Browsing by Author "Lopes-Lima, Manuel"
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- Alarming decline of freshwater trigger species in western Mediterranean key biodiversity areasPublication . Nogueira, Joana Garrido; Sousa, Ronaldo; Benaissa, Hassan; De Knijf, Geert; Ferreira, Sónia; Ghamizi, Mohamed; Gonçalves, Duarte V.; Lansdown, Richard; Numa, Catherine; Prié, Vincent; Riccardi, Nicoletta; Seddon, Mary; UrbaÅ„ska, Maria; Valentini, Alice; Vikhrev, Ilya; Varandas, Simone; Teixeira, Amílcar; Lopes-Lima, Manuel; Nogueira J.G.Theidentification of key biodiversity areas (KBA) was initiated by the International Union for Conservation of Nature in 2004 to overcome taxonomic biases in the selection of important areas for conservation, including freshwater ecosystems. Since then, several KBAs have been identified mainly based on the presence of trigger species (i.e., species that trigger either the vulnerability and or the irreplaceability criterion and thus identify a site as a KBA). However, to our knowledge, many of these KBAs have not been validated. Therefore, classical surveys of the taxa used to identify freshwater KBAs (fishes, molluscs, odonates, and aquatic plants) were conducted in Douro (Iberian Peninsula) and Sebou (Morocco) River basins in the Mediterranean Biodiversity Hotspot. Environmental DNA analyses were undertaken in the Moroccan KBAs. There was a mismatch between the supposed and actual presence of trigger species. None of the trigger species were found in 43% and 50% of all KBAs surveyed in the Douro and Sebou basins, respectively. Shortcomings of freshwater KBA identification relate to flawed or lack of distribution data for trigger species. This situation results from a misleading initial identification of KBAs based on poor (or even inaccurate) ecological information or due to increased human disturbance between initial KBA identification and the present. To improve identification of future freshwater KBAs, we suggest selecting trigger species with a more conservative approach; use of local expert knowledge and digital data (to assess habitat quality, species distribution, and potential threats); consideration of the subcatchment when delineating KBAs boundaries; thoughtful consideration of terrestrial special areas for conservation limits; and periodic field validation.
- Assessment of a terrestrial protected area for the conservation of freshwater biodiversityPublication . Nogueira, Joana Garrido; Teixeira, Amílcar; Varandas, Simone; Lopes-Lima, Manuel; Sousa, RonaldoFreshwater ecosystems are essential to human well-being and most have high biodiversity. However, this biodiversity has been suffering severe declines owing to the expansion of human activities. Protected areas (PAs) are essential for biodiversity conservation and have proved to be successful in stopping species extirpation if managed properly. Unfortunately, they are usually focused on terrestrial biodiversity, leaving freshwater ecosystems aside. The main goal of this study was to determine the influence of a PA (Montesinho Natural Park (MNP), Portugal) on freshwater biodiversity. Aquatic macroinvertebrates and fishes were surveyed, and biodiversity (richness, abundance, Shannon-Wiener diversity, and Pielou's evenness) and water quality (IASPT) indices were calculated inside, at the periphery and outside the MNP. Results showed that the PA does not affect positively either water quality or the two faunal groups monitored. Macroinvertebrate communities were not influenced by the PA; however, the abundance of pearl mussel Margaritifera margaritifera was significantly higher and size was significantly lower inside the MNP. The richness and abundance of fish communities were significantly higher outside the MNP, except for trout Salmo trutta abundance which was higher inside the MNP. Given these results, the MNP does not guarantee the safeguard of overall aquatic biodiversity and habitats and we propose an extension of MNP to downstream areas in order to increase the number of species (mostly cyprinids) under legal protection. This work demonstrates that terrestrial PA planning and management should also consider aquatic biodiversity to achieve successful conservation.
