Luís Fonseca - Academia.edu (original) (raw)
Papers by Luís Fonseca
Limnetica, 2017
First record of the tadpole shrimp Triops cancriformis (Lamarck,1801) (Crustacea: Branchiopoda: N... more First record of the tadpole shrimp Triops cancriformis (Lamarck,1801) (Crustacea: Branchiopoda: Notostraca) in Portugal Notostracan crustaceans identified as Triops cancriformis according to the presently accepted morphological criteria were recorded for the first time in Portugal in 2007. All previous records of Triops in Portugal belong to mauritanicus lineage species i.e. T. vicentinus or T. baeticus. A specimen purportedly belonging to T. cancriformis (Carvalho, 1944) has been re-identified by Machado in 2014 as T. baeticus after morphological examination. During 2007, hundreds of individuals of T. cancriformis were observed throughout the rice paddies on the northern margin of Sorraia River (Vale do Sorraia, Coruche). In the last 9 years, monthly checks during the rainy season have failed to record high population abundances and only a few specimens have been observed in the flooded tracks left by trucks and other heavy machinery on the elevated margins of the paddies. The low number of individuals observed in the latter years possibly results from changes of ecological conditions. Thus far, males of T. cancriformis have not been recorded, which may indicate that the observed population is either androdioecious or made of hermaphrodite or parthenogenetic populations. This situation contrasts with the other confirmed populations of this species in the Iberian Peninsula that are gonochoric. Parthenogenetic/hermaphrodite/androdioecious lineages, present in Northern and Central Europe, are considered to have derived from gonochoric Iberian populations in the Pleistocene which makes this finding all the more interesting in evolutionary terms. Has this population resulted from a recent recolonization from non-Iberian populations? Or has it derived directly from the assumed Iberian Pleistocene refuge? The potentially high dispersal abilities of Triops diapausing cysts and the possibility of hermaphrodite/parthenogenetic reproduction favour the 1st hypothesis of recolonization. Possible sources of individuals are (i) cysts attached to migratory birds arriving possibly from Southern France or Northern Italy and that are regularly seen feeding at these rice fields or ii) cysts unwittingly transported with the rice seeds used in the Vale do Sorraia. Both are in accordance with the assumption that nongonochoric reproductive mode confers a colonization advantage over gonochoric populations, which lack evidence of fast long distance dispersal ability. Future multilocus phylogenetic analysis is expected to clarify the origin of T. cancriformis found in the Sorraia's rice fields.
Limnetica, 1999
Lagoa da Sancha as part of an ecological characterisation of the Alentejo littoral lagoonal syste... more Lagoa da Sancha as part of an ecological characterisation of the Alentejo littoral lagoonal systems. Lagoa da Sancha is North of the locality of Sines, and spreads over an area of approximately 4 ha. It has an elongate shape along a N-S axis, and receives water from a hydrographic basin of approximately 37 km 2. The lagoon can be considered a system in which communication with the sea, which could provide its renewal, is naturally established only very seldom according to local fishermen (an inlet has existed only once in the past 25 years). Overwash is the main source of sea water. This is revealed by salinity values, always below 5‰ (oligohaline), except for summer values, when values, may reach 12%o (mesohaline) due to evaporation. Of the 69 invertebrate taxa found, 89.8% can be considered as continental and 8.7% of lagoonal affinities (i.e. lagoonal-continental). Only few groups were present throughout the year, with a constant presence of continental species (e.g. Daphnia sp, Herpetocypris reptans, Cloeon sp., Plea leachi, Berosus sp., Chironomidae). Anomopoda and Chironomidae were the dominant groups. Individuals of brackish lagoonal species were rare during the sampling period. Results show this benthic community is very similar to that of temporary lentic systems, where the taxa succession is erratic.
Este trabalhoque não é um artigo científico e por isso não segue a sua estruturareúne um conjunto... more Este trabalhoque não é um artigo científico e por isso não segue a sua estruturareúne um conjunto de opiniões de vários investigadores que se dedicam ao estudo das zonas costeiras. A todos se pediu que reflectissemcom base na sua experiência pessoal e profissionalsobre a gestão actual deste espaço, partindo da frase do artista plástico Carlos Augusto Ribeiro, que serve de título a este texto. Aqui se discute sobre populações e saberes tradicionais, obras de engenharia costeira, gestão de conflitos, destruição de ecossistemas e insustentabilidade, necessidade de cooperação e conhecimento multidisciplinar, novos modelos de gestão do litoral e de cidadania.
