Browsing by Author "Furtado, Miguel"
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- Conservação dos vertebrados terrestres na ilha de Santa MariaPublication . Medeiros, Fátima; Mântua, Pedro; Portela, Nuno; Furtado, Miguel; Magalhães, Bruno; Teixeira, Balbina; Fonseca, AméliaA ilha de Santa Maria é a mais antiga dos Açores apresentando extensas formações de origem sedimentar (com mais de 8 milhões de anos) onde se podem encontrar fósseis marinhos. A região Ocidental aplanada, baixa, com solos argilosos e clima seco contrasta com a região Oriental, acidentada e sujeita à formação de nuvens e de precipitação elevada. Estas condições, propícias à sobrevivência de espécies da flora e da fauna com características e preferências bastante diversas, contribuem para a manutenção de uma biodiversidade muito particular. [...]. Assim, há que mitigar a perturbação antrópica e contribuir para manter o valor natural da ilha de Santa Maria por intermédio de acções de planeamento e fiscalização, designadamente: a) gerir eventuais alterações paisagísticas de modo a manter a diversidade de habitats naturais actuais; b) minimizar os impactes ambientais potencialmente perturbadores que poderão resultar destas modificações; c) restringir as actividades humanas nas proximidades de colónias de vertebrados ameaçados; d) gerir o acesso do homem nas proximidades de áreas de descanso e nidificação de aves migratórias; e) evitar a pesca excessiva de cefalópodes, de peixes e de crustáceos - elementos principais da dieta de várias espécies de aves marinhas; f) contribuir para a diminuição do uso de pesticidas e fertilizantes por parte dos agricultores, de modo a manter a sustentabilidade dos ecossistemas terrestres e marinhos; g) incentivar a utilização de combustíveis menos poluentes nos transportes marítimos.
- Potencial nutricional de macroalgas marinhas dos Açores. Determinação do teor de proteína.Publication . Furtado, Miguel; Paiva, Lisete S.; Lima, Elisabete M. C.; Baptista, José A. B.; Patarra, Rita F.; Neto, Ana I.
- Shell variation in Patellid limpets: scales of spatial variabilityPublication . Martins, Gustavo M.; Faria, João; Furtado, Miguel; Enes, Manuel; Neto, Ana I.Species o f the genera Patella generally display a high degree of shell variation, which is thought to be an adaptation to environmental conditions. The present work examines the variation in the morphometry of the two patellid limpets present in the Azores (Patella candei and P. aspera) at multiple spatial scales. Individuals of both patellid species were collected on two sites in each of the nine islands of the Azores. All individuals were measured to estimate base ellipticity, base eccentricity, conicity and cone eccentricity. Shell variation in P. candei was consistent among groups of islands (eastern, central, western) but there was significant variation in shell morphometry at the scales of islands and sites. Components of variation showed that a substantial proportion of variation was associated with the scale of individuais. Shell variation in P. aspera was consistent at the scale of island groups and islands but there was significant variation among sites. Analysis of the components of variability showed that variability in shell morphometrv was mostly associated with differences among individuais. Overall, these results suggest that variation in shell morphometry in the two patellid is not influenced by large scale processes as would be expected given that P. candei and P. aspera both have a pelagic Iarvae. In addition, this study suggests that shell variation in these species is likely to be a result of an adaptation to local conditions (e.g. microhabitats).
- Shells of Patella aspera as 'islands' for epibiontsPublication . Martins, Gustavo M.; Faria, João; Furtado, Miguel; Neto, Ana I.In this study we examined the epibiont assemblage on shells of the living limpet Patella aspera. Limpets were collected at two sites at each of the nine islands of the Azores, totalling 707 individuals examined. Shells were measured and all the epibiota identified to the lowest taxonomic resolution possible. 190 taxa were recorded, of which 97% were algae, including 17 new records for the Azores. Only five shells were devoid of fouling organisms. The assemblage was dominated by a few algal taxa, whereas the majority of species occurred on less than 10% of the shells. A significant and positive relationship was generally found between basibiont size (shell length) and epibiota richness. The strength (slope) of the relationship, however, varied between islands and sites. These results suggest that a range of processes operating at multiple spatial scales influenced epibiont assemblages. Many features identified in these assemblages resemble, in many ways, those examined in island biogeography, suggesting that basibionts may be considered as 'islands' and may provide a suitable model system to test ecological hypotheses about ecosystems that are not so amenable to experimentation.
