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Some pouting caught off the Atlantic coast of Portugal are discarded as unmarketable due to a dark discolouration of the skin and muscle. This study investigates the cause of this condition, describes the new parasite species responsible, and highlights the importance of educating those in charge of premarket inspection of food fish in order to reduce likelihood that consumers will eat infected fish. Macroscopically, infected fish showed considerable heterogeneity in darkening of the skin and hypaxial and epaxial muscles. Microscopical observation revealed bipolar nematode eggs in varying stages of development arranged in a linear pattern along muscle fibers. Histopathology confirmed the presence of eggs of a nematode of the genus Huffmanela Moravec, 1987 as the cause of muscle darkening and established a relationship between infection intensity and consequent darkened appearance of the tissues. The eggs are oval or barrel-shaped, with a smooth surface and polar plugs at opposite ends. The thin outer vitelline membrane is smooth and lacks ornamentation. Under light microscopy, the main eggshell of older eggs exhibits the outermost delicate and smooth vitelline membrane, and a thicker layer, correspondent to chitinous and chondroitin proteoglycan layers. Scanning electron microscopy of eggs confirmed light microscopic studies, namely the presence of a smooth vitelline membrane surrounding the egg. Microscopic and ultrastructural characteristics of eggs, and a new host family in a new geographic area, all suggest that a new species, herein named Huffmanela lusitana sp. n. is involved. Image 1 • Huffmanela lusitana sp. n in Trisopterus luscus. • Dark muscle due to Huffmanela eggs. • H. lusitana sp. n as the cause of disgusting aspect of infected fish meat. • H. lusitana sp. n as a zoonotical potential infection to consumers. • H. lusitana sp. n. as a constraint factor of healthy wildlife stocks. [ABSTRACT FROM AUTHOR]

• Temperature thresholds restrict O. cf. ovata distribution range in Iberia. • Lisbon Bay is the current W Iberian northern distribution limit of O. cf. siamensis. • Positive SST anomalies favor the occurrence of Ostreopsis spp. in Lagos Bay. • Low sea state favor the occurrence of Ostreopsis spp. in Lagos Bay. The benthic genus Ostreopsis contains toxic-bloom forming species and is an important cause of concern in warm-temperate and tropical waters. On the coast of Portugal, NE Atlantic, the occurrence of Ostreopsis cf. siamensis and Ostreopsis cf. ovata has been reported since 2008 and 2011, respectively. This work aims to understand the favorable conditions for high concentrations of Ostreopsis cells in the plankton at two sites, Lagos and Lisbon Bays, located in the South and West coast of Portugal, respectively. This study is based on weekly Ostreopsis abundance data in the plankton, from 2011 to 2017, daily satellite and in situ sea surface temperature (SST), and meteorological and sea state parameters, namely wind stress and significant wave height. The molecular identification of local Ostreopsis spp. is also presented. The maximum cell densities occur between late-summer and autumn. The distribution range of Ostreopsis cf. ovata is restricted to the South coast, while Ostreopsis cf. siamensis has a wider distribution range, being also present on the West coast. In the study period, there was only one occurrence of Ostreopsis spp., in Lagos Bay, with concentrations within the alert phase of monitoring. In Lagos Bay, high Ostreopsis spp. concentrations were related with positive SST anomalies. These high concentrations were often recorded after a period of almost 2-weeks to more than 4-weeks of low sea state (<0.6 m), followed by short time events of onshore wind and moderate waves (0.6–1 m). The former conditions are interpreted as favoring bloom development on the substrate and the latter as causing the re-suspension of Ostreopsis cells in the water column. In Lisbon Bay, O. cf. siamensis occurred in the plankton in few occasions and no clear relation could be established with the studied environmental variables. It is here hypothesized that the recent records of O. cf. siamensis in Lisbon Bay may correspond to an early colonization stage of an invasion process. Knowledge gained on Ostreopsis dynamics along the Portuguese coast can be used for both the improvement of benthic harmful algal blooms (BHABs) monitoring in the region and as a basis to design forecasting models. [ABSTRACT FROM AUTHOR]

