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Andone Estonba - One of the best experts on this subject based on the ideXlab platform.
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New SNP markers in European Anchovy and albacore: useful genetic tools for stock delimitation
Instrumentation viewpoint, 2013Co-Authors: Urtzi Laconcha, Iratxe Montes, Haritz Arrizabalaga, Andone EstonbaAbstract:Albacore and European Anchovy fisheries require a management regime based on integral information. Genetic markers like SNPs are elementary for this purpose. In this paper, newly discovered SNPs in both species and their utility for stock delimitation is described.
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snp discovery in European Anchovy engraulis encrasicolus l by high throughput transcriptome and genome sequencing
PLOS ONE, 2013Co-Authors: Iratxe Montes, Darrell Conklin, Aitor Albaina, Simon Creer, Gary R Carvalho, Maria Jose Santos, Andone EstonbaAbstract:Increased throughput in sequencing technologies has facilitated the acquisition of detailed genomic information in non-model species. The focus of this research was to discover and validate SNPs derived from the European Anchovy (Engraulis encrasicolus) transcriptome, a species with no available reference genome, using next generation sequencing technologies. A cDNA library was constructed from four tissues of ten fish individuals corresponding to three populations of E. encrasicolus, and Roche 454 GS FLX Titanium sequencing yielded 19,367 contigs. Additionally, the European Anchovy genome was sequenced for the same ten individuals using an Illumina HiSeq2000. Using a computational pipeline for combining transcriptome and genome information, a total of 18,994 SNPs met the necessary minor allele frequency and depth filters. A series of further stringent filters were applied to identify those SNPs likely to succeed in genotyping assays, and for filtering of those in potential duplicated genome regions. A novel method for detecting potential intron-exon boundaries in areas of putative SNPs has also been applied in silico to improve genotyping success. In all, 2,317 filtered putative transcriptome SNPs suitable for genotyping primer design were identified. From those, a subset of 530 were selected, with the genotyping results showing the highest reported conversion and validation rates (91.3% and 83.2%, respectively) reported to date for a non-model species. This study represents a promising strategy to discover genotypable SNPs in the exome of non-model organisms. The genomic resource generated for E. encrasicolus, both in terms of sequences and novel markers, will be informative for research into this species with applications including traceability studies, population genetic analyses and aquaculture.
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multiple snp markers reveal fine scale population and deep phylogeographic structure in European Anchovy engraulis encrasicolus l
PLOS ONE, 2012Co-Authors: Iratxe Zarraonaindia, Mikel Iriondo, Carmen Manzano, Miguel Angel Pardo, Aitor Albaina, Xabier Irigoien, Stewart W Grant, Andone EstonbaAbstract:Geographic surveys of allozymes, microsatellites, nuclear DNA (nDNA) and mitochondrial DNA (mtDNA) have detected several genetic subdivisions among European Anchovy populations. However, these studies have been limited in their power to detect some aspects of population structure by the use of a single or a few molecular markers, or by limited geographic sampling. We use a multi-marker approach, 47 nDNA and 15 mtDNA single nucleotide polymorphisms (SNPs), to analyze 626 European anchovies from the whole range of the species to resolve shallow and deep levels of population structure. Nuclear SNPs define 10 genetic entities within two larger genetically distinctive groups associated with oceanic variables and different life-history traits. MtDNA SNPs define two deep phylogroups that reflect ancient dispersals and colonizations. These markers define two ecological groups. One major group of Iberian-Atlantic populations is associated with upwelling areas on narrow continental shelves and includes populations spawning and overwintering in coastal areas. A second major group includes northern populations in the North East (NE) Atlantic (including the Bay of Biscay) and the Mediterranean and is associated with wide continental shelves with local larval retention currents. This group tends to spawn and overwinter in oceanic areas. These two groups encompass ten populations that differ from previously defined management stocks in the Alboran Sea, Iberian-Atlantic and Bay of Biscay regions. In addition, a new North Sea-English Channel stock is defined. SNPs indicate that some populations in the Bay of Biscay are genetically closer to North Western (NW) Mediterranean populations than to other populations in the NE Atlantic, likely due to colonizations of the Bay of Biscay and NW Mediterranean by migrants from a common ancestral population. Northern NE Atlantic populations were subsequently established by migrants from the Bay of Biscay. Populations along the Iberian-Atlantic coast appear to have been founded by secondary waves of migrants from a southern refuge.