Reviews in Aquaculture, 2018
Polychaetes are marine annelid worms that can contribute to aquaculture diversification. Its cult... more Polychaetes are marine annelid worms that can contribute to aquaculture diversification. Its culture has been viable, and commercially attempted, but intensive production has progressed only in few countries around the world. In the countries with no production, marine polychaetes are imported or harvested. A strong and sustained research investment provided to a better understanding of the nutritional requirements and reproduction of some species. Recent studies showed new technical improvements, which can lead to an important progress in productivity and give a new impetus to the polychaete production. Some marine worm species were identified as good candidates for integrated multitrophic aquaculture. The development of cost‐effective aquaculture techniques for marine annelid worms is essential to ensure a balance between commercial interests and the preservation of ecosystems. The influence of polychaete aquaculture on the environment and vice versa raise important concerns relat...
Hydrology Research, 2015
We examined the variation of stygofauna composition collected in wells, along a gradient in groun... more We examined the variation of stygofauna composition collected in wells, along a gradient in groundwater salinity/conductivity in a coastal aquifer from southern Portugal. The studied coastal aquifer is considered vulnerable to salinization due to seawater intrusion, caused by overexploitation of the aquifer. Knowing the response of the stygofauna species to present levels of groundwater salinity makes it possible to understand and measure the effects of saltwater intrusion on stygofauna, rendering them potential bioindicators of this environmental pressure. Biotic and abiotic sampling was conducted in six shallow wells located in the fresh–saltwater interface of the Arade estuary along the salinity gradient established in the groundwater from the estuary to inland locations (microSiemens/cm). Groundwater salinity was highly correlated with taxa distribution. The stygobites Eucyclops hadjebensis and Acanthocyclops sensitivus, the cosmopolitan Megacyclops viridis and Cypria ophtalmica...
The importance of Santo André Lagoon (SW Portugal) for the conservation of biodiversity has been ... more The importance of Santo André Lagoon (SW Portugal) for the conservation of biodiversity has been recognized over the last few years (Ramsar, SPA, Natura 2000). This is well demonstrated by its inclusion, since 2000, in the Portuguese Network of Protected Areas (Reserva Natural das Lagoas de Santo André e Sancha). In this circumstance, birds clearly stand out. Its avifauna includes a significant number of migratory species and/or a high conservation value, being the main reason for its choice as a site for regular bird ringing campaigns for nearly 30 years. Due to their relevance, waterbird species deserve special attention from management rules established in this protected area. During 2005 and 2006 the presence of aquatic birds was monitored monthly in different sectors of the lagoon. The results, besides showing high abundances of several species, confirm the importance of the area for the coot (Fulica atra), at a national level. Also important is the regular occurrence of the re...
Scientia Marina, 2006
The importance of the market for polychaetes dramatically increased after the discovery of their ... more The importance of the market for polychaetes dramatically increased after the discovery of their potential as food in aquaculture. In Portugal, the gathering of polychaetes solely from natural populations is not sufficient to meet market demand, both as bait for sea anglers and as a food item in aquaculture. The requests for worms to polychaete dealers by Portuguese and Spanish seafarms have increased during recent years. Due to the lack of intensive culture of these worms in Portugal and the proximity of southern Spanish farms, a large component of imported polychaetes that arrive in Portugal at Lisbon Airport go directly to Spain by road. In 2002 and 2003 a total of 12,728,379 and 16,866,839 polychaetes respectively were imported to Europe via Lisbon Airport from China and the USA. In 2003 the imports from China and the USA realised 716,180 and 291,845 US dollars respectively. Two species were reported to have been imported in these years, namely the Korean blue ragworm Perinereis aibuhitensis and the American bloodworm Glycera dibranchiata. Imports of non-indigenous species, which are traded and sold alive, may increase the risk of accidental introduction into the wild. This is of special concern as Perinereis aibuhitensis has been successfully reared in captivity within the range of environmental conditions existing in the Ria Formosa coastal lagoon. Other risks associated with introduced species are the transport of foreign pathogens and other associated non-native organisms, which may act as carriers of disease.