Abstract Innate immune status of the sea urchin Paracentrotus lividus population from two different rocky shore beaches in the northern Portuguese coast was evaluated for a period of one year. Although some ecological studies regarding the effect of toxics on the immune parameters of the sea urchin were made in Portuguese waters, there is a current lack of knowledge concerning their immune status all over the year. In perspective of a changing ecosystem in these waters due to global warming and colonization of new species, it is important to assess the status of the major species living in the area. In this way, immune parameters such as total protein content, nitric oxide concentration, haemolytic activity, protease activity, lysozyme concentration and bactericidal activity were evaluated in the perivisceral coelomic fluid, and were correlated with the gonadal index of the population and water parameters. Also, the spawning period can upset some immune status parameters, and others such as haemolytic activity and bactericidal activity against Vibrio anguillarum, showed a clear correlation with the gonad maturation status. The knowledge of the basal immune status of the species could serve as ecological indicator of some stress agent or contaminant into the field; also, coelomic fluid is suggested as good quality marker to assess the immune status of sea urchins. Highlights • Annual survey of the humoral innate system of Paracentrotus lividus. • Decrease of innate immune parameters due to spawning period. • Positive correlation of haemolytic activity and bactericidal activity with gonad maturation. • Small differences recorded between sampling sites; good status of the northern Portuguese coast population. • Perivisceral coelomic fluid suggested as a good quality marker for assessing health of sea urchins. [ABSTRACT FROM AUTHOR]

The consequences of reallocating fishing effort from trawling to creels in an area off the West coast of Portugal for the operation of the trawl fleet, as well as on the population dynamics and the global catch value for a high-valued species, the Norway lobster ( Nephrops norvegicus ) are evaluated. The results suggest that only small portions of the area of interest are used by the trawl fleet, opening the possibility for a trawl ban without major disruption of the trawling activity. Economic benefits are expected, since predictions two scenarios tested, heavy and moderate exploitation, indicate no loss of catch value with much lower operational costs. Social benefits to local communities can also be expected since a much lower investment is needed for creel fishing, making this fishery attractive to small local companies already operating in the region. The proposed ban is consistent with the ecosystem approach to fisheries management and the Common Fisheries Policy (CFP) where the transition towards more responsible fishing practices is encouraged. [ABSTRACT FROM AUTHOR]

Chlorophyll- a (Chl a ) is a key parameter for the assessment of water quality in coastal and shelf environments. The availability of satellite ocean colour offers the potential of monitoring these regions at unprecedented spatial and temporal scales, as long as a high level of accuracy can be achieved. To use satellite derived Chl a to monitor these environments, it is imperative that rigorous accuracy assessments are undertaken to select the most accurate ocean colour algorithm(s). To this end, the accuracy of a range of ocean colour Chl a algorithms for use with Medium Imaging Resolution Spectrometer (MERIS) Level 2 (L2) Remote Sensing Reflectance ( R rs ), using two different atmospheric correction (AC) processors (COASTCOLOUR and MERIS Ground Segment processor version 8.0 – MEGS8.0), were assessed in North West European waters. A total of 594 measurements of R rs (λ) and/or Chl a were made in the North Sea, Mediterranean Sea, along the Portuguese Coast, English Channel and Celtic Sea between June 2001 and March 2012, where Chl a varied from 0.2 to 35 mg m − 3 . The following algorithms were compared: MERIS Case 1 water Chl a algorithm OC4Me, the MERIS Case 2 algorithm Algal Pigment 2 (AP2), the MODIS-Aqua Case 1 Chl a algorithm OC3 adapted for MERIS (OC3Me), the MODIS-Aqua Garver-Siegel-Maritorena algorithm (GSM) adapted for MERIS and the Gohin et al. (2002) algorithm for MERIS (OC5Me). For both COASTCOLOUR and MEGS8.0 processors, OC5Me was the most accurate Chl a algorithm, which was within ~ 25% of in situ values in these coastal and shelf waters. The uncertainty in MEGS8.0 R rs (442) (~ 17%) was slightly higher compared to COASTCOLOUR (~ 12%) from 0.3 to 7 mg m − 3 Chl a , but for R rs (560) the uncertainty was lower for MEGS8.0 (~ 10%) compared to COASTCOLOUR (~ 13%), which meant that MEGS8.0 Chl a was more accurate than COASTCOLOUR for all of the Chl a algorithms tested. Compared to OC5Me, OC4Me tended to over-estimate Chl a , which was caused by non-algal SPM especially at values > 14 g m − 3 . GSM also over-estimated Chl a , which was caused by variations in absorption coefficient of coloured dissolved organic matter at 442 nm ( a CDOM (442)). AP2 consistently under-estimated Chl a , especially when non-algal SPM was > 4 g m − 3 . [ABSTRACT FROM AUTHOR]