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microsatellite variability in European Anchovy engraulis encrasicolus calls for further investigation of its genetic structure and biogeography
Ices Journal of Marine Science, 2009Co-Authors: Iratxe Zarraonaindia, Carmen Manzano, Mikel Iriondo, Miguel Angel Pardo, Andone EstonbaAbstract:Zarraonaindia, I., Pardo, M. A., Iriondo, M., Manzano, C., and Estonba, A. 2009. Microsatellite variability in European Anchovy (Engraulis encrasicolus) calls for further investigation of its genetic structure and biogeography. – ICES Journal of Marine Science, 66: 000– 000. Attention to genetic and ecological perspectives can enhance strategies for using fishery resources sustainably. A potentially important application is the use of molecular markers to assess the genetic stock structure of a harvested species. In this study, seven microsa
Gualtiero Basilone - One of the best experts on this subject based on the ideXlab platform.
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First annulus formation in the European Anchovy; a two-stage approach for robust validation
Scientific Reports, 2020Co-Authors: Gualtiero Basilone, Salvatore Aronica, Ignazio Fontana, Gabriele Giacalone, Marco Barra, Rosalia Ferreri, Salvatore Mangano, Maurizio Pulizzi, Antonella Gargano, P. RumoloAbstract:The age determination in fast-growing short-living species, such as European Anchovy (Engraulis encrasicolus), has been widely recognized as a difficult task and bias introduced by readers leads to bias in reconstructing the population age structure. In this context, it is worth to note that age structure of fish population represents key information in fishery ecology and for stock assessment models. The uncertainty in estimating the age of the European Anchovy by otolith reading is linked to the number of false-growth increments (checks) laid down before the annulus formation. While direct validation methods (e.g. mark-recapture, rearing, radiochemical dating) are difficult to implement specially for this short living species, the use of different indirect methods, supported by a coherent statistical approach, represents a robust and easier validation tool. A statistical modeling approach has been here adopted to assess the coherence of two well-known methods, namely Edge Analysis and Marginal Increment Analysis, in order to validate the first annulus formation in European Anchovy. Both methodologies in two different yearly cycles converged toward the same result, thus confirming the annulus identification for the first year class. In addition, the completion dates of the checks and the first annulus were computed in order to gain a better insight into otolith growth dynamic. According to the species spawning period, the completion date of the first annulus falls in the summer period, while the first and second checks completion dates were mostly found in summer and winter respectively. General additive models using marginal increments as dependent variable showed a significant effect of the month, highlighting the presence of only one clear minimum in July/August, as well as specific relationships with condition factor and gonadosomatic index. Modeling the otolith edge morphology, the probability to find a hyaline band displayed in both years a similar shape, characterized by a minimum in July/August and higher values between November and January. The obtained results evidenced temporally coherent patterns providing a better insight in the otolith growth dynamic as well as a more robust validation of the first annulus formation in the European Anchovy.