- Bioecologia dos mexilhões de água doce (Unionidae) nos rios Sabor, Tua e Tâmega (Bacia do Douro, Portugal): principais ameaças e medidas de conservaçãoPublication . Teixeira, Amílcar; Varandas, Simone; Sousa, Ronaldo; Froufe, Elsa; Lopes-Lima, ManuelForam avaliadas as condições ambientais das populações de náiades (Mollusca, Bivalvia, Unionidae) em diferentes troços dos rios Tâmega, Tua e Sabor, na proximidade de grandes empreendimentos hidroelétricos em fase de construção. No verão dos anos 2010, 2011 e 2012 foi caracterizado o habitat e microhabitat disponível e usado pelas espécies Unio delphinus, Anodonta anatina e Potomida littoralis. Recorreu-se à metodologia do River Habitat Survey (RHS) para a avaliação do habitat aquático e ribeirinho. Para avaliação do microhabitat, foram realizados transectos paralelos (próximo das margens) e perpendiculares ao fluxo de água. Em cada microhabitat amostrado (0,25 m2) procedeu-se à medição das variáveis profundidade, substrato dominante, velocidade no leito e coluna de água, cobertura e distância à margem. Os unionídeos demonstraram uma distribuição espacial agregada em zonas específicas, tendo-se detetado densidades superiores na proximidade das margens e especialmente em braços laterais dos rios com fluxo permanente de água. Foram construídas curvas de preferência para cada espécie. Assim, Unio delphinus e Anodonta anatina colonizam preferencialmente pools com substrato fino, com núcleos populacionais situados entre raízes submersas, próximo de margens escavadas. Por sua vez, a espécie Potomida littoralis apresenta densidades superiores em zonas de maior corrente (riffles) e substrato mais grosseiro (seixos e pedras). Foram ainda realizadas experiências laboratoriais para determinação da íctiofauna hospedeira das 3 espécies de unionídeos, do qual se realça a afinidade quase exclusiva destas náiades com a fauna piscícola autóctone (nomeadamente com ciprinídeos endémicos e salmonídeos). Face às ameaças detetadas, caso da poluição, sedimentação e especialmente da regularização que conduzirá a uma redução do habitat disponível e da íctiofauna nativa nos rios Sabor, Tua e Tâmega, é fundamental a conservação de habitats e ecossistemas prioritários e a requalificação ambiental de troços degradados de modo a preservar as espécies de invertebrados e vertebrados autóctones fortemente ameaçadas
- Biology and conservation of freshwater bivalves: past, present and future perspectivesPublication . Lopes-Lima, Manuel; Teixeira, Amílcar; Froufe, Elsa; Lopes, Anabela; Varandas, Simone; Sousa, RonaldoFreshwater bivalves have been highly threatened by human activities, and recently their global decline has been causing conservational and social concern. In this paper, we review the most important research events in freshwater bivalve biology calling attention to the main scientific achievements. A great bias exists in the research effort, with much more information available for bivalve species belonging to the Unionida in comparison to other groups. The same is true for the origin of these studies, since the publishing pattern does not always correspond to the hotspots of biodiversity but is concentrated in the northern hemisphere mainly in North America, Europe and Russia, with regions such as Africa and Southeast Asia being quite understudied. We also summarize information about past, present and future perspectives concerning the most important research topics that include taxonomy, systematics, anatomy, physiology, ecology and conservation of freshwater bivalves. Finally, we introduce the articles published in this Hydrobiologia special issue related with the International Meeting on Biology and Conservation of Freshwater Bivalves held in 2012 in Bragança, Portugal.
- Biotic homogenization as a threat to native affiliate species: fish introductions dilute freshwater mussel’s host resourcesPublication . Douda, Karel; Lopes-Lima, Manuel; Hinzmann, Mariana; Machado, Jorge; Varandas, Simone; Teixeira, Amílcar; Ronaldo, SousaAim: The indirect consequences of biotic homogenization, the process of a gradual increase in the similarity of regional biotas driven by the combined effects of species invasions and extinctions, are still poorly understood. In this study, we aimed to assess the ability of a native affiliate species to maintain its host resources under the condition of biotic homogenization of host communities. Location: Central (Vltava River Basin, Czech Republic) and western (Douro River Basin, Portugal) Europe. Methods: We tested the ability of non-native species to serve as an alternative partner in local host–affiliate relationships. We used a European freshwater mussel, Anodonta anatina, which is considered to be a host generalist of native fish species, and compared the compatibility of its glochidia with native versus non-native fishes in two distinct European regions. Subsequently, we projected the obtained host compatibility data into the recent progress of biotic homogenization and estimated the degree of host dilution. Results: We found significant differences in the ability of A. anatina glochidia to parasitize the native and non-native fish species in both the central and peripheral parts of the mussel’s distribution range. As a result, the increasing presence of non-native species within fish communities across Europe likely significantly decreases the availability of the mussel’s host. Biotic homogenization of host communities may interfere with general life history traits (host specificity) of their local affiliate species. Main conclusions: This study demonstrates that the mixing of regional biotas may lead to an excessive loss of host availability even for host generalists, such as the freshwater mussel A. anatina, with potentially broad consequences for their population dynamics. Conservation strategies of endangered affiliate species need to incorporate the biogeographical context of host–affiliate relationships and particularly the consequences of biotic homogenization.
