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In this study, fifteen morphometric and nine meristic traits have been examined of the Scorpaena scrofa, Scorpaena elongata, Scorpaena notata, and Helicolenus dactylopterus species from the Antalya Bay. The results showed that the S. scrofa total length ranged from 109.29 to 271.12 mm and was characterized by dark spots on its spinous dorsal spines between the 6th and 11th. In the S. elongata total length was 153.61 to 248.67 mm. On the other hand, S. notata is characterized by a total length of 131.28 to 305.24 mm and supraocular tentacle. In the H. dactylopterus total length was 110.87 to 306.23 mm. The linear length-length relationships and the allometric growth pattern were also investigated. For all species, correlations between fifteen different morphometric measurements showed a significant difference (p <0.05). R2 correlation coefficient was between 0.752 to 0.988 for the S. scrofa, 0.485 to 0.959 for the S. elongata, 0.207 to 0.975 for the S. notata, and, 0.417 to 0.926 for the H. dactylopterus, respectively. Thus, this study may provide useful information for the conservation and sustainable management of these important fish species. [ABSTRACT FROM AUTHOR]

The study evaluated the effect of two animal protein-free extenders on ram semen cryopreservation of two tropical hair breeds. The ejaculates were collected from 8 rams (4 Blackbelly and 4 Pelibuey), which were mixed (pooled) by breed, diluted and cryopreserved in three different extenders: Animal protein [Tris egg yolk (Triladyl®)], and animal protein-free extenders AndroMed® (lecithin soy bean) and OPTIXcell® (liposome). Sperm analyses of total (TM) and progressive (PM) motility, viability, mitochondrial activity, acrosome integrity, and plasma membrane integrity (PMI) were carried out at 0 and 6 h after semen thawing. OPTIXcell® and Triladyl® extenders showed similar results between them and differed with AndroMed® in TM, PM, viability, and PMI (P < 0.0017). In the Blackbelly breed, the TM was higher (P < 0.0159) in OPTIXcell® than in AndroMed®. In the Pelibuey breed, the OPTIXcell® and Triladyl® showed similar results between them and differed with AndroMed® in TM, PM, viability, mitochondrial activity, and PMI (P < 0.0140). However, Triladyl® showed a higher percentage of sperm with intact acrosome than AndroMed® (P < 0.0392). In both breeds, spermatic parameters decreased progressively over the incubation time similarly in all three extenders. In conclusion, OPTIXcell® and Triladyl® proved to be the best extenders to cryopreserve Blackbelly and Pelibuey ram semen. However, OPTIXcell® is an animal protein-free extender that decreases the risk of bacterial contamination, whereas Triladyl® is composed of animal protein (egg yolk), which may impact the fertilizing capacity of sperm. [ABSTRACT FROM AUTHOR]

Indices of abundance are usually a key input parameter used for fitting a stock assessment model, as they provide abundance estimates representative of the fraction of the stock that is vulnerable to fishing. These indices can be estimated from catches derived from fishery-dependent sources, such as catch per unit effort (CPUE) and landings per unit effort (LPUE), or from scientific survey data (e.g., relative population number—RPN). However, fluctuations in many factors (e.g., vessel size, period, area, gear) may affect the catch rates, bringing the need to evaluate the appropriateness of the statistical models for the standardization process. In this research, we analyzed different generalized linear models to select the best technique to standardize catch rates of target and non-target species from fishery dependent (CPUE and LPUE) and independent (RPN) data. The examined error distribution models were gamma, lognormal, tweedie, and hurdle models. For hurdle, positive observations were analyzed assuming a lognormal (hurdle–lognormal) or gamma (hurdle–gamma) error distribution. Based on deviance table analyses and diagnostic checks, the hurdle–lognormal was the statistical model that best satisfied the underlying characteristics of the different data sets. Finally, catch rates (CPUE, LPUE and RPN) of the thornback ray Raja clavata, blackbelly rosefish Helicolenus dactylopterus, and common mora Mora moro from the NE Atlantic (Azores region) were standardized. The analyses confirmed the spatial and temporal nature of their distribution.