Time-series models (Dynamic factorial analyses and; Min/max autocorrelation factor analysis) were used to explore the relative influences of environmental variables and fishing pressure of trawl, seine and artisanal fleets on catch rates on Trachurus trachurus in ICES IXa sub-divisions (IXaCN-North coast; IXa- CS-South coast; IXaS-Algarve, South coast, Algarve). Fishing effort influenced catch rates in all areas with a 2 year lag and fishing pressure for each area was related to specific fleet sectors effort. In IXaCN, winter upwelling (spawning peak) and both summer northerly wind and wind magnitude (outside of the spawning peak) were strongly correlated with catch rates. In IXaCS summer/autumn westerly winds were related with catch rates. Northerly winds in spring, upwelling and SST (winter and autumn) were related with catch rates in IXaS-Algarve. For species with a long spawning season such as horse mackerel, seasonal analyses at broad regional scales can detract from a better understanding of variability in short term sub-stock catch rates. Favorable environmental conditions, even during seasons with low spawning activity can positively affect catch rates. Ignoring the role of regional oceanographic features on the spatial distribution of the sub-stocks when analysing variability in catch rates can lead to poor inferences about the productivity of the populations. [ABSTRACT FROM AUTHOR]

The branched vs. isoprenoid tetraethers (BIT) index, which is based on the relative abundance of non-isoprenoidal, so-called branched glycerol dialkyl glycerol tetraethers (brGDGTs) versus a structurally related isoprenoid GDGT “crenarchaeol”, has been used to trace soil organic carbon (OC) from the continent to the ocean. However, it has been found in some locations that the BIT index can be primarily influenced by crenarchaeol concentrations and brGDGT production in fresh water rather than by soil-derived brGDGT concentrations. This may hamper the application of this proxy as an indicator for the input of soil OC. In order to constrain the applicability of the BIT index along the southern Portuguese continental margin, we examined the source of brGDGTs and crenarchaeol, by investigating their concentration and distribution as well as variations in the BIT index in marine surface sediments from five transects (Douro, Mondego, Estremadura, Tagus, and Sado) and in marine suspended particulate matter (SPM) from the Douro and Tagus transects. Higher BIT values and brGDGT concentrations (normalized to OC content) were found close to the river mouths and coast than in deep offshore sites. This clearly indicated the continental input of brGDGTs and revealed that, at least in this setting, the BIT index was primarily influenced by the delivery of brGDGTs from the rivers. BrGDGT concentrations and distributions in sediments and SPM close to the rivers were similar to those of SPM in the Tagus River. This indicates that degradation processes in the estuaries had no significant effect on the riverine brGDGTs. Therefore, brGDGTs should be a good indicator for the recalcitrant OC fraction transported from the continent to the ocean. Our results also indicated that there are multiple sources of brGDGTs in the marine environment, i.e. the water column and the sediment, which complicates the use of the brGDGT distribution as an indicator for terrestrial vs. marine produced brGDGTs. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the importance and the implication of the climate changes on coastal areas may be one of the major issues for this and next centuries. Climate changes may, indeed, impact the nearshore marine ecosystem, as coastal areas are very sensitive to the strength and the variability of the meteorological forcings. The main purpose of this work is to study temperature and phytoplankton distributions along the Portuguese near coastal zone during upwelling events in the present climate conditions and in a future climate scenario. The SRES-A2 IPCC scenario has been considered. We have used a three-dimensional model for coastal and shelf seas, including the following sub-models: hydrodynamical/physical, biological, sediment and contaminant. The forcings are provided by the interactions at the air–sea, considering the wind intensity and direction with the help of the WRF model (Weather Research and Forecast Model) and the coupled atmosphere–ocean model ECHAM5/MPI-OM. Results show that, for the future climate scenario, there is a reinforcement of the southward wind. The responses of the coastal ecosystem corresponds to the reinforcement of both, the southward (up to 10cm/s) and the westward (up to 6cm/s) induced upwelling currents. This, in turn generates an enlargement of the near coast upwelled cold layer, extending up to 60km, as well as the rise of the warm layer temperature (up to 2.0°C) and the spreading of the phytoplankton offshore. Significant changes in both the Chl-a vertical and the horizontal distribution patterns have been observed, as the nutrient supply to the upper layers depends on the strength of the upwelling, the bottom topography and orography of the coastal. These results confirm that changes in the strength and eventually the frequency of the upwelling favourable wind impact the phytoplankton distribution, which can have significant effect in the distribution and population of the upper level of the trophic chain of the coastal ecosystem. [Copyright &y& Elsevier]