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Spawning ecology of the European Anchovy (Engraulis encrasicolus) in the Strait of Sicily: Linking variations of zooplankton prey, fish density, growth, and reproduction in an upwelling system
Progress in Oceanography, 2020Co-Authors: Gualtiero Basilone, Ignazio Fontana, Angelo Bonanno, Gabriele Giacalone, Marco Barra, Rosalia Ferreri, Maurizio Pulizzi, Antonella Gargano, P. Rumolo, Salvatore MazzolaAbstract:Abstract A 12-year time series (2005–2016) was examined to explore relationships between European Anchovy density, growth, reproduction and habitat dynamics in an upwelling system. Specifically, data used for a daily egg production method were combined with oceanographic data, prey availability, as well as acoustic surveys of the Anchovy stock in the Strait of Sicily, in the Central Mediterranean Sea. Variables typically used for evaluating habitat dynamics (i.e. water temperature, chlorophyll-a, zooplankton concentration, kinetic energy, mixed layer depth and upwelling index) indicated strong upwelling events during the summer, when Anchovy spawns. A linear ‘principal component’ combination of environmental traits, associated with summer upwelling, was identified by step-wise regression as a driver for growth (length at the end of the first year; L1), reproductive investment (gonad-somatic index; GSI), as well as egg production (daily specific fecundity; DSF). These relationships are consistent with direct energy flow from the environment to both somatic growth and reproductive output, indicating an income breeding strategy by Anchovy (i.e. surplus energy acquired during the summer breeding season is used directly for reproductive growth). Step-wise regression also identified three additional relationships: (1) a density-dependent mechanism reducing growth (L1) and fecundity (DSF) at higher fish densities; (2) higher fish condition (Kn) positively affecting growth (L1); (3) higher prey availability (mesozooplankton concentration) positively affecting GSI. This time series and approach are promising for exploring the abiotic and biotic mechanisms setting year class strength in advance of recruitment to the fishery.
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Effects of habitat conditions at hatching time on growth history of offspring European Anchovy, Engraulis encrasicolus, in the Central Mediterranean Sea
Hydrobiologia, 2018Co-Authors: Gualtiero Basilone, Ignazio Fontana, Gabriele Giacalone, Marco Barra, Rosalia Ferreri, Salvatore Mangano, Maurizio Pulizzi, Antonella Gargano, Salvatore Mazzola, Simona GenoveseAbstract:The knowledge of the growth history in young fishes represents an important aspect of fishery ecology. This is especially relevant in short-living species like European Anchovy, since they suffer a high mortality rate in their early life stages until recruitment. Although it is well known that habitat condition significantly affects spawning dynamics of fishes, it is not yet clear if these conditions affect growth trajectories during the early life stage’s critical period. Otolith microstructure analysis has been proven a useful tool to back-calculate growth history of young fishes. Thus, we analysed the effect of habitat variability on their growth history using otolith microstructures and environmental variables obtained from satellite imagery. Growth trajectories in juvenile anchovies, collected in two recruitment surveys carried out in 2004 and 2005 in the Strait of Sicily, were characterized by means of three indices within the fast growing period: the maximum increment width, the mean value of increment width, and the time extension of the fast growing period. Obtained results evidenced a clear effect of environmental conditions, particularly of sea surface temperature and chlorophyll-a concentration, on the growth histories of juveniles of Anchovy. Furthermore, delayed effects of environmental conditions at hatching time on the forthcoming growth dynamics were discussed.
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Liver melanomacrophage centres and CYP1A expression as response biomarkers to environmental pollution in European Anchovy (Engraulis encrasicolus) from the western Mediterranean Sea.
Marine Pollution Bulletin, 2018Co-Authors: Gualtiero Basilone, Rosalia Ferreri, Salvatore Mangano, Maurizio Pulizzi, Antonella Gargano, Salvatore Mazzola, Aldo Corriero, R. Zupa, N. Santamaria, Angelo BonannoAbstract:Abstract The goal of the present study was to verify the suitability of using melanomacrophage centres (MMCs) as response biomarkers of marine pollution in European Anchovy, which are short-lived, migratory, small pelagic fish. This suitability was verified by analysing the MMC density and cytochrome P450 monooxygenase 1A (CYP1A) expression in livers of anchovies from four areas of southern Italy. Age 2 anchovies sampled from three areas exposed to pollutants of industrial/agricultural origin (Gulf of Gela, Mazara del Vallo and Gulf of Naples) showed liver areas occupied by MMCs and numbers of MMCs that were significantly higher than those in the anchovies from Pozzallo, which is a marine area not subjected to any source of pollution. Anti-CYP1A immunoreactivity was observed in the hepatocytes of all specimens sampled from the Gulf of Gela. These findings suggest the utility of liver MMCs as biomarkers of exposure to pollutants in this small pelagic fish.
