68 research outputs found

    Preliminary results on the daily and seasonal rhythms of cuttlefish Sepia officinalis (Linnaeus, 1758) locomotor activity in captivity

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    Cephalopods are considered as an alternate group for aquaculture species diversification [1,2], not only because they are a good food source (highly appreciated in some worldwide markets, e.g., Portugal, Spain, Italy and Asia) and have the potential to quickly reach a market size, but also because they are considered animal models in several fields of research [3–5], and it is expected that such models are progressively obtained from bioteriums instead of being captured from nature. Despite the recent advances in culture protocols of several cephalopod species [2], there is still little information available about the biological rhythms of cephalopods in captivity. In fact, to the best of our knowledge, there are only 4 published papers concerning this theme, and these are focused on octopus species [6–9]. This issue assumes increasing importance with the enforcement of EU welfare legislation (Directive 2010/63/EU), and this information is critical for the future update of Annex III (housing conditions) for cephalopods of that Directive, and for a future update of the Guidelines for the Care and Welfare of Cephalopods in Research [10]. If it is considered that the European cuttlefish Sepia officinalis (Linnaeus, 1758) may have, at the least, two different sleep‐like states [11], the importance of this study becomes even more evident.info:eu-repo/semantics/publishedVersio

    Control of zootechnology leads to improved Cuttlefish (Sepia officinalis, L.) reproduction performance up to pre-industrial levels

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    Cephalopods are gaining momentum as an alternate group for aquaculture species diversification, not only because they are a good food source (highly appreciated in some worldwide markets) but they also have the potential to quickly reach a market size. However, there are some bottlenecks impeding the transition of culture technology from the laboratory to industry. One is related to control over reproduction in captivity. The objective of the present experiment was to verify the effects of tanks with different bottom areas/volumes on the reproduction performance of S. officinalis breeding stocks, when sex ratios were controlled a priori; and the food cost associated with such performance when individuals are fed a natural frozen diet. One hundred and ninety two juvenile cuttlefish were used to compare three different round-shaped tanks: one type with 3000L volume and two types with 9000L volume (with differences in bottom areas and water column). Individuals had their sex and maturity stage determined to establish a sexual ratio of 2 female:1 male per tank and assure that cuttlefish were still immature. Biological data was collected during both growth and reproduction stages and until the death of all females in each tank. The experiment lasted nearly 300 days. Temperature differences between tank types were registered during both stages. The optimizing of rearing conditions has allowed for higher growth and a higher amount of cuttlefish available for breeding purposes. A total of 123,751 eggs (in 85 batches) was obtained during this experiment, which is a number that may meet a small scale cuttlefish commercial hatchery facility requirements. The present conditions contributed to a better and predictable reproduction performance in specific 9000L tanks, with values reaching pre-industrial numbers (approximate to 24,000 eggs/tank). Moreover, both the amount of eggs per batch and the overall quality of eggs has increased. Three of these 9000L tanks have an overall consumption of approximate to 38.64 Kg tank(-1), which translates in an investment in feed of approximate to 193 (sic) tank(-1), 8.40 (sic) per cuttlefish and an overall daily tank expense of 1.76 (sic) d(-1).info:eu-repo/semantics/publishedVersio

    Reproductive biology of Oxychilus(Atlantoxychilus) spectabilis (Milne-Edwards, 1885) (Gastropoda: Pulmonata) : a gametogenic approach

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    The taxonomic status and anatomy of Oxychilus (Atlantoxychilus) spectabilis (Milne-Edwards, 1885), an endemic land snail from Santa Maria Island, Azores, has been subject of detailed study, yet information about its life history is wanting. This study describes the reproductive cycle of O. (A.) spectabilis and assesses the validity of three morphometric shell parameters as maturation diagnostic characters. Our results indicate that individuals are reproductively more active from May to November. However, the availability of spermatozoa throughout the year and the residual values of mature oocytes during the remaining months seem to provide minimum conditions for reproduction all year round. The snail has a functional protandric tendency and gonadal maturation is initially triggered by photophase and after regulated by temperature. The positive correlation between gonadal maturation and morphometric shell characters indicate that these parameters might be a useful tool for the diagnosis of snail’s maturation

    Monitoring ground arthropods in maize and pasture fields of São Miguel and São Jorge Islands: IPM-Popillia Project.

