of ecology and conservation science in the Azores: the possible contribution of Artificial IntelligencePublication . Borges, Paulo A. V.; Cardoso, Pedro; Guerreiro, Orlando; Rigal, François; Florencio, Margarita; Amorim, Isabel R.; Borda-de-Água, Luís; Cascalho, José Manuel; Ferreira, MiguelThere is an urgent need of new methodologies in ecological and conservation science to deal with increasingly complex problems. We introduce four emerging research areas in ecology in which Artificial Intelligence may be explored as a tool to tackle unsolved issues in island ecosystems: (1) modeling abundance of plant and animal species in space and time; (2) modeling spread of invasive species; (3) estimating species richness based on incomplete sampling and (4) modeling speciation and diversification in insular habitats.
- The role of plant fidelity and land-use changes on island exotic and indigenous canopy spiders at local and regional scalesPublication . Florencio, Margarita; Rigal, François; Borges, Paulo A. V.; Cardoso, Pedro; Santos, Ana C.; Lobo, Jorge M.Understanding the processes that lead to successful invasions is essential for the management of exotic species. We aimed to assess the comparative relevance of habitat (both at local and at regional scale) and plant features on the species richness of local canopy spiders of both indigenous and exotic species. In an oceanic island, Azores archipelago, we collected spiders in 97 transects belonging to four habitat types according to the degree of habitat disturbance, four types of plants with different colonisation origin (indigenous vs. exotic), and four types of plants according to the complexity of the vegetation structure. Generalised linear mixed models and linear regressions were performed separately for indigenous and exotic species at the local and regional landscape scales. At the local scale, habitat and plant origin explained the variation in the species richness of indigenous spiders, whereas exotic spider richness was poorly correlated to habitat and plant structure. The surrounding landscape matrix substantially affected indigenous spiders, but did not affect exotic spiders, with the exception of the negative effect exerted by native forests on the richness of exotic species. Our results revealed that the local effect of habitat type, plant origin and plant structure explain variations in the species richness observed at a regional scale. These results shed light on the mechanistic processes behind the role of habitat types in invasions, i.e., plant fidelity and plant structure are revealed as key factors, suggesting that native forests may act as physical barriers to the colonisation of exotic spiders.