Abstract: Benthic macroinvertebrates communities are the most consistently emphasized biotic component of aquatic ecosystems and are one of the biological indicators required for assessment by the European Water Framework Directive. In this context, several indices based on these communities have been developed in order to assess ecological quality of estuarine systems. In the present work we used AMBI, M-AMBI, BENTIX and BAT to distinguish ecological status of five small estuarine systems of the Portuguese south and southwest coasts. Although indices outputs did not differ between systems and sampling seasons, results indicated that the metrics in which these indices are based could differentiate community structures as a result of two main gradients that force these communities: the natural variability, and the anthropogenic impact. [Copyright &y& Elsevier]

Abstract: Organotin compounds (OTs) are ubiquitous in the marine environment and high concentrations (μgg−1 range) in sediments from different coastal areas around the world have been reported. However, few reports have described the OTs contamination status in the offshore and deep sea environment. This work investigated organotin levels in Nazaré canyon for the first time. Levels of monobutyltin (MBT), dibutyltin (DBT), tributyltin (TBT), diphenyltin (DPT), triphenyltin (TPT), dioctyltin (DOT) and trioctyltin (TOT) were quantified in sediment samples from the upper flanks of the canyon and from the adjacent coastal area. TBT levels detected in the canyon flanks are about two to three orders of magnitude lower than those found in the coastal area. Nevertheless, when quantifiable, TBT levels in the canyon samples were higher than the Environmental Assessment Criteria set for TBT in sediments by the OSPAR Commission indicating that at those locations negative ecological impacts are likely to occur. [Copyright &y& Elsevier]

Abstract: The distribution and composition of phytoplankton assemblages were studied in the Nazaré submarine canyon, during an upwelling event, using high-performance liquid chromatography (HPLC) pigment analysis, complemented by microscopic qualitative observations. High chlorophyll a (Chl a) concentrations were recorded in the canyon head, near the coast, where values greater than 4μgL−1 were observed. In contrast, Chl a was relatively low in offshore regions, with values below 0.5μgL−1. The most abundant accessory pigments were fucoxanthin, peridinin, diadinoxanthin and 19′-hexanoyloxyfucoxanthin. Pigment data information was analyzed using the CHEMTAX software to estimate the contribution of different taxonomic groups to total Chl a. North of the canyon head, an area with high concentration of peridinin-containing dinoflagellates was identified (with presence of chain-forming toxic dinoflagellates). The presence of these organisms was associated with mixed water columns and phosphate values lower than the ones south of the canyon head, where a dominance of diatoms was recorded. The rest of the study region showed a dominance of prymnesiophytes and a significant contribution of cyanobacteria at oceanic stations. This study demonstrates the usefulness of using pigment analysis to study spatial distribution of phytoplankton groups in relation to a complex physical environment. [Copyright &y& Elsevier]