Indices of abundance are usually a key input parameter used for fitting a stock assessment model, as they provide abundance estimates representative of the fraction of the stock that is vulnerable to fishing. These indices can be estimated from catches derived from fishery-dependent sources, such as catch per unit effort (CPUE) and landings per unit effort (LPUE), or from scientific survey data (e.g., relative population number—RPN). However, fluctuations in many factors (e.g., vessel size, period, area, gear) may affect the catch rates, bringing the need to evaluate the appropriateness of the statistical models for the standardization process. In this research, we analyzed different generalized linear models to select the best technique to standardize catch rates of target and non-target species from fishery dependent (CPUE and LPUE) and independent (RPN) data. The examined error distribution models were gamma, lognormal, tweedie, and hurdle models. For hurdle, positive observations were analyzed assuming a lognormal (hurdle–lognormal) or gamma (hurdle–gamma) error distribution. Based on deviance table analyses and diagnostic checks, the hurdle–lognormal was the statistical model that best satisfied the underlying characteristics of the different data sets. Finally, catch rates (CPUE, LPUE and RPN) of the thornback ray Raja clavata, blackbelly rosefish Helicolenus dactylopterus, and common mora Mora moro from the NE Atlantic (Azores region) were standardized. The analyses confirmed the spatial and temporal nature of their distribution. [ABSTRACT FROM AUTHOR]

This work presents a guidance to conduct stock assessment based on ICES Maximum Sustainable Yield framework. A cross-analysis based on the models' assumptions and inputs and data available for 22 Azorean priority stocks was performed to assess the applicability of each model to each stock. Information currently available for coastal and some demersal/deep-water stocks limits the use of most models validated by ICES. Only four demersal/deep-water stocks (Pagellus bogaraveo, Helicolenus dactylopterus, Phycis phycis, and Pontinus kuhlii) have data availability and quality enough to perform trend analysis, length-based and catch and survey-based methods. The next steps involve validating life-history parameters, evaluating model performances, and applying alternative tools for data-deficient stocks. Additional monitoring programs are of utmost importance, which must collect missing information and clarify stock delimitation to improve assessment quality. This study guides future stock assessment actions and highlights data gaps where future research should focus. [ABSTRACT FROM AUTHOR]

Abstract The bluemouth, Helicolenus dactylopterus (Delaroche 1809), is a marine demersal fish that is widely distributed in the Atlantic and the Mediterranean. It is targeted by longline fisheries around the Iberian Peninsula and it is a common by-catch associated with many demersal fisheries. However, limited information exists about the population structure in the NE Atlantic and Mediterranean. Thus, the bluemouth population structure in these regions was studied using a landmark-based geometric morphometric analysis. The purpose was to assess body shape variation among bluemouth and determine putative populations and their relationships. Three populations were identified in the western Mediterranean: two populations in the Alboran basin and another in the north-western basin (Balearic Sea and Catalonian coast). The population from the central Mediterranean did not seem to be effectively connected to the populations in the western Mediterranean. In the NE Atlantic, our results showed that at least four different bluemouth populations exist in the following areas: Galicia-Cantabrian Sea, Peniche (Portugal), the Gulf of Cadiz and the Porcupine Bank. A connection between bluemouth from the NE Atlantic and Mediterranean was observed, making unlikely that the Strait of Gibraltar acts as a barrier isolating Atlantic and Mediterranean bluemouth populations. The results of this study provide evidence that different bluemouth populations exist, which is relevant for stock assessment and management of this species. [ABSTRACT FROM AUTHOR]

Hamaticolax juanji n. sp. is described from specimens collected from the blackbelly rosefish Helicolenus dactylopterus Delaroche 1809 (Scorpaeniformes: Sebastidae). It is the second Hamaticolax species described and reported from the Mediterranean Sea, after Ha. resupinus Pérez-i-García, Carrassón and Boxshall, 2017. It is distinguished from Ha. resupinus by the presence of only one dorsal naked seta on the third segment of the antennule (vs. four), two unequal short naked setae in distal part of the antenna (vs. four), and the absence of a minute spine on the third endopodal segment of leg 1, among others. It is differentiated from Ha. prolixus Cressey 1969 by a comparatively reduced fourth pedigerous somite, the presence of two naked setae on the third segment of the antennule (vs. three), two naked setae and three curved claws in the distal part of the apical segment of the antenna (vs. three and four), an outer naked seta on the basis of leg 2, and by larger length/width ratio of the third endopodal segment, among others. Hamaticolax juanji n. sp. also has relatively longer inner setae on the first and second endopodal segments of leg 4 than the two former species. Patterns of host-use and host-specificity of the genus Hamaticolax are also discussed. The frequently observed low host-specificity of its members may be better explained by host ecological similarity and host availability phenomena, rather than by host phylogenetic distance. [ABSTRACT FROM AUTHOR]