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European Anchovy (Engraulis encrasicolus) age structure and growth rate in two contrasted areas of the Mediterranean Sea: the paradox of faster growth in oligotrophic seas
Mediterranean Marine Science, 2017Co-Authors: Gualtiero Basilone, Salvatore Aronica, Ignazio Fontana, Gabriele Giacalone, Marco Barra, Rosalia Ferreri, Salvatore Mangano, Maurizio Pulizzi, Antonella Gargano, Simona GenoveseAbstract:Fishery production is highly dependent on fish growth and environmental factors; primary production and temperature are the two most important variables affecting almost all biological rates, especially individual growth or population production rate. The growth of European Anchovy, Engraulis encrasicolus , was compared between two populations inhabiting different ecosystems: the Tyrrhenian Sea, characterized by riverine inputs and the Strait of Sicily, an oligotrophic area. The effects of habitat conditions on growth was also evaluated using literature data on other of European Anchovy populations. Water temperature was confirmed to be a determinant factor for Anchovy growth at the species level positively affecting the length at age-1. On the contrary, a negative relationship was found between chlorophyll-a and the length at age-1. These findings suggested that size at age-1 is strongly dependent on habitat conditions. The age structure differed significantly between the two populations, with the Tyrrhenian stock dominated by age-1 fish.
Salvatore Mazzola - One of the best experts on this subject based on the ideXlab platform.
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Spawning ecology of the European Anchovy (Engraulis encrasicolus) in the Strait of Sicily: Linking variations of zooplankton prey, fish density, growth, and reproduction in an upwelling system
Progress in Oceanography, 2020Co-Authors: Gualtiero Basilone, Ignazio Fontana, Angelo Bonanno, Gabriele Giacalone, Marco Barra, Rosalia Ferreri, Maurizio Pulizzi, Antonella Gargano, P. Rumolo, Salvatore MazzolaAbstract:Abstract A 12-year time series (2005–2016) was examined to explore relationships between European Anchovy density, growth, reproduction and habitat dynamics in an upwelling system. Specifically, data used for a daily egg production method were combined with oceanographic data, prey availability, as well as acoustic surveys of the Anchovy stock in the Strait of Sicily, in the Central Mediterranean Sea. Variables typically used for evaluating habitat dynamics (i.e. water temperature, chlorophyll-a, zooplankton concentration, kinetic energy, mixed layer depth and upwelling index) indicated strong upwelling events during the summer, when Anchovy spawns. A linear ‘principal component’ combination of environmental traits, associated with summer upwelling, was identified by step-wise regression as a driver for growth (length at the end of the first year; L1), reproductive investment (gonad-somatic index; GSI), as well as egg production (daily specific fecundity; DSF). These relationships are consistent with direct energy flow from the environment to both somatic growth and reproductive output, indicating an income breeding strategy by Anchovy (i.e. surplus energy acquired during the summer breeding season is used directly for reproductive growth). Step-wise regression also identified three additional relationships: (1) a density-dependent mechanism reducing growth (L1) and fecundity (DSF) at higher fish densities; (2) higher fish condition (Kn) positively affecting growth (L1); (3) higher prey availability (mesozooplankton concentration) positively affecting GSI. This time series and approach are promising for exploring the abiotic and biotic mechanisms setting year class strength in advance of recruitment to the fishery.
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Effects of habitat conditions at hatching time on growth history of offspring European Anchovy, Engraulis encrasicolus, in the Central Mediterranean Sea
Hydrobiologia, 2018Co-Authors: Gualtiero Basilone, Ignazio Fontana, Gabriele Giacalone, Marco Barra, Rosalia Ferreri, Salvatore Mangano, Maurizio Pulizzi, Antonella Gargano, Salvatore Mazzola, Simona GenoveseAbstract:The knowledge of the growth history in young fishes represents an important aspect of fishery ecology. This is especially relevant in short-living species like European Anchovy, since they suffer a high mortality rate in their early life stages until recruitment. Although it is well known that habitat condition significantly affects spawning dynamics of fishes, it is not yet clear if these conditions affect growth trajectories during the early life stage’s critical period. Otolith microstructure analysis has been proven a useful tool to back-calculate growth history of young fishes. Thus, we analysed the effect of habitat variability on their growth history using otolith microstructures and environmental variables obtained from satellite imagery. Growth trajectories in juvenile anchovies, collected in two recruitment surveys carried out in 2004 and 2005 in the Strait of Sicily, were characterized by means of three indices within the fast growing period: the maximum increment width, the mean value of increment width, and the time extension of the fast growing period. Obtained results evidenced a clear effect of environmental conditions, particularly of sea surface temperature and chlorophyll-a concentration, on the growth histories of juveniles of Anchovy. Furthermore, delayed effects of environmental conditions at hatching time on the forthcoming growth dynamics were discussed.
