Browsing by Author "Oliveira, Paulo"
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- Invasive alien species in MacaronesiaPublication . Silva, Luís; Ojeda Land, Elizabeth; Rodriguez Luengo, Juan L.; Borges, Paulo A. V.; Oliveira, Paulo; Jardim, Roberto"[…]. As a consequence of all the geographic conditions and of historical events, the Canaries show the richest biodiversity. As an example, regarding endemic taxa, the Canaries have 524 vascular plants and 2768 arthropods (Martín Esquivel et al. 2005) while the Azores have 72 and 267, respectively (Borges et al. 2005) and the archipelagos of Madeira and Selvagens altogether have 154 and 979 (Borges et al. 2008a) respectively. It is well known that there are several plant genera in the Canaries with high numbers of species (Aeonium, Echium, Argyranthemum, Sonchus, etc.), which probably resulted from adaptive radiation, while in the Azores endemic plant species are found at a rate of one, and more rarely two or three species per genus. An intermediate situation is found in Madeira where genera Argyranthemum (Asteraceae) and Sinapidendron (Brassicaceae) show six endemic taxa (Jardim & Sequeira 2008). There are also other significant differences among the archipelagos. For instance, regarding vertebrate taxa, in the Azores there are no native species of reptiles and there are only two native mammal species, two bats, one of which endemic (Nyctalus azoreum), while there are several species in those groups both in the Canaries and in Madeira, namely the small lizard from Madeira (Teira dugesii, with four subspecies) or the giant lizards from La Gomera (Gallotia bravoana), El Hierro (G. simonyi), Tenerife (G. intermedia) and Gran Canaria (G. stehlini), among others. Thus, although there are similarities among the different regions, important geographic differences dictated that the native flora and fauna would show striking differences among the archipelagos. This is of considerable importance in order to understand what happened in each region, regarding the introduction of alien species. For instance, it is usually accepted that several species of Mediterranean distribution are considered as native in Madeira or in the Canaries, while the same species are considered as alien in the Azores."
- Terrestrial and freshwater biodiversity of the Madeira and Selvagens archipelagosPublication . Borges, Paulo A. V.; Abreu, Cristina; Aguiar, António F.; Carvalho, Palmira; Fontinha, Susana; Jardim, Roberto; Melo, Ireneia; Oliveira, Paulo; Sequeira, Miguel M.; Sérgio, Cecília; Serrano, Artur R. M.; Sim-Sim, Manuela; Vieira, PauloAs ilhas atlânticas dos Açores, Madeira, Selvagens, Canárias e Cabo Verde constituem uma das regiões da Europa mais ricas em diversidade de fungos, plantas e animais. Desde 2004 que a inventariação detalhada da diversidade destas ilhas tem sido um dos principais objectivos dos projectos ATLÂNTICO e BIONATURA (incluídos no projecto EU INTERREG IIIB). Este livro é a mais recente contribuição destes projectos, apresentando uma lista de todos os fungos, flora e fauna terrestre conhecida, incluindo a dulçaquícola, para dois arquipélagos atlânticos (Madeira e Selvagens). A lista abrange o arquipélago da Madeira, constituído por duas ilhas de maiores dimensões (Madeira e Porto Santo) e três pequenas, cujo conjunto constitui as Desertas (Ilhéu Chão, Deserta Grande e Bugio), e ainda o arquipélago das Selvagens, formado por duas pequenas ilhas (Selvagem Grande e Selvagem Pequena) e um ilhéu (Ilhéu de Fora).
- Using predictive models of species distribution to validate biodiversity data: case studies for Madeira IslandPublication . Jiménez-Valverde, Alberto; Hortal, Joaquín; Lobo, Jorge M.; Borges, Paulo A. V.; Abreu, Cristina; Aguiar, António F.; Azevedo, Eduardo B.; Boieiro, Mário; Fontinha, Susana; Jardim, Roberto; Oliveira, Paulo; Sérgio, Cecília; Serrano, Artur R. M.; Sim-Sim, Manuela; Nunes, DuarteOs modelos preditivos de distribuição de espécies são uma importante ferramenta para lidar com a falta de informação biogeográfica existente para a maior parte dos taxa. Com esta técnica, estabelece -se uma relação entre a variável dependente (presença/ausência de uma espécie) e um conjunto de variáveis potencialmente preditoras, e é criado um mapa com a probabilidade de presença da espécie para uma determinada área de interesse. Neste capítulo, é usado o programa Maxent para criar modelos de distribuição potencial de um conjunto seleccionado de espécies, e os resultados obtidos são discutidos com base no conhecimento de especialistas nessas espécies.
- Using taxonomically unbiased criteria to prioritize resource allocation for oceanic island species conservationPublication . Martín, José L.; Cardoso, Pedro; Arechavaleta, Manuel; Borges, Paulo A. V.; Faria, Bernardo F.; Abreu, Cristina; Aguiar, António F.; Carvalho, José A.; Costa, Ana C.; Cunha, Regina Tristão da; Fernandes, Francisco M.; Gabriel, Rosalina; Jardim, Roberto; Lobo, Carlos; Martins, António M. de Frias; Oliveira, Paulo; Rodrigues, Pedro; Silva, Luís; Teixeira, Dinarte; Amorim, Isabel R.; Homem, Nídia; Martins, Berta; Martins, Mónica; Pereira, EnésimaOceanic islands have been the grand stage of documented extinctions. In view of limited resources, efficient prioritization is crucial to avoid the extinction of taxa. This work lists the top 100 management priority species for the European archipelagos of the Macaronesian region (Azores, Madeira and the Canary Islands), taking into account both their protection priority and their management feasibility. Bryophytes, vascular plants, molluscs, arthropods and vertebrates were scored by species experts following two sets of criteria: (i) protection priority, including ecological value, singularity, public institutions’ management responsibilities and social value; (ii) management feasibility, including threats knowledge and control feasibility, external socio-economical support for management and biological recovery potential. Environmental managers weighted the same criteria according to their management importance. Final species scores were determined by the combination of both species valuation and criteria weighting. Vascular plants dominate the Top 100 list, followed by arthropods and vertebrates. The majority of listed taxa are endemic to one archipelago or even to a single island. The management feasibility criteria did not dictate that all taxa must be eminently endangered, as for most of the species it should be relatively easy to control threats. The main advantages of this process are the independent participation of scientists and conservation managers, the inclusion of criteria on both protection priority and management feasibility and the taxonomically unbiased nature of the process. This study provides a potentially useful biodiversity conservation tool for the Macaronesian archipelagos that could be readily implemented by the respective regional governments in future legislation.
- Valuing nature attributes by the tourists : are there socio-demographic differences?Publication . Oliveira, Paulo; Pereira, Pedro TelhadoThis research studies if there are different valuations of nature attributes due to different socio-demographic characteristics of the individuals. We use the case of the Natural Park of Madeira and the valuation of its different attributes by the tourists to test if there are differences due to gender, age, education, and nationality; we control by the duration and number of previous visits to the destination. We use a probit model to see how socio-demographic characteristics of the tourists and different aspects of the trip affect the valuation given to 24 aspects of the Park and its organization. We conclude that males tend to value 12 of the aspects less and do not value any more than females. Age does not seem to affect the way individuals value the different aspects; the exception is the WC, which is more valued by the elderly. More educated people tend to value less the organizational aspects of the park and the services provided. British visitors value more than tourists from other nationalities 10 of the 24 aspects of the Park, while Germans tend to value less the services provided by the Park.