- Shells of the limpet Patella aspera as habitat for epibiontsPublication . Faria, João; Martins, Gustavo M.; Furtado, Miguel; Neto, Ana I.Although limpets can control the abund ance and distribution of algae and other organisms, their shells can offer a refuge for the establishment of diverse assemblage that would otherwise be excluded. In this study, we make a preliminary analysis of the epibiota growing on shells of the limpet Patella aspern. Individuals of P. aspera were collected in all islands of the Azores and the biota on their shells was identified and quantified to species leveli. A total of 144 species was identified. The composition of the epibiota assemblage varied among islands and among locations within islands. There was also significant variation in epibiota richness at the scale of locations, but not at the scale of islands. A positive and highly significant correlation was also found between epibiota richness and shell length. This study adds to the literature by showing that the shells of P. aspern, an over-exploited species in the Azores, support a very rich community of algae and invertebrates and that this is controlled by processes operating at multiple spatial scales ranging from metres (among individuals) to 100's of kilometers (among islands).
- The surplus value of Azorean macroalgae as health-promoting food. Protein, fiber, carbohydrates, lipids and vitamins determinationPublication . Lima, Elisabete; Furtado, Miguel; Garcia, Ismael G.; Paiva, Lisete S.; Baptista, José; Patarra, Rita F.; Neto, Ana I.Seaweeds are traditionally used in animal nutrition supplement and have also been an important human dietary component. In addition to their value as a human food supplement, seaweeds may also contribute as a functional o r health-promoting food to prevent some of the most degenerative diseases ofthe industrial countries. Over the past few decades, the consumption of seaweed products’ has increased in European countries. Currently, approxirnately 15-20 edible algae strains are being commonly marketed for consumption in Europe. In the archipelago of the Azores (Portugal), the consumption o f seaweeds is widespread and accepted as a common practice in some of the islands. Being isolated in the middle of the Atlantic Ocean and taking into account the low pollution levels of seawater in the region, the Azores Islands have become a very promising location as a natural resource for marine macroalgae with potential for providing new ingredients of so-called functional or health-promoting foods. In the present investigation we evaluate the crude protein and crude fiber content offive selected macroalgae (Chaetomorpha linum and Codium adhaerens, Chlorophyta; Cystoseira humilis, Padina pavonica and Sargassum cymosum, Phaeophyta) collected in the littoral zone o f Sao Miguel Island (Azores). Protein content, determined by Kjeldahl method, varies greatly, from 2.86% to 18.48% of dry weight, in Padina pavonica and Codium adhaerens, respectively. Fiber content, determined by a modified Weende procedure, ranged between 31.02% and 69.10% of dry weight, in Codium adhaerens and Cystoseira humilis, respectively. Characterization and quantification of carbohydrates, lipids and vitamins were also performed in the referred species. The major chemical constituents of all the studied macroalgae revealed a dependence of the seasonal and environmental growth conditions (climate and habitats). Indeed algae can be considered as a magnificent bioreactor that is able to provide different types of compounds at different quantities depending mostly of the environmental conditions.
- Temperate facultative cleaner wrasses selectively remove ectoparasites from their client-fish in the AzoresPublication . Narvaez, Pauline; Furtado, Miguel; Neto, Ana I.; Moniz, Isadora; Azevedo, José M. N.; Soares, Marta S. C.Cleaner fishes are key contributors to the health of fish communities. However, much of the information in the literature refers to tropical systems, while fewer studies have examined the activity of cleaner fish inhabiting temperate ecosystems. Facultative cleaner fish are assumed to clean only during their juvenile phase, and have a broader diet than obligatory cleaner fish. Here, we focused on 2 facultative cleaner fish species, Coris julis and Thalassoma pavo, that live along the temperate coasts of the Azorean island of São Miguel. We found that these species focused their cleaning activities on relatively few species of clients, which supports the general idea that facultative cleaner fishes in temperate waters are less dependent on cleaning interactions than obligatory cleaner fishes in tropical waters. Both cleaner species were found to give more bites per host when inspecting larger clients, likely because the latter typically host more parasites. We found that C. julis consumed a greater diversity of food items, which included gnathiid larvae and fewer caligid copepods, compared to T. pavo where no ectoparasites were found. All cleaner fish that we collected after observations of cleaning had eaten gnathiid isopod larvae but not caligid copepods, even though caligid copepods were the most abundant ectoparasite found on the body of 7 selected fish species (including both client and non-client species), suggesting that both species selectively feed on gnathiid isopods. This study is the first to demonstrate that temperate facultative cleaner fish species actively and selectively inspect and remove ectoparasites from their client-fish species.