Abstract: The importance of establishing the ecological quality of estuarine systems has been widely acknowledged and led to the development of several fish community-based multimetric indices. Nevertheless, a question rose about the accuracy of these tools when natural disturbance is acting upon the organization of the systems’ communities. Four multimetric indices were used to examine their ability to differentiate the ecological status of five small estuarine systems (southern Portugal), and also to test if they reflected the level of anthropogenic pressures. Fish assemblages from Mira, Odeceixe and Aljezur (in the Southwest coast), Gilão and Bensafrim (in the South coast) estuaries were sampled seasonally for one year, and anthropogenic sources of pressure were identified and quantified. We found that although the applied indices provided information on ecological condition differentiation among systems, they are unable to explain different classes of ecological status in systems with equivalent pressure levels. [Copyright &y& Elsevier]

Abstract: The aim of the study was to analyse the size, growth and size at maturity of Nephrops norvegicus in two areas off the Portuguese coast. Samples were collected between September 2006 and January 2007. A total of 2081 individuals ranging between 25 and 88mm carapace length were collected, measured and sexed. The estimated growth parameters were L ∞ =88.33mm CL, k =0.38years−1 for males and L ∞ =64.45mm CL, k =0.38years−1 for females in the northern area, and L ∞ =94.86mm CL, k =0.41years−1 for males and L ∞ =69.20mm CL, k =0.44years−1 for females in the central area. Size at maturity was 50.7mm CL in the northern area and 46.9mm CL in the central area. [Copyright &y& Elsevier]

Abstract: Imposex levels and organotin tissue concentrations were assessed in Nassarius reticulatus females collected between June and August 2008 at 23 sites along the Portuguese coast. Females with imposex were present at all sampling sites with highest levels inside main harbors. Imposex parameters across sampling stations varied between 6.3% and 100% for %I, 0.2–4.4 for VDSI, 0.1–7.8mm for FPL, 0.3–88.9% for RPLI and 0.0–1.1 for AOS. TBT levels varied between 3.5 and 380ngSng−1 dw, representing an average proportion of 50.4% of total butyltins (∑BTs=MBT+DBT+TBT). Sterile females were detected at two locations. Highly significant correlations between imposex and TBT levels were found. The efficacy of the EU legislation banning the use of TBT-based antifouling paints since 2003 (EC Regulation 782/2003) was evaluated by comparing the levels of imposex observed in 2008 with those reported for 2003. OTs tissue concentrations were also determined in preserved samples collected in 2003. There was a decrease in imposex and TBT tissue contamination between 2003 and 2008 indicating that a decline in TBT pollution has occurred in the Portuguese coast since the implementation of the legislation. Considering that the EC Regulation 782/2003 is an anticipation of the IMO AFS Convention, a global scale decrease in TBT pollution can be expected in the near future. Despite the rapid amelioration in the Portuguese coast, TBT pollution is still a problem as the Ecological Quality Objective (EcoQO) proposed by OSPAR Commission was not achieved in 91% of the surveyed sites. [Copyright &y& Elsevier]

Abstract: Despite the huge amount of literature available on butyltins (BuTs), few studies addressed the environmental levels of phenyltins (PhTs), octyltins (OcTs) and total tin (SnT) in environmental samples. In 2006 a mussel watch survey was developed for the Portuguese coast (total of 29 sampling sites) in order to describe the concentrations of BuTs , PhTs, OcTs and SnT in the whole tissues of Mytilus galloprovincialis (Lamarck, 1819). BuTs were detected in all analyzed samples accounting, in average, for 98.6% of total organotins (∑OTs=BuTs+PhTs+OcTs), and presented highest values in the vicinity of harbors. Tributyltin (TBT) was the dominant butyltin, representing, in average, 62% of ∑BuTs (∑BuTs=TBT+DBT+MBT) suggesting that fresh inputs of TBT are still occurring in the Portuguese coast, particularly near harbors. The contribution of organotin compounds derived from antifouling paints to the total tin levels in M. galloprovincialis is discussed. [Copyright &y& Elsevier]