Journal of Applied Ecology, 2006
Summary Predator conservation management requires detailed understanding of the ecological circum... more Summary Predator conservation management requires detailed understanding of the ecological circumstances associated with predation, especially that on economically valuable prey. We examined the mechanisms behind Bonelli's eagle Hieraaetus fasciatus predation on prey of domestic origin, using dietary data from 22 pairs breeding in south‐west Portugal (1992–2001) together with information on landscape composition and prey availability. Numerically, 42·7% (37·7% in biomass) of eagle prey comprised domestic species, about 70% of which were rural pigeons Columba livia and the remainder were racing pigeons Columba livia and domestic fowl Gallus gallus. Rabbits Oryctolagus cuniculus, red‐legged partridges Alectoris rufa and jays Garrulus glandarius were the most frequent wild prey (43·1%; 50·8% in biomass). This dietary pattern was remarkably stable over a decade, but within each year the intake of pigeons almost halved over the course of the breeding season. Landscape composition sig...
Brazilian Journal of Oceanography, 2011
The secondary productivity of reef epifauna is one of the least investigated aspects in artificia... more The secondary productivity of reef epifauna is one of the least investigated aspects in artificial reef research. During the first 12 months after the deployment of the Faro/Ancão (Algarve, Portugal) artificial reef, we assessed the effect of substratum orientation on the secondary production of epibenthos, using the Boysen-Jensen method. Whenever the method could not be applied, secondary production was estimated by the P/B ratio. The results showed that the epibenthic production was higher on the horizontal surface throughout the study. However, at the end of the study period, the mean production showed similar values. The horizontally oriented surfaces showed a mean production between 128 and 103 g m-2 yr-1, while at the vertical surfaces the mean production varied between 103 and 98 g m-2 yr-1. Furthermore, the mean annual production was extrapolated for all the Algarve artificial reef complex,and we concluded that after one year of deployment theses artificial reefs were able to generate around 5 MT of epibenthic fauna. R E S U M O Um dos aspectos menos estudados sobre o funcionamento dos recifes artificiais prende-se com a sua produção secundária. Nesse sentido, ao longo dos primeiros 12 meses após a implantação do recife artificial de Faro/Ancão (Algarve, Portugal), desenvolveu-se um estudo com o objectivo de avaliar o efeito da orientação do substrato na produção secundária de epibentos, usando o método de Boysen-Jensen. Nos casos em que não foi possível aplicar este método, a produção secundária foi estimada a partir da taxa P/B. Os resultados mostraram que a produção epibêntica foi mais elevada na superfície horizontal. No entanto, no final do período de estudo, a produção média apresentou valores semelhantes. As superfícies de orientação horizontal tiveram uma produção média entre 128 e 103 g m-2yr-1, enquanto as superfícies verticais apresentaram uma produção média entre 103 e 98 g m-2 yr-1. A partir destes valores extrapolou-se a produção média anual para o complexo recifal da costa algarvia, tendo-se concluído que após um ano de implantação este complexo recifal gera cerca de 5 toneladas de fauna epibêntica.
BOLETIN- …, 2003
The growth and survival of the polychaete Nereis diversicolor (OF Müller, 1776) fed on faeces of ... more The growth and survival of the polychaete Nereis diversicolor (OF Müller, 1776) fed on faeces of the carpet shell clam Ruditapes decussatus (L., 1758) were studied under controlled tempera-ture and salinity conditions. Juvenile worms were fed with clam R. decussatus ...
The feeding ecology of Nereis diversicolor (O. F. Müller, 1776) (Annelida: Polychaeta) was studie... more The feeding ecology of Nereis diversicolor (O. F. Müller, 1776) (Annelida: Polychaeta) was studied over 14 months at three estuarine-lagoon systems of the Southwest coast of Portugal (Odeceixe, Aljezur and Carrapateira). The analyses of digestive tract revealed that diet change according to site, period of the year and individual sizes. There are no differences in the digestive contents between sexes. In all sampling stations a total of thirty items were found, but only five shown an occurrence superior to 1%. These were: mucus (56.3%), sand (17.6%), vegetable detritus (10.7%), Nereididae (7.7%) and Corophium sp. (1.8%). N. diversicolor was detected in all sampling stations with a filter-feeding behaviour, although in Carrapateira there is evidence of slightly higher carnivore behaviour than in Odeceixe and Aljezur. Mucus (a food complex including organic matter, bacteria, fungi and phytoplankton) was the main gut content.