- Can invasive alien fish species act as effective hosts of native freshwater mussels (Unionidae) in Iberia?Publication . Teixeira, Amílcar; Dias, Ana Rita; Miranda, Fernando Jorge Veloso; Lopes-Lima, Manuel; Varandas, Simone; Froufe, Elsa; Filipe, Ana Filipa; Beja, Pedro; Sousa, RonaldoThe freshwater biodiversity of Mediterranean areas is severely threatened by several human activities, including habitat loss and fragmentation, river regulation, pollution, overexploitation, climate change and introduction of invasive alien species (IAS). These human disturbances drastically affect native fish and mussel populations and possibly conservation measures are needed to implement to revert major problems. Particularly at risk may be affiliate species such as freshwater mussels (Bivalvia, Unionoida) that have an obligatory parasitic phase of a short-term larval stage on fish host gills and fins. In Iberia, the identification of effective fish hosts for unionid species and the impact of IAS remain unclear. In this study, field and laboratorial studies were performed to assess the fish hosts for Anodonta anatina, Unio delphinus and Potomida littoralis. For in situ monitoring done in Douro basin (Northern Portugal), results showed an effective infestation for native (Luciobarbus bocagei, Squalius carolitertii, Squalius alburnoides and Pseudochondrostoma duriense) but also for non-native (Lepomis gibbosus, Alburnus alburnus, Gambusia holbrooki and Gobio lozanoi) fishes. The highest infestation rate and prevalence were observed for L. bocagei and S. carolitertii, but also for L. gibbosus. However, in laboratorial experiments significant differences were found. In fact, for U. delphinus and P. littoralis only native fishes (mainly endemic cyprinids) showed to be effective hosts, since viable juveniles were produced. A. anatina exhibited a more generalist behavior, with a wide range of native (endemic cyprinids of north and south Iberia) and non-native (Australoheros facetus, Oncorhynchus mykiss, Esox lucius, Phoxinus phoxinus, A. alburnus and G. lozanoi) fish host species. Overall, our results showed: 1) the importance of native fish species for the maintenance of a good conservation status of native unionids; 2) some invasive fish species can also function as hosts of A. anatina and 3) basic ecological data using field monitoring and laboratorial experiments are fundamental to design future conservation measures such as reproduction in captivity and propagation of threatened unionids.
- Caracterização ecológica das populações de mexilhão-de-rio (Margaritifera margaritifera l.) e de truta (Salmo trutta L.) na bacia hidrográfica do rio Tua (NE Portugal)Publication . Nogueira, Mónica Sofia Reis; Teixeira, Amílcar; Varandas, Simone; Lopes-Lima, Manuel; Hinzmann, Mariana; Machado, Jorge; Cortes, Rui M.V.Este estudo pretende caracterizar as condições ecológicas das populações de mexilhão-de-rio (Margaritifera margaritifera L.) e truta-de-rio (Salmo trutta L.) na bacia hidrográfica do rio Tua, nomeadamente nos rios Rabaçal e Tuela. A degradação ambiental (e.g. regularização, poluição) é um factor de regressão associado ao decréscimo da espécie M. margaritifera em Portugal que justifica a monitorização e avaliação do status desta náiade ameaçada e do seu hospedeiro obrigatório. Assim, no Verão de 2009 foi avaliada a qualidade da água e sedimentos, o habitat e microhabitat disponível e usado e determinados alguns parâmetros populacionais das duas espécies. Seleccionaram-se 2 troços em cada rio, com diferentes graus de perturbação, e aplicou-se a metodologia RHS (River Habitat Survey), complementada com uma análise mais detalhada do microhabitat. Através de transectos e snorkeling, foram mensuradas a profundidade, cobertura, substrato dominante e sub-dominante, e as velocidades da corrente na coluna de água e no leito. As regressões polinomiais elaboradas para as espécies e classes de tamanho consideradas demonstraram uma preferência similar entre a M. margaritifera e os alevins (0+) de truta, precisamente por habitats com alguma corrente, com pouca profundidade e com substrato tipicamente grosseiro (pedras) mas com interstícios ocupados por materiais finos (areias). Ambas as espécies apresentaram uma distribuição espacial não aleatória, concentrando-se principalmente em zonas com a cobertura propiciada pela vegetação ripícola. Relativamente à qualidade da água detectaram-se baixos teores em sais dissolvidos (condutividade < 50 µS.cm-1), nutrientes (e.g. N-Total <0,2 mg/L) e materiais particulados (POM <3 mg/L e PIM <0,01 mg/L). Foi detectada alguma concentração microbiana na água e sedimento indicadora de influência antrópica. Como medida de conservação da M. margaritifera nestes rios afigura-se essencial não só a monitorização da qualidade da água e do habitat, mas também a definição de planos de gestão e ordenamento adequados à especificidade destes rios.