Abstract: In this paper, the potential improvement of size-selectivity by increasing codend mesh size and changing twine type is addressed for the main commercial species exploited by crustacean trawlers in waters off the Portuguese south coast. Three cruises were conducted between autumn 1998 and summer 1999 onboard the F/V “Porto Bravo”, resulting in a total of 93 valid hauls using 3 different sizes of diamond mesh in the codend (stretched nominal sizes of 55, 70 and 80mm) and 2 types of twine, polyamide and polyethylene. A non-linear mixed-effects model was employed to include the effect of covariates and between-haul variation in the estimation of codend selectivity parameters for the main target species in this fishery, Norway lobster, Nephrops norvegicus (L.), rose shrimp, Parapenaeus longirostris (Lucas 1846), and ‘blue and red’ shrimp, Aristeus antennatus (Risso, 1816). The chosen selectivity model found a significant (p <0.001) linear effect of mesh size for all three target species, and a significant effect of cruise for Norway lobster (p <0.05) and rose shrimp (p <0.001). The cruise effect was due to a difference between the autumn 1998 cruise and the two latter cruises. This effect coincides with a change from polyamide twine in the autumn cruise to the use of polyethylene twine in the latter cruises. Other covariates, such as depth, codend-catch weight and species catch weight did not show any systematic effect on selectivity and thus were not included in the final models. The retention of a high number of undersized (or immature) individuals, while using the legal minimum mesh sizes, suggests the need for a change in the status quo fishing pattern. [Copyright &y& Elsevier]

Abstract: The population differentiation of seven flatfish species, Citharus linguatula, Lepidorhombus boscii, Platichthys flesus, Microchirus azevia, Solea lascaris, Solea senegalensis and Solea solea, widely distributed along the eastern north Atlantic and occurring in sympatry along the Portuguese coast was studied using morphological and parasitological data. Fish were obtained from commercial fishing vessels operating in three locations along the Portuguese coast (north, centre and south) between January 2003 and June 2005. Eleven morphometric and seven meristic characters were considered in morphological analyses. Size effect was removed from morphometric measurements by principal component analysis and a multivariate discriminant analysis was performed to investigate the differences between populations using both morphometric and meristic data, separately. Individuals were examined for macroparasites infections according to standard procedures, and a multivariate discriminant analysis was also applied to investigate population differences. Analyses of both types of data (morphological and parasitological) revealed a similar pattern of a generally low differentiation evidenced by the high overlap of individuals in the ordination diagrams. However, some differentiation was found between samples from the west (north and centre) and the south Portuguese coast evidencing the existence of an ecological differentiation along the Portuguese coast. Broad scale population studies should, therefore, take into account the information provided by such data, especially with regard to fisheries’ management policies and stock definition. [Copyright &y& Elsevier]

Abstract: The concentrations of V, Mn, Fe, Ni, Cu, Zn, As, Se, Mo, and Pb were measured in digestive gland (DG), branchial hearts (BH), gill (G), and muscle (M) of Octopus vulgaris Cuvier, 1797 caught in three fishing areas of the Portuguese coast, Viana do Castelo, Cascais, and Santa Luzia, for 2 years. The elemental concentrations measured for the different tissues were in accordance with values reported in the literature. The digestive gland presented high concentration levels of Fe, Cu, and Zn, while the branchial hearts showed elevated levels of V, Ni, Mo, as well as Fe and Cu. Significant variations in As, V, Cu, Mo, and Pb tissue concentrations were observed for animals originated from different sampling sites. Pb and As determined in the digestive gland and branchial hearts of animals from Cascais and Santa Luzia, can reflect local environmental characteristics. The variability observed in the elemental concentrations may be useful to further assess the specie susceptibility to environmental conditions. [Copyright &y& Elsevier]

This study characterises Perkinsus atlanticus disease prevalence and intensity within the economically important beds of the clam Ruditapes decussatus along the Iberian Atlantic coast. Samples were collected from five different sites along the Portuguese coast (Ria Formosa, Ria do Alvor, V.N. Milfontes, Aveiro, Lagoa de Obidos) and in Galicia (Ria de Arosa) between winter 2000/2001 and 2002/2003. The infection level was evaluated by the Ray Fluid Thioglycollate medium (RFTM) method using the body burden assay. In addition, the measure of the condition index (CI) (percentage between the edible part and the total weight of the clams) was conducted to investigate a possible correlation between this parameter and the intensity of the infection. However, no clear relationship between infection intensity and condition index (CI) could be determined although a significant decline in CI was found for heavily infected clams. Results of a 2-year survey demonstrate the presence of Perkinsus sp. in all sampling sites albeit with different intensities. Sites where human interference was minimal showed the lowest levels of infection. There were no significant differences in Perkinsus sp. infection intensity between samples collected in winter and summer, in contrast with several studies describing higher intensities at the end of the summer. Nevertheless, major differences were observed from year to year and site to site, indicating that factors other than those responsible for seasonal climatic variations might affect the prevalence and the intensity of Perkinsus sp. infection. [Copyright &y& Elsevier]