We report details of two PCR-based molecular sexing techniques for the Bonelli's Eagle (Hieraaetu... more We report details of two PCR-based molecular sexing techniques for the Bonelli's Eagle (Hieraaetus fasciatus) and evaluate the reliability of morphometric measurements to predict the sex of nestlings in the field. Blood samples taken from 63 nestlings in southwest Portugal (1994-99) were analyzed using the intron polymorphism method (M1), and 56 of these were also analyzed with the single-strand conformation polymorphism approach (M2). Contamination or poor preservation of samples precluded one sex determination with M1 and six others with M2. Sexing by both methods was concordant for 98.0% of samples. Linear discriminant analysis was used to determine whether any single variable or combination could provide reliable sex determinations, using 10 body measurements from 43 nestlings aged 35-50 d, sexed unambiguously by both molecular methods. Models were evaluated by cross-validation of the original data and from the classification of an external sample (N = 12). Females were significantly larger than males. The greatest separation between sexes occurred in body mass, but differences were also noted in tarsus diameter and the lengths of the hind claw, foot, culmen, and forewing; no differences were detected in the lengths of tarsus, fore claw, seventh primary, and central tail feather. A discriminant model including body mass, hind claw length, and age provided the maximum separation between sexes and it correctly sexed 96% of the nestlings. A model including tarsus diameter, hind claw, and age showed similar accuracy. Both models were satisfactory in determining the sex of nestling Bonelli's Eagles between the ages of 35-50 d in the field, but combination with molecular techniques may be preferable in studies requiring absolute precision for every individual handled.
Limnetica, 2017
Freshwater large branchiopods in Portugal: an update of their distribution This study is based la... more Freshwater large branchiopods in Portugal: an update of their distribution This study is based largely on 20 years of field and laboratory work, with surveys conducted by the authors and some other researchers. During this period several studies dealing with freshwater large branchiopods (FLB) were carried out, resulting in scientific publications and project reports. The distribution of FLB in Portugal was presented in 2 international scientific meetings, but apart from a first paper by Vianna-Fernandes in 1951 and an update done by ourselves in 1999 concerning the southwest Portugal, no other information has been published. Therefore, this work intends to bring up to date the known distribution of this faunal group in freshwater temporary systems. This is pertinent because of the recent revision of the taxon Triops cancriformis on the basis of genetic analyses. The Portuguese populations were assigned either to the Portuguese endemism T. vicentinus, or to T. baeticus, the more widely spread Iberian species, both belonging to the T. mauritanicus complex. Furthermore, a new species, Tanymastigites lusitanica was found and described in Portugal. More recently, a male free (or, at least, a strongly female-biased) metapopulation of T. cancriformis was discovered in a rice field in the central region of Portugal. Here we present an updated status of FLB species of Portuguese temporary lentic systems and their distribution, plotted on a UTM (10 × 10 km) grid. A total of 505 sites (temporary ponds or assemblages of closely located, not individual temporary pools) have been surveyed (455 by us). In 241 of these (47.7%) at least one species of FLB was found on at least one occasion. Of the 505 sites, only 87 are located north of the Tagus River and of these, at least one species was found in only 17 (19.5%). South of the Tagus River (Alentejo and Algarve), 53.6% of the sites were inhabited by at least one species. This list comprises 7 anostracans, 2 spinicaudatans and 4 notostracans, including 3 species endemic to the Iberian Peninsula and another 3 to Portugal.
Spanish Journal of Palaeontology
Revista Portuguesa de História
A região de Cabo Frio, área objeto deste estudo, está localizada na baixada litorânea do Estado d... more A região de Cabo Frio, área objeto deste estudo, está localizada na baixada litorânea do Estado do Rio de Janeiro, Brasil. As suas condições naturais, nomeadamente a existência do sistema lagunar de Araruama e a ocorrência do fenómeno da ressurgência no seu litoral, proporcionaram uma zona favorável à exploração de recursos marinhos, fomentando a fixação humana e o posterior desenvolvimento da pesca lagunar e costeira. Nesse sentido, a atividade apesar de ser praticada pelos povos indígenas estabelecidos na região, no século dezassete, com a efetivação da colonização portuguesa em Cabo Frio observou-se a sua intensificação e desenvolvimento. Tendo em conta as caraterísticas do meio no propiciar de recursos piscícolas, pretende-se analisar diacronicamente a evolução da prática piscatória na região, por meio da investigação de documentação histórica.