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Liver melanomacrophage centres and CYP1A expression as response biomarkers to environmental pollution in European Anchovy (Engraulis encrasicolus) from the western Mediterranean Sea.
Marine Pollution Bulletin, 2018Co-Authors: Gualtiero Basilone, Rosalia Ferreri, Salvatore Mangano, Maurizio Pulizzi, Antonella Gargano, Salvatore Mazzola, Aldo Corriero, R. Zupa, N. Santamaria, Angelo BonannoAbstract:Abstract The goal of the present study was to verify the suitability of using melanomacrophage centres (MMCs) as response biomarkers of marine pollution in European Anchovy, which are short-lived, migratory, small pelagic fish. This suitability was verified by analysing the MMC density and cytochrome P450 monooxygenase 1A (CYP1A) expression in livers of anchovies from four areas of southern Italy. Age 2 anchovies sampled from three areas exposed to pollutants of industrial/agricultural origin (Gulf of Gela, Mazara del Vallo and Gulf of Naples) showed liver areas occupied by MMCs and numbers of MMCs that were significantly higher than those in the anchovies from Pozzallo, which is a marine area not subjected to any source of pollution. Anti-CYP1A immunoreactivity was observed in the hepatocytes of all specimens sampled from the Gulf of Gela. These findings suggest the utility of liver MMCs as biomarkers of exposure to pollutants in this small pelagic fish.
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Application of GAMs and multinomial models to assess the spawning pattern of fishes with daily spawning synchronicity: A case study in the European Anchovy (Engraulis encrasicolus) in the central Mediterranean Sea
Fisheries Research, 2015Co-Authors: Gualtiero Basilone, Rosalia Ferreri, M. D’elia, Salvatore Mazzola, Konstantinos Ganias, Enza Maria Quinci, A. BonannoAbstract:Abstract Information on the breeding behaviour of fish such as spatial segregation phenomena during spawning events is important both for understanding their reproductive ecology but also for correctly designing sampling schemes in stock assessment. The daily spawning pattern of the European Anchovy, Engraulis encrasicolus , was assessed using a novel methodology that included the analysis of the hourly distribution of imminent and recent spawning stages using a combination of generalised additive models (GAMs) and of multinomial models for ordinal categorical data. To do so we used data from nine years of daily egg production method, DEPM, surveys, carried out in the Strait of Sicily. The spatial distribution and occurrence of actively spawning individuals were also analysed. Results showed that the actively spawning phase period (ASPP), i.e., the period from the onset of oocyte hydration to spawning ranged approximately 4.5 h between ca. 18:30 and 23:00 while a daily spawning peak was identified at 22:30. The sex ratio was skewed during the ASPP such that females exceeded males by ca. 20% at mid ASPP. During the ASPP the proportion of Day-0 females (i.e., females that spawned or would spawn the day of sampling) decreases with increasing bottom depth while outside the ASPP Day-0 spawners did not show any particular bathymetric pattern. In the study area, anchovies exhibit segregative spawning behaviour which drives spawners to select shallower waters, similar to other Anchovy populations in the Mediterranean while in the Atlantic and in other clupeoid populations the opposite bathymetric trend has been observed.
