Doubleday Z.A.,University of Adelaide |
Prowse T.A.A.,University of Adelaide |
Arkhipkin A.,University of Aberdeen |
Pierce G.J.,University of Aveiro |
And 6 more authors.
Current Biology | Year: 2016
Human activities have substantially changed the world's oceans in recent decades, altering marine food webs, habitats and biogeochemical processes . Cephalopods (squid, cuttlefish and octopuses) have a unique set of biological traits, including rapid growth, short lifespans and strong life-history plasticity, allowing them to adapt quickly to changing environmental conditions [2-4]. There has been growing speculation that cephalopod populations are proliferating in response to a changing environment, a perception fuelled by increasing trends in cephalopod fisheries catch [4,5]. To investigate long-term trends in cephalopod abundance, we assembled global time-series of cephalopod catch rates (catch per unit of fishing or sampling effort). We show that cephalopod populations have increased over the last six decades, a result that was remarkably consistent across a highly diverse set of cephalopod taxa. Positive trends were also evident for both fisheries-dependent and fisheries-independent time-series, suggesting that trends are not solely due to factors associated with developing fisheries. Our results suggest that large-scale, directional processes, common to a range of coastal and oceanic environments, are responsible. This study presents the first evidence that cephalopod populations have increased globally, indicating that these ecologically and commercially important invertebrates may have benefited from a changing ocean environment. © 2016 Elsevier Ltd.
Changes in the abundance and spatial distribution of the Atlantic chub mackerel (Scomber colias) in the pelagic ecosystem and fsheries off Portugal [Cambios en la abundancia y distribución espacial del estornino del Atlántico (Scomber colias) en el ecosistema pelágico y pesquerias de portugal]
Martins M.M.,Instituto Portugues do Mar e Atmosfera |
Skagen D.,Fjellveien 96 |
Marques V.,Instituto Portugues do Mar e Atmosfera |
Zwolinski J.,University of California at Santa Cruz |
Silva A.,Instituto Portugues do Mar e Atmosfera
Scientia Marina | Year: 2013
This study describes changes in abundance and spatial distribution of Atlantic chub mackerel in the Portuguese waters and the Spanish waters of the Gulf of Cadiz using data from acoustic surveys from 1995 to 2010 and data from the fishery since 1958. The distribution and dynamics of chub mackerel and sardine (Sardina pilchardus) are compared and species interactions are discussed. From 2007 to 2009, chub mackerel biomass, as measured acoustically, ranged between 69000 and 238000 t concentrated off the western coast (~50%) and in the Gulf of Cadiz (~30%). Portuguese landings have varied with periods of high landings around 1970 and in recent years. Since 1986 landings have been between 4000 and 23000 t. Both survey catches and commercial landings are taken mainly off the southwestern coast and one- to two-year-old individuals (20-24 cm) predominate in both. Scarcity of larger individuals may be a consequence of their deeper distribution and avoidance of fishing gear, migration of older individuals or a combination of both. In years with high abundance, the fishery expands to the northwestern areas of the Iberian Peninsula. The expansion appears to be caused by improved recruitment although other factors might have contributed (such as targeting to compensate for low sardine catches and the appearance of new markets). The complementary spatial distribution of chub mackerel and sardine and the inverse correlations between their frequency of occurrence, landings and recruitment indices suggest some interaction between the dynamics of the two species, possibly associated with climatic variation.
Lopez-Sanmartin M.,IFAPA Centro Agua del Pino |
Lopez-Fernandez J.R.,IFAPA Centro Agua del Pino |
Cunha M.E.,Instituto Portugues do Mar e Atmosfera |
De La Herran R.,University of Granada |
Navas J.I.,IFAPA Centro Agua del Pino
Diseases of Aquatic Organisms | Year: 2016
This is the first report of ostreid herpesvirus 1 microvariant (OsHV-1 μVar) infecting natural oyster beds located in Huelva (SW Spain). The virus was detected in 3 oyster species present in the intertidal zone: Crassostrea gigas (Thunberg, 1793), C. angulata (Lamarck, 1819) and, for the first time, in Ostrea stentina Payraudeau, 1826. Oysters were identified by a specific polymerase chain reaction (PCR) and posterior restriction fragment length polymorphism (RFLP) analysis based on cytochrome oxidase I (COI) mitochondrial DNA. Results confirmed that C. angulata still remains the dominant oyster population in SW Spain despite the introduction of C. gigas for cultivation in the late 1970s, and its subsequent naturalization. C. angulata shows a higher haplotype diversity than C. gigas. OsHV-1 virus was detected by PCR with C2/C6 pair primers. Posterior RFLP analyses with the restriction enzyme MfeI were done in order to reveal the OsHV-1 μVar. Detections were confirmed by DNA sequencing, and infections were evidenced by in situ hybridization in C. gigas, C. angulata and O. stentina samples. The prevalence was similar among the 3 oyster species but varied between sampling locations, being higher in areas with greater harvesting activities. OsHV-1 μVar accounted for 93% of all OsHV-1 detected. © Inter-Research 2016.