Ocean & Coastal Management
Limnetica, 2017
First record of the tadpole shrimp Triops cancriformis (Lamarck,1801) (Crustacea: Branchiopoda: N... more First record of the tadpole shrimp Triops cancriformis (Lamarck,1801) (Crustacea: Branchiopoda: Notostraca) in Portugal Notostracan crustaceans identified as Triops cancriformis according to the presently accepted morphological criteria were recorded for the first time in Portugal in 2007. All previous records of Triops in Portugal belong to mauritanicus lineage species i.e. T. vicentinus or T. baeticus. A specimen purportedly belonging to T. cancriformis (Carvalho, 1944) has been re-identified by Machado in 2014 as T. baeticus after morphological examination. During 2007, hundreds of individuals of T. cancriformis were observed throughout the rice paddies on the northern margin of Sorraia River (Vale do Sorraia, Coruche). In the last 9 years, monthly checks during the rainy season have failed to record high population abundances and only a few specimens have been observed in the flooded tracks left by trucks and other heavy machinery on the elevated margins of the paddies. The low number of individuals observed in the latter years possibly results from changes of ecological conditions. Thus far, males of T. cancriformis have not been recorded, which may indicate that the observed population is either androdioecious or made of hermaphrodite or parthenogenetic populations. This situation contrasts with the other confirmed populations of this species in the Iberian Peninsula that are gonochoric. Parthenogenetic/hermaphrodite/androdioecious lineages, present in Northern and Central Europe, are considered to have derived from gonochoric Iberian populations in the Pleistocene which makes this finding all the more interesting in evolutionary terms. Has this population resulted from a recent recolonization from non-Iberian populations? Or has it derived directly from the assumed Iberian Pleistocene refuge? The potentially high dispersal abilities of Triops diapausing cysts and the possibility of hermaphrodite/parthenogenetic reproduction favour the 1st hypothesis of recolonization. Possible sources of individuals are (i) cysts attached to migratory birds arriving possibly from Southern France or Northern Italy and that are regularly seen feeding at these rice fields or ii) cysts unwittingly transported with the rice seeds used in the Vale do Sorraia. Both are in accordance with the assumption that nongonochoric reproductive mode confers a colonization advantage over gonochoric populations, which lack evidence of fast long distance dispersal ability. Future multilocus phylogenetic analysis is expected to clarify the origin of T. cancriformis found in the Sorraia's rice fields.
Limnetica, 1999
Lagoa da Sancha as part of an ecological characterisation of the Alentejo littoral lagoonal syste... more Lagoa da Sancha as part of an ecological characterisation of the Alentejo littoral lagoonal systems. Lagoa da Sancha is North of the locality of Sines, and spreads over an area of approximately 4 ha. It has an elongate shape along a N-S axis, and receives water from a hydrographic basin of approximately 37 km 2. The lagoon can be considered a system in which communication with the sea, which could provide its renewal, is naturally established only very seldom according to local fishermen (an inlet has existed only once in the past 25 years). Overwash is the main source of sea water. This is revealed by salinity values, always below 5‰ (oligohaline), except for summer values, when values, may reach 12%o (mesohaline) due to evaporation. Of the 69 invertebrate taxa found, 89.8% can be considered as continental and 8.7% of lagoonal affinities (i.e. lagoonal-continental). Only few groups were present throughout the year, with a constant presence of continental species (e.g. Daphnia sp, Herpetocypris reptans, Cloeon sp., Plea leachi, Berosus sp., Chironomidae). Anomopoda and Chironomidae were the dominant groups. Individuals of brackish lagoonal species were rare during the sampling period. Results show this benthic community is very similar to that of temporary lentic systems, where the taxa succession is erratic.
Este trabalhoque não é um artigo científico e por isso não segue a sua estruturareúne um conjunto... more Este trabalhoque não é um artigo científico e por isso não segue a sua estruturareúne um conjunto de opiniões de vários investigadores que se dedicam ao estudo das zonas costeiras. A todos se pediu que reflectissemcom base na sua experiência pessoal e profissionalsobre a gestão actual deste espaço, partindo da frase do artista plástico Carlos Augusto Ribeiro, que serve de título a este texto. Aqui se discute sobre populações e saberes tradicionais, obras de engenharia costeira, gestão de conflitos, destruição de ecossistemas e insustentabilidade, necessidade de cooperação e conhecimento multidisciplinar, novos modelos de gestão do litoral e de cidadania.