Plastic pollution and the subsequent entanglement of marine animals is a global and increasing problem. In this study we present an analysis of the seabirds recorded as entangled by a rehabilitation centre and an associated marine animal stranding network, along the central coast of Portugal, between 2008 and 2018. Results show a high annual rate of entangled seabirds (average 6.9%) compared to other studies and fisheries related materials are a relevant cause of seabird entanglement (82%) compared to other debris. When comparing age classes, juveniles were more vulnerable to entanglement than other age classes in the species studied. Regarding the rehabilitation of entangled seabirds, the release rate was higher in non-fishing material entanglement cases. In conclusion, this study highlights the impact of fisheries related material on marine fauna and the need for reinforcement of the existing legislation for protecting seabirds and the implementation of mitigation measures associated with fishing activities. • Fisheries related materials are a relevant cause of seabird entanglement. • Juveniles were more vulnerable than other age classes in the studied species. • Less than 50% of the alive entangled birds could be rehabilitated. • Entanglement cases with non-fishing material had higher rehabilitation success. [ABSTRACT FROM AUTHOR]

Bottom-trawl fishing for crustaceans off the Portuguese south and southwest coasts is a very important segment of the Portuguese fishing fleet, where annual rates of discarding have ranged from approximately 38% to as much as 70% of the total catch. Past experiments to address this problem encompassed the testing of different codend mesh sizes and configurations, square mesh windows and rigid grids to enhance species and size-selectivity. While the use of a Nordmøre grid has proved quite efficient in separating out blue whiting (Micromesistius poutassou), it also led to some losses of the two main crustacean target species, Norway lobster (Nephrops norvegicus) and rose shrimp (Parapenaeus longirostris). The present study addresses that limitation by using a modified grid with 20 mm bar spacing and two open sections, designed with the purpose of separating fish and crustacean species into upper and lower codends. Good separation was achieved, with about 80% of the blue whiting (in number) directed towards the upper trawl section and caught in the upper codend, while a similar percentage of Norway lobster was caught in the lower codend. The grid bars had 50% retention for Norway lobster at 34.1 mm carapace length. The results herein will enable this gear configuration to be fine-tuned with regard to codend mesh sizes and bar spacing, so as to optimize both retention of Norway lobster and exclusion of blue whiting. For example, compared to using the minimum 70 mm diamond mesh size, using an 80 mm diamond mesh upper codend would reduce Norway lobster catch weight by just 1.6% but reduce the number of blue whiting caught by 42%. [ABSTRACT FROM AUTHOR]

In order to investigate the distribution of polychlorinated biphenyls (PCB) congeners and DDT compounds in the Portuguese coast, we analysed material collected in 20 μm plankton nets and seston collected in April 1999, February and July 2000 at 1 mile from the mouth of the estuarine systems and on two stations away from the freshwater inputs. Contamination in seston and plankton material revealed N-S variations that changed with the season. Seston showed marked increases of tPCB at SW/S stations in July (102–410 ng g–1) and occasional peaks of tDDT (17–47 ng g–1). Higher contamination was found in material with low Al content, which appears to be related to the presence of biogenic particles that were not retained in 20 μm plankton nets. Plankton material contained higher tPCB and tDDT concentrations at northern stations although the intensity of the geographic signal varied with the season. Contaminant levels in this material appear to reflect river inputs to the NW coast. pp’DDT and pp’DDD constitute the larger fractions of DDT compounds, indicating the occurrence of low degradation rates of DDT in the Portuguese coastal waters. [Copyright &y& Elsevier]