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spawning site selection by European Anchovy engraulis encrasicolus in relation to oceanographic conditions in the strait of sicily
Fisheries Oceanography, 2013Co-Authors: Gualtiero Basilone, Angelo Bonanno, Marco Barra, Angela Cuttitta, Salvatore Mazzola, B Patti, Richard S McbrideAbstract:European Anchovy egg occurrence and density data from summer surveys (1998–2007) and oceanographic data were examined to study the mechanisms that control the spatial distribution of Anchovy spawning habitat in the Strait of Sicily. Quotient analysis indicated habitat preference for temperature (18–19°C), bottom depth (50–100 m), water column stability (13–14 cycle h−1), fluorescence (0.10–0.15 μg m−3 Chl a), salinity (37.5–37.6 PSU), current speed (0.20–0.25 m s−1) and density (26.7–26.8 kg m−3, σt). Canonical discriminant analysis identified temperature, column stability and fluorescence as major drivers of Anchovy spawning habitat. Three of the 4 years which had lower egg abundance were warmer years, with low values of primary productivity. A geostrophic current flowing through the Strait (the Atlantic Ionic Stream, AIS) was confirmed as the main source of environmental variability in structuring the Anchovy spawning ground by its influence on both the oceanography and distribution of Anchovy eggs. This 10-yr data series demonstrates recurrent but also variable patterns of oceanographic flows and egg distribution. A lack of freshwater flow in this area appears to depress productivity in the region, but certain and variable combinations of environmental conditions can elevate production in some sub-areas in most years or other sub-areas in fewer years. These temporal and spatial patterns are consistent with an ocean triad theory postulating that processes of oceanographic enrichment, concentration, and retention may help predict fishery yields.
Olivier Thébaud - One of the best experts on this subject based on the ideXlab platform.
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A dynamic model of the Bay of Biscay pelagic fleet simulating fishing trip choice: the response to the closure of the European Anchovy (Engraulis encrasicolus) fishery in 2005
Canadian Journal of Fisheries and Aquatic Sciences, 2008Co-Authors: Youen Vermard, Paul Marchal, Stéphanie Mahévas, Olivier ThébaudAbstract:The scope of this paper is to describe, evaluate, and forecast fishing trip choices of the Bay of Biscay pelagic fleet using random utility modeling (RUM). First, alternative fishing trip choices of this fleet were identified using multivariate statistical methods based on species landings weighted by value and defined as distinct fishing activity or fisheries (termed métiers). A RUM was specified, which included trip components as attributes during the period 2001-2004 (a lagged percentage of the value per unit of effort of the main species caught, total value per unit of effort, and inertia in terms of changes from one métier to another). For the main métiers, the proportion of correct effort allocation is 90% during the calibration period of 2001-2004. The results from the RUM are used to parameterize a simulation model of trip choice. The model is used to predict trip choices in 2005, throughout most of which fishing was constrained by the closure of the European Anchovy (Engraulis encrasicolus) fishery. Simulation results are compared with observed trip choices following the fishing ban: 80% of observed trip choices are correctly predicted by the model. The capacity of the behavioral model to predict responses to the closure is then discussed.
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a dynamic model of the bay of biscay pelagic fleet simulating fishing trip choice the response to the closure of the European Anchovy engraulis encrasicolus fishery in 2005
Post-Print, 2008Co-Authors: Youen Vermard, Paul Marchal, Stéphanie Mahévas, Olivier ThébaudAbstract:The scope of this paper is to describe, evaluate, and forecast fishing trip choices of the Bay of Biscay pelagic fleet using random utility modeling (RUM). First, alternative fishing trip choices of this fleet were identified using multivariate statistical methods based on species landings weighted by value and defined as distinct fishing activity or fisheries (termed metiers). A RUM was specified, which included trip components as attributes during the period 2001-2004 (a lagged percentage of the value per unit of effort of the main species caught, total value per unit of effort, and inertia in terms of changes from one metier to another). For the main metiers, the proportion of correct effort allocation is 90% during the calibration period of 2001-2004. The results from the RUM are used to parameterize a simulation model of trip choice. The model is used to predict trip choices in 2005, throughout most of which fishing was constrained by the closure of the European Anchovy (Engraulis encrasicolus) fishery. Simulation results are compared with observed trip choices following the fishing ban: 80% of observed trip choices are correctly predicted by the model. The capacity of the behavioral model to predict responses to the closure is then discussed.
Angelo Bonanno - One of the best experts on this subject based on the ideXlab platform.