Reviews in Aquaculture, 2018
Polychaetes are marine annelid worms that can contribute to aquaculture diversification. Its cult... more Polychaetes are marine annelid worms that can contribute to aquaculture diversification. Its culture has been viable, and commercially attempted, but intensive production has progressed only in few countries around the world. In the countries with no production, marine polychaetes are imported or harvested. A strong and sustained research investment provided to a better understanding of the nutritional requirements and reproduction of some species. Recent studies showed new technical improvements, which can lead to an important progress in productivity and give a new impetus to the polychaete production. Some marine worm species were identified as good candidates for integrated multitrophic aquaculture. The development of cost‐effective aquaculture techniques for marine annelid worms is essential to ensure a balance between commercial interests and the preservation of ecosystems. The influence of polychaete aquaculture on the environment and vice versa raise important concerns relat...
Hydrology Research, 2015
We examined the variation of stygofauna composition collected in wells, along a gradient in groun... more We examined the variation of stygofauna composition collected in wells, along a gradient in groundwater salinity/conductivity in a coastal aquifer from southern Portugal. The studied coastal aquifer is considered vulnerable to salinization due to seawater intrusion, caused by overexploitation of the aquifer. Knowing the response of the stygofauna species to present levels of groundwater salinity makes it possible to understand and measure the effects of saltwater intrusion on stygofauna, rendering them potential bioindicators of this environmental pressure. Biotic and abiotic sampling was conducted in six shallow wells located in the fresh–saltwater interface of the Arade estuary along the salinity gradient established in the groundwater from the estuary to inland locations (microSiemens/cm). Groundwater salinity was highly correlated with taxa distribution. The stygobites Eucyclops hadjebensis and Acanthocyclops sensitivus, the cosmopolitan Megacyclops viridis and Cypria ophtalmica...
The importance of Santo André Lagoon (SW Portugal) for the conservation of biodiversity has been ... more The importance of Santo André Lagoon (SW Portugal) for the conservation of biodiversity has been recognized over the last few years (Ramsar, SPA, Natura 2000). This is well demonstrated by its inclusion, since 2000, in the Portuguese Network of Protected Areas (Reserva Natural das Lagoas de Santo André e Sancha). In this circumstance, birds clearly stand out. Its avifauna includes a significant number of migratory species and/or a high conservation value, being the main reason for its choice as a site for regular bird ringing campaigns for nearly 30 years. Due to their relevance, waterbird species deserve special attention from management rules established in this protected area. During 2005 and 2006 the presence of aquatic birds was monitored monthly in different sectors of the lagoon. The results, besides showing high abundances of several species, confirm the importance of the area for the coot (Fulica atra), at a national level. Also important is the regular occurrence of the re...
Scientia Marina, 2006
The importance of the market for polychaetes dramatically increased after the discovery of their ... more The importance of the market for polychaetes dramatically increased after the discovery of their potential as food in aquaculture. In Portugal, the gathering of polychaetes solely from natural populations is not sufficient to meet market demand, both as bait for sea anglers and as a food item in aquaculture. The requests for worms to polychaete dealers by Portuguese and Spanish seafarms have increased during recent years. Due to the lack of intensive culture of these worms in Portugal and the proximity of southern Spanish farms, a large component of imported polychaetes that arrive in Portugal at Lisbon Airport go directly to Spain by road. In 2002 and 2003 a total of 12,728,379 and 16,866,839 polychaetes respectively were imported to Europe via Lisbon Airport from China and the USA. In 2003 the imports from China and the USA realised 716,180 and 291,845 US dollars respectively. Two species were reported to have been imported in these years, namely the Korean blue ragworm Perinereis aibuhitensis and the American bloodworm Glycera dibranchiata. Imports of non-indigenous species, which are traded and sold alive, may increase the risk of accidental introduction into the wild. This is of special concern as Perinereis aibuhitensis has been successfully reared in captivity within the range of environmental conditions existing in the Ria Formosa coastal lagoon. Other risks associated with introduced species are the transport of foreign pathogens and other associated non-native organisms, which may act as carriers of disease.