Jardim E.,European Commission - Joint Research Center Ispra |
Jardim E.,Instituto Portugues Do Mar e Atmosfera |
Millar C.P.,European Commission - Joint Research Center Ispra |
Millar C.P.,Marine Scotland - Marine Laboratory |
And 6 more authors.
ICES Journal of Marine Science | Year: 2014
This manuscript discusses the benefits of having a stock assessment model that is intuitively close to a linear model. It creates a case for the need of such models taking into account the increase in data availability and the expansion of stock assessment requests. We explore ideas around the assessment of large numbers of stocks and the need to make stock assessment easier to run and more intuitive, so that more scientists from diverse backgrounds can be involved. We show, as an example, the model developed under the European Commission Joint Research Center's 'Assessment for All' Initiative (a4a) and how it fits the a4a strategy of making stock assessment simpler and accessible to a wider group of scientists. © 2014 © International Council for the Exploration of the Sea 2014. All rights reserved.
Hansen B.W.,Roskilde University |
Buttino I.,European Commission - Joint Research Center Ispra |
Cunha M.E.,Instituto Portugues do Mar e Atmosfera |
Drillet G.,The Clean Tech Center
Aquaculture | Year: 2016
Calanoid copepods from the genus Acartia are well studied because they are promising live feeds in marine larviculture. Several Acartia spp. are adapted to the occurrence of sudden unfavorable environmental conditions and can arrest their embryogenesis by entering quiescence. This trait can be used practically for establishing an egg bank, where embryos can be kept alive and hatched at a later time. The stored embryos can be shipped to end-users and the hatched nauplii used directly as live feed as well as they can be used to establish new copepod cultures. Acartia tonsa (Dana) is a cosmopolite and therefore an obvious candidate for being mass produced centrally at specific offsite installations, transferred and used worldwide. Moreover embryos from other species from this genus are shown in the present paper to have similar capacities in terms of survival in cold storage. To avoid the transfer of exogenous species in new environments, it is recommended to cultivate regional or even local species of copepods. In the present contribution we compare the cold storage capacity of embryos produced by seven strains of Acartia spp. isolated from different zoogeographical regions ranging from Northern Europe to the subtropical USA and tropical Asia. Our results showed that cold storage capacity of embryos is very dependent on egg size. The longest storage capacity, with egg hatching success >. 50% is demonstrated for embryos originating from temperate European waters and in particular from Adriatic Mediterranean and Baltic Sea waters (240 and 150 days, respectively) while the shortest storage capacities were found from species from sub-tropical Mexican Gulf, USA (10 days). Higher survival has a tendency to correlate with larger egg biovolume. However, we cannot exclude a possible and unknown unidirectional selection for embryo storage tolerance caused by the management practice in long term continuous cultures. We conclude that the studied embryos from the genus Acartia can all be stored for different time periods and hence are relevant for being used as regional/local egg banks and further studies for developing future live feed items. Statement of relevance: We consider calanoid copepod live feed products as a valuable supplement or alternative source for hatcheries. This is due to the fact that by introducing copepod nauplii as first feed items more fish species with small mouth gapes will be cultivated. Copepod organisms cannot be shipped due to the fact that they are fragile organisms. However, their embryos in a cold storage situation enter arrested development that lasts viable for months. We investigate seven strains of Acartia spp. embryos for their capabilities to be cold stored and conclude that all strains have that capability. This is considered promising for future mass production of calanoids for the benefit of the industry. © 2016 Elsevier B.V.
Santos-Echeandia J.,Instituto Portugues do Mar e Atmosfera |
Santos-Echeandia J.,CSIC - Institute of Marine Research |
Caetano M.,Instituto Portugues do Mar e Atmosfera |
Brito P.,Instituto Portugues do Mar e Atmosfera |
And 2 more authors.