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    ABSTRACT: The dataset presented here is the delivery of the European project “Integrated Pest Management of the Invasive Japanese Beetle, Popillia japonica (IPM-Popillia)”. This project aims to address the challenge of a new risk to plant health in Europe, the invasion of the Japanese beetle, Popillia japonica, and to provide an environmentally friendly IPM-Toolbox to control the pest in infested areas, protecting the agricultural systems and control this pest populations current in expansion across Europe. The present study targets to record, in maize and pasture fields of the Azores, ground arthropods with the potential to be used in futures Integrated Pest Management programs against P. japonica. A sampling program was conducted in two Islands (São Miguel and São Jorge) in the summer of 2022.info:eu-repo/semantics/publishedVersio

    Optical strain sensor based on FPI micro-cavities produced by the fiber fuse effect

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    In this work we present a cost effective strain sensor based on micro-cavities produced through the re-use of optical fibers destroyed by the catastrophic fuse effect. The strain sensor estimated sensitivity is 2.22 +/- 0.08 pm/mu epsilon. After the fuse effect, the damaged fiber becomes useless and, consequently, it is an economical solution for sensing proposes, when compared with the cavities produced using other complex methods. Also, the low thermal sensitivity is of great interest in several practical applications, allowing eluding cross-sensitivity with less instrumentation, and consequently less cost

    Monitoring Arthropods in maize and pasture fields in São Miguel and São Jorge Islands: IPM-Popillia Project

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    ABSTRACT: The dataset presented here is an achievement of the H2020 European project "Integrated Pest Management of the Invasive Japanese Beetle, Popillia japonica (IPM-Popillia)". This project addresses the challenge of a new risk to plant health in Europe, the invasion of the Japanese beetle, Popillia japonica (Newman, 1838) (Coleoptera, Rutelidae) and provides an environmentally friendly IPM Toolbox to control the expanding pest populations across Europe. This study aims to present the records of terrestrial arthropod diversity with a special focus on four groups belonging to Carabids and Staphylinid beetles (Coleoptera), Opiliones and Anisolabididae (Dermaptera), collected with the potential to be used as biocontrol agents against P. japonica in future Integrated Pest Management programmes. A thorough sampling programme was conducted in maize and pasture fields in two Islands of the Azores (São Miguel and São Jorge) in the summer of 2022.info:eu-repo/semantics/publishedVersio

    Sensors based on recycled optical fibers destroyed by the catastrophic fuse effect

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    In the last decades the fiber Bragg gratings (FBG) and Fabry-Perot Interferometer (FPI) micro cavities based sensors have become one of the most attractive optical fiber sensing technologies. However, its production requires a significant economical investment. We propose a cost effective solution based on micro cavity generated by the recycling of optical fibers destroyed through the catastrophic fuse effect. This technique considerably reduces the experimental complexity and the production costs. In this paper, the application of these sensors in the monitoring of several parameters, such as refractive index, pressure, strain and temperature is presented