- Complete mitochondrial genomes of the freshwater mussels Amblema plicata (Say, 1817), Pleurobema oviforme (Conrad, 1834), and Popenaias popeii (Lea, 1857) (Bivalvia: Unionidae: Ambleminae)Publication . Teiga-Teixeira, João; Froufe, Elsa; Gomes-dos-Santos, André; Bogan, Arthur E.; Karatayev, Alexander Y.; Burlakova, Lyubov E.; Aldridge, David C.; Bolotov, Ivan N.; Vikhrev, Ilya V.; Teixeira, Amílcar; Varandas, Simone; Zanatta, David T.; Lopes-Lima, ManuelFreshwater mussels are a critically imperiled group of mollusks that play key ecological roles and provide important services to humans. The Ambleminae is the only subfamily of these mussels, endemic to North America. Complete mitogenomes have only been sequenced for two of five tribes of the subfamily. Pleurobema oviforme, Amblema plicata, and Popenaias popeii each belong to tribes Pleurobemini, Amblemini, and Popenaidini, respectively, and have not had published mitogenomes. Thus, this study aims to present the complete mitogenomes for these species, to provide a phylogeny of the Ambleminae and confirm the gene arrangements with representation from each of its tribes. The newly sequenced mitogenomes range from 15,852 to 15,993 nucleotides, are composed of 13 PCGs, 22 tRNAs, and two rRNAs and all share the same (UF1) gene order.
- CONBI: Biodiversidade e conservação de bivalves – informação ecogeográfica, genética e fisiológica.Publication . Teixeira, Amílcar; Varandas, Simone; Sousa, Ronaldo; Froufe, Elsa; Lopes-Lima, ManuelUm dos grupos faunísticos mais ameaçados a nível mundial e em declínio global são os Unionidae (Mollusca), a maior de seis famílias de mexilhões de agua-doce. Para muitas espécies (independentemente do seu estatuto de conservação) no mundo inteiro, incluindo a Península Ibérica, são escassos, e em muitos casos inexistentes, os dados mais básicos sobre o seu ciclo de vida, dimensão e estrutura populacional, bem como a sua estrutura genética populacional. O presente projeto pretende preencher a lacuna de conhecimento sobre o estatuto da família Unionidae na Península Ibérica num contexto mais amplo da conservação da biodiversidade, sendo os principais objetivos: 1) compreender tanto a dinâmica atual das populações como a biogeografia histórica destes bivalves; 2) clarificar a sua diversidade taxonómica e afinidades filogenéticas; 3) compreender os mecanismos fundamentais da evolução do mtDNA dessas espécies; 4) descrever as suas principais características biológicas como a distribuição, estrutura populacional, época de reprodução, período larvar e peixes hospedeiros; 5) elucidar, do ponto de vista ecológico, os padrões de distribuição e os principais fatores bióticos e abióticos responsáveis pela sua distribuição. Sob uma perspetiva de gestão e conservação, pretende-se que os resultados obtidos possam ser usados para o desenvolvimento de estratégias futuras de conservação através da identificação de Unidades Evolutivas Significativas (ESUs) e de Unidades de Gestão (MUs). No presente trabalho são realçados aspetos da bioecologia de unionídeos no Nordeste Transmontano. E apresentada uma caracterização ecológica de populações das bacias do Sabor, Tua e Tâmega, assim como os ciclos de reprodução e peixes hospedeiros das espécies Anodonta anatina, Potomida littoralis e Unio delphinus.
- Conbiomics: the missing approach for the conservation of freshwater bivalvesPublication . Froufe, Elsa; Fonseca, Miguel M.; Teixeira, Amílcar; Varandas, Simone; Gonçalves, Duarte V.; Hinzmann, Mariana; Arenas-Arenas, Francisco José; Gan, Han Ming; Breton, Sophie; Prié, Vincent; Zieritz, Alexandra; Bogan, Arthur E.; Razgour, Orly; Vikhrev, Ilya V.; Bolotov, Ivan N.; Pfeiffer, John; Lopes-Lima, ManuelThe decline of freshwater biodiversity hás reached alarming proportions. The extinction rate of freshwater biodiversity is predicted to be five times faster than ali other groups of species. The Unionidae, being the largest of the freshwater bivalve families, is among the most endangered group in the world. They are important providers of aquatic ecosystem services and are characterized by an unusual pattem of mtDNA inheritance. However, phylogeny, population genetic structure and species-level diversity remains unclear for much of the group. With an experienced and well-qualified team, the present proposal aims to define the most important freshwater mussel taxa and most criticai áreas for conservation, at European and Global leveis, to inform the most relevant policy niakers. This will be achieved by integrating a genomics approach with available distribution data, in order to determine and map global species richness, phylogenetic diversity, and weighted endemism. This complementary approach will not only help conserve this vulnerable group but will offer wider benefits to freshwater ecosystems whose billions of people depend globally. Additionally, as these animals have an extraordinary unusual pattern of mtDNA inheritance, they will be used as model-taxa to study the evolution of mtDNA and life in general.