Marine Environmental Research | Year: 2012
The Water Framework Directives aims a reduction in concentration of hazardous substances in the marine environment. Consequently, there is a need to distinguish between anthropogenically influenced metal concentrations from natural background levels. To better achieve this goal in the Portuguese coast, dissolved and particulate trace metal (TM) concentrations along the Portuguese coast were determined in 46 sites distance 1-3 km from the shoreline. Dissolved values ranged within the following intervals: 0.01-0.89 nM for Cd, 0.01-3.37 nM for Co, 0.90-45.4 nM for Cu, 3.30-140 pM for Hg, 1.88-15.1 nM for Ni, 0.01-0.15 nM for Pb and 1.40-62.0 nM for Zn. Whereas Cd, Co, Cu, Ni and Zn were enhanced in the southern coast, while Pb values were higher in the central part of the western coast. Mercury concentrations showed punctual increases all along the coast. Values of trace metals in suspended particulate matter varied in a broad range: 36-2902 μmol g -1 for Al, 0.10-15.1 nmol g -1 for Cd, 1.50-165 nmol g -1 for Co, 50.0-990 nmol g -1 for Cu, 2.80-76.4 nmol g -1 for Hg, 22-1471 nmol g -1 for Ni, 10.0-347 nmol g -1 for Pb and 416-10,981 nmol g -1 for Zn. Higher values for Al, Ni and Co were found in the central part of the western coast. However, Cd, Cu, Pb and Zn increased their levels from the north coast towards the central and south areas. The variability of both dissolved and particulate metals appears to be mainly associated with oceanographic conditions and continental inputs at North and central areas of the coast, and in the south coast to geological features rather than to anthropogenic pressures. On the basis of these results, regional baseline concentrations are proposed for the three typologies in Portuguese coastal waters defined under the Water Framework Directive. © 2012 Elsevier Ltd.
Pereira A.M.,Instituto Portugues do Mar e da Atmosfera |
Range P.,University of Algarve |
Range P.,Qatar University |
Campoy A.,University of Algarve |
And 5 more authors.
Regional Environmental Change | Year: 2016
Noticeable changes in global temperatures, climate and ocean carbon chemistry are the result of carbon dioxide increase in the atmosphere. This increase has been mitigated by the oceans capacity to absorb one-fourth of the carbon dioxide in the atmosphere, although this CO2 intake affects oceans carbonate chemistry [i.e., ocean acidification—(OA)]. The detrimental effect of OA in the development and shell formation has been studied in several species of bivalves, although no information is available on the wedge shell Donaxtrunculus, a gastronomically appreciated species and an important economical resource in several southern European countries. We evaluated the effect of pCO2 increase on hatching and early life stages of D.trunculus, considering two ocean acidification scenarios (ΔpH −0.3 and ΔpH −0.6). Our results showed that elevated pCO2 caused a delay in hatching into D-larvae and reduced larvae survival. In the extreme scenario (ΔpH −0.6), some trochophore larvae persisted to day 9 of the experiment and more abnormal larvae were produced than in the ΔpH −0.3 and control treatments. At day 5, normal veligers under extreme acidification were smaller than in other treatments, but by day 9, these differences were attenuated and the average size of normal D-larvae varied inversely to the pH gradient. Possible underlying mechanisms for these complex response patterns are discussed, including the existence of phenotypic plasticity or genetic pre-adaptive capacity in this D.trunculus population to cope with future environmental changes. © 2015, Springer-Verlag Berlin Heidelberg.
Matias D.,Instituto Portugues do Mar e Atmosfera |
Joaquim S.,Instituto Portugues do Mar e Atmosfera |
Matias A.M.,Instituto Portugues do Mar e Atmosfera |
Moura P.,Instituto Portugues do Mar e Atmosfera |
And 4 more authors.