Journal of Applied Ecology, 2006
Summary Predator conservation management requires detailed understanding of the ecological circum... more Summary Predator conservation management requires detailed understanding of the ecological circumstances associated with predation, especially that on economically valuable prey. We examined the mechanisms behind Bonelli's eagle Hieraaetus fasciatus predation on prey of domestic origin, using dietary data from 22 pairs breeding in south‐west Portugal (1992–2001) together with information on landscape composition and prey availability. Numerically, 42·7% (37·7% in biomass) of eagle prey comprised domestic species, about 70% of which were rural pigeons Columba livia and the remainder were racing pigeons Columba livia and domestic fowl Gallus gallus. Rabbits Oryctolagus cuniculus, red‐legged partridges Alectoris rufa and jays Garrulus glandarius were the most frequent wild prey (43·1%; 50·8% in biomass). This dietary pattern was remarkably stable over a decade, but within each year the intake of pigeons almost halved over the course of the breeding season. Landscape composition sig...
Brazilian Journal of Oceanography, 2011
The secondary productivity of reef epifauna is one of the least investigated aspects in artificia... more The secondary productivity of reef epifauna is one of the least investigated aspects in artificial reef research. During the first 12 months after the deployment of the Faro/Ancão (Algarve, Portugal) artificial reef, we assessed the effect of substratum orientation on the secondary production of epibenthos, using the Boysen-Jensen method. Whenever the method could not be applied, secondary production was estimated by the P/B ratio. The results showed that the epibenthic production was higher on the horizontal surface throughout the study. However, at the end of the study period, the mean production showed similar values. The horizontally oriented surfaces showed a mean production between 128 and 103 g m-2 yr-1, while at the vertical surfaces the mean production varied between 103 and 98 g m-2 yr-1. Furthermore, the mean annual production was extrapolated for all the Algarve artificial reef complex,and we concluded that after one year of deployment theses artificial reefs were able to generate around 5 MT of epibenthic fauna. R E S U M O Um dos aspectos menos estudados sobre o funcionamento dos recifes artificiais prende-se com a sua produção secundária. Nesse sentido, ao longo dos primeiros 12 meses após a implantação do recife artificial de Faro/Ancão (Algarve, Portugal), desenvolveu-se um estudo com o objectivo de avaliar o efeito da orientação do substrato na produção secundária de epibentos, usando o método de Boysen-Jensen. Nos casos em que não foi possível aplicar este método, a produção secundária foi estimada a partir da taxa P/B. Os resultados mostraram que a produção epibêntica foi mais elevada na superfície horizontal. No entanto, no final do período de estudo, a produção média apresentou valores semelhantes. As superfícies de orientação horizontal tiveram uma produção média entre 128 e 103 g m-2yr-1, enquanto as superfícies verticais apresentaram uma produção média entre 103 e 98 g m-2 yr-1. A partir destes valores extrapolou-se a produção média anual para o complexo recifal da costa algarvia, tendo-se concluído que após um ano de implantação este complexo recifal gera cerca de 5 toneladas de fauna epibêntica.
BOLETIN- …, 2003
The growth and survival of the polychaete Nereis diversicolor (OF Müller, 1776) fed on faeces of ... more The growth and survival of the polychaete Nereis diversicolor (OF Müller, 1776) fed on faeces of the carpet shell clam Ruditapes decussatus (L., 1758) were studied under controlled tempera-ture and salinity conditions. Juvenile worms were fed with clam R. decussatus ...
The feeding ecology of Nereis diversicolor (O. F. Müller, 1776) (Annelida: Polychaeta) was studie... more The feeding ecology of Nereis diversicolor (O. F. Müller, 1776) (Annelida: Polychaeta) was studied over 14 months at three estuarine-lagoon systems of the Southwest coast of Portugal (Odeceixe, Aljezur and Carrapateira). The analyses of digestive tract revealed that diet change according to site, period of the year and individual sizes. There are no differences in the digestive contents between sexes. In all sampling stations a total of thirty items were found, but only five shown an occurrence superior to 1%. These were: mucus (56.3%), sand (17.6%), vegetable detritus (10.7%), Nereididae (7.7%) and Corophium sp. (1.8%). N. diversicolor was detected in all sampling stations with a filter-feeding behaviour, although in Carrapateira there is evidence of slightly higher carnivore behaviour than in Odeceixe and Aljezur. Mucus (a food complex including organic matter, bacteria, fungi and phytoplankton) was the main gut content.