    Descrição da biodiversidade terrestre dos Açores

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    Os Açores constituem um arquipélago de nove ilhas oceânicas isoladas, onde os organismos terrestres chegaram através do vento, do mar, noutros animais e, nos tempos históricos, com a ajuda humana. Este capítulo analisa de forma detalhada aquilo que se conhece sobre a biodiversidade terrestre dos Açores. Para tal analisámos os quatro grandes grupos de organismos listados no capítulo 4: Bryophyta (musgos, antocerotas e hepáticas), Pteridophyta e Spermatophyta (fetos e fanerogâmicas), Mollusca (lesmas e caracóis) e Arthropoda (centopeias, diplópodes, crustáceos, aranhas, ácaros, insectos, etc.). O número total de espécies e/ou subespécies dos Açores pertencentes aos quatro grupos de organismos acima referidos é de cerca de 3705 (3666 espécies e 224 subespécies). No entanto, adicionando outros grupos como os vertebrados (Chordata, Vertebrata), anelídeos (Annelida), nemátodos (Nematoda) e líquenes, aquele número sobe para 4487 espécies e/ou subspecies (4443 espécies e 232 subespécies). O número total de espécies e/ou subespécies endémicas dos Açores pertencentes aos Bryophyta, Pteridophyta, Spermatophyta, Mollusca e Arthropoda totaliza as 393 (384 espécies e 44 subespécies). Os filos animais são os mais diversos em taxa endémicos (Mollusca = 49; Arthropoda = 267), com cerca de 80 % dos endemismos dos Açores. Deve ser ainda de assinalar a elevada percentagem de endemismo nos caracóis e lesmas (Mollusca) terrestres dos Açores, com cerca de 44% de endemismo. As plantas vasculares possuem 68 endemismos e os briófitos 9. Usando um estimador não paramétrico, a estimativa conservadora da riqueza de taxa endémicos terrestres de briófitos, plantas vasculares, moluscos e artrópodes rondará 530 taxa, pelo que apenas 77% dos endemismos dos Açores serão conhecidos. Em apenas alguns géneros se verificou uma taxa de especiação elevada, na sua maior parte pertencentes aos filos Mollusca e Arthropoda. A maior parte das espécies de artrópodes e moluscos endémicos são conhecidas apenas de uma ilha, enquanto que, nas plantas, uma grande fracção das espécies ocorre na maioria das ilhas. A análise das proporções das várias categorias de colonização mostra que uma grande proporção da phanerofauna de artrópodes e da flora de plantas vasculares do arquipélago é constituída por espécies introduzidas. Deste modo, as invasões por espécies exóticas constituem um problema actual e terão impactos futuros na biodiversidade dos Açores, criando um padrão de uniformização da fauna e flora. Os Açores constituem o arquipélago da Macaronésia geologicamente mais recente, estando situado mais a norte. As suas nove ilhas isoladas no meio do oceano Atlântico possuem uma grande diversidade de histórias geológicas e constituem laboratórios ecológicos e evolutivos extraordinários. Torna-se cada vez mais importante um esforço adicional nos estudos de taxonomia e ecologia de comunidades que envolvam o estudo de grupos taxonómicos mal conhecidos (fungos, líquenes, muitos grupos de artrópodes) mas também a revisão taxonómica de muitas espécies de briófitos e plantas vasculares.ABSTRACT: The Azores is a remote oceanic archipelago of nine islands where the terrestrial organisms arrived by wind, on the sea, on other animals and on historical times by human assistance. This chapter highlights what we know about Azorean terrestrial biodiversity. Four important terrestrial taxonomic groups listed in Chapter 4 are analysed in detail: Bryophyta (mosses, liverworts), Pteridophyta and Spermatophyta (ferns and phanerogamics), Mollusca (slugs and snails) and Arthropoda (millipedes, centipedes, mites, spiders, insects, etc.). Currently the total number of terrestrial species and/or subspecies of the above mentioned organisms in the Azores is estimated of about 3705 (3666 species and 224 subspecies). However, if we add other groups like vertebrates (Chordata, Vertebrata), annelids (Annelida), nematodes (Nematoda) and lichens, this number reaches 4487 species and/or subspecies (4443 species and 232 subspecies). The total number of endemic species and/or subspecies from the Azores belonging to Bryophyta, Pteridophyta, Spermatophyta, Mollusca and Arthropod is about 393 (384 species and 44 subspecies). The animals Phyla are the most diverse in endemic taxa (Mollusca = 49; Arthropoda = 267), comprising about 80% of the Azorean endemics. The percentage of endemismo within Mollusca (44%) is remarkable. Vascular plants have 68 endemic species while bryophytes have 9 endemics. Using a non-parametric estimator we obtained a conservative estimate for endemic Azorean terrestrial vascular plants, bryophytes, molluscs and arthropods around 530 taxa, which mean that only about 77% have already been described. In only some genera there was a substantial inter and intra-island speciation, most cases occurring in Mollusca and Arthropoda. Most of the endemic arthropods and molluscs are known in only one island, whereas in plants a large proportion of species occur in most islands. Na analysis of the proportions of the colonization categories in arthropods and vascular plants shows that a major proportion of the species are introduced. Therefore, invasions of alien organisms are an actual and future environmental threat in the Azores, creating a pattern of biotic homogenization that is of great contemporary concern. The Azores is the northernmost and the most recent Macaronesian archipelago. The nine islands, isolated in the middle of the Atlantic, with different geological histories, are wonderful ecological and evolutionary laboratories. An additional effort on taxonomic and community-level research implies the detailed examination of poorly studied groups (fungi, lichens, many arthropod groups), but a revision of the taxonomic status of many bryophyte and vascular plants is also deeply needed

    Macroecological patterns of species distribution, composition and richness of the Azorean terrestrial biota

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    We investigate the macroecological patterns of the terrestrial biota of the Azorean archipelago, namely the species-range size distributions, the distance decay of similarity, and the island species–area relationship (ISAR). We use the most recent up-to-date checklists to describe the diversity at the island level for nine groups (Lichens, Fungi, Diatoms, Bryophytes, Vascular Plants, Nematodes, Molluscs, Arthropods, Vertebrates). The particularities of the Azorean biota result in some differences to the patterns commonly found in other oceanic archipelagos. Strikingly, bryophytes, molluscs and vertebrates show a bimodal species-range size distribution, and vascular plants a right unimodal distribution due the high numbers of widespread species. Such high compositional homogeneity between islands also results in non-significant or even negative decays of similarity with distance among islands for most groups. Dispersal ability, together with other particular characteristics of each taxon, also shapes these distributions, as well as the relationships between island species richness, and area and time. Strikingly, the degree of departure of the richness of the whole archipelago from the SAR of its constituent islands largely depends on the dispersal ability of each group. Comparative studies with other oceanic archipelagos of the globe are however needed to understand the biogeographical and evolutionary processes shaping the remarkably low diversity of the Azorean biota
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