Aquaculture | Year: 2013
The reproductive cycle, as well as its nutrient storage and utilization, of two populations of Ruditapes decussatus from the main production areas of this species: Ria de Aveiro and Ria Formosa Lagoon (Portugal) were studied here over a 24. month period (May 2010-April 2012). The reproductive cycle of both populations of R. decussatus followed an annual cyclicality that comprised a ripe stage in spring followed by a spawning period that began in late spring and extended throughout summer until early autumn. This extended and continuous spawning period may be an advantageous strategy for this species by ensuring a continuous supply of gametes. Moreover, R. decussatus can adopt different reproductive strategies depending on the geographical origin. The results of both cycle of nutrients stored and nutrients utilization showed that clams of both populations present a high reproductive effort that almost depletes its energy reserves. Nevertheless, while Ria de Aveiro population retrieves them immediately after spawning, the same is not verified in clams from Ria Formosa Lagoon with their consequent debilitation. Also, based on the glycogen pattern it was possible to infer that the Ria Aveiro population is an opportunistic one, while the Ria Formosa Lagoon population exhibited an intermediate strategy. However, both populations could be considered as viable broodstock for intensive hatchery production of juveniles and the observed extended spawning periods presents interesting implications for the implementation of profitable aquaculture. Moreover, this species presented a great capacity for gonadal regeneration, which coupled with its high gonadal development rate would provide larvae during most of the year without extensive and expensive broodstock conditioning. © 2013 Elsevier B.V.
Matias D.,Instituto Portugues do Mar e Atmosfera |
Matias D.,CIIMAR – Interdisciplinary Center of Marine and Environmental |
Joaquim S.,Instituto Portugues do Mar e Atmosfera |
Joaquim S.,CIIMAR – Interdisciplinary Center of Marine and Environmental |
And 2 more authors.
Invertebrate Reproduction and Development | Year: 2016
Ruditapes decussatus is a species of importance to aquaculture. For hatcheries to consistently produce spat it is essential to develop broodstock conditioning techniques. Food and temperature are the main factors that regulate the timing and rate of energy storage and reproduction in bivalves. This study was designed to evaluate the effects of different diets and temperatures on reproductive output of R. decussatus and express the evolution of the different lipid classes during sexual maturation. Broodstock clams were conditioned at 20 ± 1 °C under four nutritional regimes: unfed, two mono-specific diets, Isochrysis galbana clone T-ISO and Chaetoceros calcitrans and, a mixture of these microalgae. Another group of clams was conditioned at 22 ± 1 °C and was fed the same mixture of microalgae. Gametogenesis, energy storage and spawning success were all influenced by the nutritional value of the diet received, as evidenced by the differences in reproductive effort among the single and combined supplemental diets. Temperature must be carefully managed to improve the reproductive conditioning of bivalves: high temperature throughout gametogenesis shortens the time to full ripeness but does not produce better reproductive output. The combination diet at 20 ± 1 °C is best for R. decussatus broodstock conditioning. © 2016 Taylor & Francis
PubMed | Instituto Portugues do Mar e Atmosfera
Type: | Journal: Marine environmental research | Year: 2012
The Water Framework Directives aims a reduction in concentration of hazardous substances in the marine environment. Consequently, there is a need to distinguish between anthropogenically influenced metal concentrations from natural background levels. To better achieve this goal in the Portuguese coast, dissolved and particulate trace metal (TM) concentrations along the Portuguese coast were determined in 46 sites distance 1-3 km from the shoreline. Dissolved values ranged within the following intervals: 0.01-0.89 nM for Cd, 0.01-3.37 nM for Co, 0.90-45.4 nM for Cu, 3.30-140 pM for Hg, 1.88-15.1 nM for Ni, 0.01-0.15 nM for Pb and 1.40-62.0 nM for Zn. Whereas Cd, Co, Cu, Ni and Zn were enhanced in the southern coast, while Pb values were higher in the central part of the western coast. Mercury concentrations showed punctual increases all along the coast. Values of trace metals in suspended particulate matter varied in a broad range: 36-2902 mol g(-1) for Al, 0.10-15.1 nmol g(-1) for Cd, 1.50-165 nmol g(-1) for Co, 50.0-990 nmol g(-1) for Cu, 2.80-76.4 nmol g(-1) for Hg, 22-1471 nmol g(-1) for Ni, 10.0-347 nmol g(-1) for Pb and 416-10,981 nmol g(-1) for Zn. Higher values for Al, Ni and Co were found in the central part of the western coast. However, Cd, Cu, Pb and Zn increased their levels from the north coast towards the central and south areas. The variability of both dissolved and particulate metals appears to be mainly associated with oceanographic conditions and continental inputs at North and central areas of the coast, and in the south coast to geological features rather than to anthropogenic pressures. On the basis of these results, regional baseline concentrations are proposed for the three typologies in Portuguese coastal waters defined under the Water Framework Directive.