We report details of two PCR-based molecular sexing techniques for the Bonelli's Eagle (Hieraaetu... more We report details of two PCR-based molecular sexing techniques for the Bonelli's Eagle (Hieraaetus fasciatus) and evaluate the reliability of morphometric measurements to predict the sex of nestlings in the field. Blood samples taken from 63 nestlings in southwest Portugal (1994-99) were analyzed using the intron polymorphism method (M1), and 56 of these were also analyzed with the single-strand conformation polymorphism approach (M2). Contamination or poor preservation of samples precluded one sex determination with M1 and six others with M2. Sexing by both methods was concordant for 98.0% of samples. Linear discriminant analysis was used to determine whether any single variable or combination could provide reliable sex determinations, using 10 body measurements from 43 nestlings aged 35-50 d, sexed unambiguously by both molecular methods. Models were evaluated by cross-validation of the original data and from the classification of an external sample (N = 12). Females were significantly larger than males. The greatest separation between sexes occurred in body mass, but differences were also noted in tarsus diameter and the lengths of the hind claw, foot, culmen, and forewing; no differences were detected in the lengths of tarsus, fore claw, seventh primary, and central tail feather. A discriminant model including body mass, hind claw length, and age provided the maximum separation between sexes and it correctly sexed 96% of the nestlings. A model including tarsus diameter, hind claw, and age showed similar accuracy. Both models were satisfactory in determining the sex of nestling Bonelli's Eagles between the ages of 35-50 d in the field, but combination with molecular techniques may be preferable in studies requiring absolute precision for every individual handled.
Limnetica, 2017
Freshwater large branchiopods in Portugal: an update of their distribution This study is based la... more Freshwater large branchiopods in Portugal: an update of their distribution This study is based largely on 20 years of field and laboratory work, with surveys conducted by the authors and some other researchers. During this period several studies dealing with freshwater large branchiopods (FLB) were carried out, resulting in scientific publications and project reports. The distribution of FLB in Portugal was presented in 2 international scientific meetings, but apart from a first paper by Vianna-Fernandes in 1951 and an update done by ourselves in 1999 concerning the southwest Portugal, no other information has been published. Therefore, this work intends to bring up to date the known distribution of this faunal group in freshwater temporary systems. This is pertinent because of the recent revision of the taxon Triops cancriformis on the basis of genetic analyses. The Portuguese populations were assigned either to the Portuguese endemism T. vicentinus, or to T. baeticus, the more widely spread Iberian species, both belonging to the T. mauritanicus complex. Furthermore, a new species, Tanymastigites lusitanica was found and described in Portugal. More recently, a male free (or, at least, a strongly female-biased) metapopulation of T. cancriformis was discovered in a rice field in the central region of Portugal. Here we present an updated status of FLB species of Portuguese temporary lentic systems and their distribution, plotted on a UTM (10 × 10 km) grid. A total of 505 sites (temporary ponds or assemblages of closely located, not individual temporary pools) have been surveyed (455 by us). In 241 of these (47.7%) at least one species of FLB was found on at least one occasion. Of the 505 sites, only 87 are located north of the Tagus River and of these, at least one species was found in only 17 (19.5%). South of the Tagus River (Alentejo and Algarve), 53.6% of the sites were inhabited by at least one species. This list comprises 7 anostracans, 2 spinicaudatans and 4 notostracans, including 3 species endemic to the Iberian Peninsula and another 3 to Portugal.
Spanish Journal of Palaeontology
Revista Portuguesa de História
A região de Cabo Frio, área objeto deste estudo, está localizada na baixada litorânea do Estado d... more A região de Cabo Frio, área objeto deste estudo, está localizada na baixada litorânea do Estado do Rio de Janeiro, Brasil. As suas condições naturais, nomeadamente a existência do sistema lagunar de Araruama e a ocorrência do fenómeno da ressurgência no seu litoral, proporcionaram uma zona favorável à exploração de recursos marinhos, fomentando a fixação humana e o posterior desenvolvimento da pesca lagunar e costeira. Nesse sentido, a atividade apesar de ser praticada pelos povos indígenas estabelecidos na região, no século dezassete, com a efetivação da colonização portuguesa em Cabo Frio observou-se a sua intensificação e desenvolvimento. Tendo em conta as caraterísticas do meio no propiciar de recursos piscícolas, pretende-se analisar diacronicamente a evolução da prática piscatória na região, por meio da investigação de documentação histórica.
Ocean & Coastal Management