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Spawning ecology of the European Anchovy (Engraulis encrasicolus) in the Strait of Sicily: Linking variations of zooplankton prey, fish density, growth, and reproduction in an upwelling system
Progress in Oceanography, 2020Co-Authors: Gualtiero Basilone, Ignazio Fontana, Angelo Bonanno, Gabriele Giacalone, Marco Barra, Rosalia Ferreri, Maurizio Pulizzi, Antonella Gargano, P. Rumolo, Salvatore MazzolaAbstract:Abstract A 12-year time series (2005–2016) was examined to explore relationships between European Anchovy density, growth, reproduction and habitat dynamics in an upwelling system. Specifically, data used for a daily egg production method were combined with oceanographic data, prey availability, as well as acoustic surveys of the Anchovy stock in the Strait of Sicily, in the Central Mediterranean Sea. Variables typically used for evaluating habitat dynamics (i.e. water temperature, chlorophyll-a, zooplankton concentration, kinetic energy, mixed layer depth and upwelling index) indicated strong upwelling events during the summer, when Anchovy spawns. A linear ‘principal component’ combination of environmental traits, associated with summer upwelling, was identified by step-wise regression as a driver for growth (length at the end of the first year; L1), reproductive investment (gonad-somatic index; GSI), as well as egg production (daily specific fecundity; DSF). These relationships are consistent with direct energy flow from the environment to both somatic growth and reproductive output, indicating an income breeding strategy by Anchovy (i.e. surplus energy acquired during the summer breeding season is used directly for reproductive growth). Step-wise regression also identified three additional relationships: (1) a density-dependent mechanism reducing growth (L1) and fecundity (DSF) at higher fish densities; (2) higher fish condition (Kn) positively affecting growth (L1); (3) higher prey availability (mesozooplankton concentration) positively affecting GSI. This time series and approach are promising for exploring the abiotic and biotic mechanisms setting year class strength in advance of recruitment to the fishery.
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Liver melanomacrophage centres and CYP1A expression as response biomarkers to environmental pollution in European Anchovy (Engraulis encrasicolus) from the western Mediterranean Sea.
Marine Pollution Bulletin, 2018Co-Authors: Gualtiero Basilone, Rosalia Ferreri, Salvatore Mangano, Maurizio Pulizzi, Antonella Gargano, Salvatore Mazzola, Aldo Corriero, R. Zupa, N. Santamaria, Angelo BonannoAbstract:Abstract The goal of the present study was to verify the suitability of using melanomacrophage centres (MMCs) as response biomarkers of marine pollution in European Anchovy, which are short-lived, migratory, small pelagic fish. This suitability was verified by analysing the MMC density and cytochrome P450 monooxygenase 1A (CYP1A) expression in livers of anchovies from four areas of southern Italy. Age 2 anchovies sampled from three areas exposed to pollutants of industrial/agricultural origin (Gulf of Gela, Mazara del Vallo and Gulf of Naples) showed liver areas occupied by MMCs and numbers of MMCs that were significantly higher than those in the anchovies from Pozzallo, which is a marine area not subjected to any source of pollution. Anti-CYP1A immunoreactivity was observed in the hepatocytes of all specimens sampled from the Gulf of Gela. These findings suggest the utility of liver MMCs as biomarkers of exposure to pollutants in this small pelagic fish.
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spawning site selection by European Anchovy engraulis encrasicolus in relation to oceanographic conditions in the strait of sicily
Fisheries Oceanography, 2013Co-Authors: Gualtiero Basilone, Angelo Bonanno, Marco Barra, Angela Cuttitta, Salvatore Mazzola, B Patti, Richard S McbrideAbstract:European Anchovy egg occurrence and density data from summer surveys (1998–2007) and oceanographic data were examined to study the mechanisms that control the spatial distribution of Anchovy spawning habitat in the Strait of Sicily. Quotient analysis indicated habitat preference for temperature (18–19°C), bottom depth (50–100 m), water column stability (13–14 cycle h−1), fluorescence (0.10–0.15 μg m−3 Chl a), salinity (37.5–37.6 PSU), current speed (0.20–0.25 m s−1) and density (26.7–26.8 kg m−3, σt). Canonical discriminant analysis identified temperature, column stability and fluorescence as major drivers of Anchovy spawning habitat. Three of the 4 years which had lower egg abundance were warmer years, with low values of primary productivity. A geostrophic current flowing through the Strait (the Atlantic Ionic Stream, AIS) was confirmed as the main source of environmental variability in structuring the Anchovy spawning ground by its influence on both the oceanography and distribution of Anchovy eggs. This 10-yr data series demonstrates recurrent but also variable patterns of oceanographic flows and egg distribution. A lack of freshwater flow in this area appears to depress productivity in the region, but certain and variable combinations of environmental conditions can elevate production in some sub-areas in most years or other sub-areas in fewer years. These temporal and spatial patterns are consistent with an ocean triad theory postulating that processes of oceanographic enrichment, concentration, and retention may help predict fishery yields.
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characterizing the potential habitat of European Anchovy engraulis encrasicolus in the mediterranean sea at different life stages
Fisheries Oceanography, 2013Co-Authors: Marianna Giannoulaki, Angelo Bonanno, Iole Leonori, B Patti, M Iglesias, M P Tugores, A De Felice, Jeanlouis Bigot, Vjekoslav Ticina, Mariamyrto PyrounakiAbstract:Identification of the potential habitat of European Anchovy (Engraulis encrasicolus) at different life stages in relation to environmental conditions is an interesting subject from both ecological and management points of view. For this purpose, acoustic data from different seasons and different parts of the Mediterranean Sea along with satellite environmental and bathymetry data were modelled using generalized additive models. Similarly, egg distribution data from summer ichthyoplankton surveys were used to model potential spawning habitat. Selected models were used to produce maps presenting the probability of Anchovy presence (adults, juveniles and eggs) in the entire Mediterranean basin, as a measure of habitat adequacy. Bottom depth and sea surface chlorophyll concentration were the variables found important in all models. Potential Anchovy habitats were located over the continental shelf for all life stages examined. An expansion of the potential habitat from the peak spawning (early summer) to the late spawning season (early autumn) was observed. However, the most suitable areas for the presence of Anchovy spawners seem to maintain the same size between seasons. Potential juvenile habitats were associated with highly productive inshore waters, being less extended and closer to coast during winter than late autumn. Potential spawning habitat in June and July based on ichthyoplankton surveys overlapped but were wider in extent compared with adult potential habitat from acoustics in the same season. Similarities and dissimilarities between the Anchovy habitats as well as comparisons with sardine habitats in the oligotrophic Mediterranean Sea and other ecosystems with higher productivity are discussed.
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Linking air-sea energy exchanges and European Anchovy potential spawning ground
European Physical Journal B, 2008Co-Authors: Rosario Grammauta, Diego Molteni, Salvatore Aronica, Ignazio Fontana, Muammer Zora, Cástor Guisande, Gualtiero Basilone, Angelo Bonanno, Gabriele Giacalone, Bernardo PattiAbstract:The physical and chemical processes of the sea greatly affect the reproductive biology of fishes, mainly influencing both the numbers of spawned eggs and the survivorship of early stages up to the recruitment period. In the central Mediterranean, the European Anchovy constitutes one of the most important fishery resource. Because of its short living nature and of its recruitment variability, associated to high environmental variability, this small pelagic species undergo high interannual fluctuation in the biomass levels. Despite several efforts were addressed to characterize fishes spawning habitat from the oceanographic point of view, very few studies analyze the air-sea exchanges effects. To characterize the spawning habitat of these resources a specific technique (quotient rule analysis) was applied on air-sea heat fluxes, wind stress, sea surface temperature and turbulence data, collected in three oceanographic surveys during the summer period of 2004, 2005 and 2006. The results showed the existence of preferred values in the examined physical variables, associated to Anchovy spawning areas. Namely, for heat fluxes the values were around −40 W/m2, for wind stress 0.04–0.11 N/m2, for SST 23°C, and 300 − 500 m3s−3 for wind mixing. Despite the obtained results are preliminary, this is the first relevant analysis on the air-sea exchanges and their relationship with the fish biology of pelagic species.