Abstract Concentrations of 6 trace metals (Ag, Cd, Cu, Ni, Pb, Zn) in the muscle of 2 sharks (Galeus melastomus and Scyliorhinus canicula), 4 teleosts (Helicolenus dactylopterus , Lepidorhombus boscii , Micromesistius poutassou and Phycis blennoides) and 1 crustacean (Nephrops norvegicus) were compared between the Bay of Biscay (Atlantic Ocean) and the Gulf of Lions (Mediterranean Sea). Although average concentrations and the trace element pollution index were generally higher in the Gulf of Lions, significant differences between the two ecosystems were only found for Zn for Helicolenus dactylopterus , and for Ag and Cu for the crustacean N. norvegicus. Moreover, some relationships between trophic level or size and metal concentrations were found for these two species. The absence of clear pattern may result from the blurring effect of contamination and excretion that may act differentially for all species and all elements. Highlights • Low concentrations of trace metals in the muscle tissue for all studied marine species • Absence of clear patterns for all studied species and elements • Metal concentrations were mainly higher in the Gulf of Lions than in the Bay of Biscay. [ABSTRACT FROM AUTHOR]

Converging water masses and mesoscale eddies shape habitats for larval fish assemblages in upwelling ecosystems. In the Canary Current Upwelling Ecosystem, two water masses, the North Atlantic Central Water (NACW) and the South Atlantic Central Water (SACW) converge. The resulting Cape Verde Frontal Zone (CVFZ) is located off the Banc d'Arguin, Mauritania, an important nursery ground for fishes. We investigated the impact of two converging water masses and a mesoscale anticyclonic eddy on the composition and distribution of larval fish assemblages during an upwelling event. Two distinct larval fish assemblages allowed for the reconstruction of water mass distributions along the CVFZ. While the distribution pattern of Dicologlossa cuneata covered the shelf area in the North by NACW characteristics, Helicolenus dactylopterus , Bathylagoides argyrogaster , Hygophum macrochir , and Notoscopelus resplendens were almost exclusively observed in the offshore area in the South with SACW characteristics. This emergence of a dichotomy in larval fish assemblages was facilitated by the CVFZ and the mesoscale anticyclonic eddy, which retained fish larvae in SACW offshore. Coastal geostrophic currents on the other hand transported fish larvae from the North southward in NACW towards the Banc d'Arguin. The coastal geostrophic currents abetted an onshore surface water flow of upwelled water masses. This process facilitated a phytoplankton bloom on the Banc d'Arguin and possibly enabled a larval transport towards suitable nurseries. Our results have profound implications regarding the comprehension of hydrographical processes that govern the dispersal and retention of fish larvae. Our findings further shed light on the establishment of assemblages and the habitat expansion of fish larvae in upwelling ecosystems. [ABSTRACT FROM AUTHOR]

Summary: Present study evaluated the population status of the Bluemouth (Helicolenus dactylopterus) population distributed in the Antalya Bay for the first time, within the scope of two different surveys carried out in monthly basis, between September 2009 and June 2011 (200–900 m). In accordance with the major availability of the food, 80.9% of the total catch (in number) of the species at the upper slope (200–499 m). The 80.8% of all recruits’ specimens inhabits between 200 and 399 m while 72% of the total spawner specimens (TL ≥ 20 cm) inhabits at depths of between 600 and 799 m. Highest average abundance of the species was estimated 1,060 n/km2 (400 m), while the highest average biomass was 93 kg/km2 (600 m). Lengths of individuals ranged from 4 to 36 cm, and estimated ages from 0 to 27 years. Parameters of the von Bertalanffy growth curves were L∞ = 34.14 cm, K = 0.09 year−1, and t0 = −1.28 years. Margin band analysis confirmed the formation of a single growth annulus per year. In the central part of the otolith, close to the nucleus, a strongly marked check ring is formed which presenting first time for this species in the literature. The duration of the spawning stage for the females was observed between December and February. Selectivity rate of the commercially used 44 mm diamond codend mesh, with a 7.4 cm catch size, found to be very low for the species (a first spawning size of 17–20 cm). The stock of Bluemouth in the Antalya Bay was considered in above reference levels and in high abundance status due to estimated low fishing mortality (0.067−1), exploitation rate status below reference level (0.207−1) and Fcurr is very low than reference point (0.219−1). [ABSTRACT FROM AUTHOR]

Stock identification studies are essential to understanding fish population structure and connectivity across wide geographical areas, and thus contribute to efficient fisheries management. The blackbelly rosefish, Helicolenus dactylopterus , and European hake, Merluccius merluccius , are two economically important marine fishes, but there are still gaps in knowledge regarding their present stock structure. Our objective was to assess the ability of otolith shape to define stock structure for the two species along the Northeastern Atlantic Ocean and the Mediterranean Sea, based on samples from eight and seven areas, for blackbelly rosefish and European hake, respectively. Shape analysis was obtained through Wavelet analysis. Canonical analysis of principal coordinates provided significant evidence for different population units with a clear separation between the Atlantic and Mediterranean populations for both species. However, random forest procedures indicated that the discrimination power varied with species and locations. For blackbelly rosefish, various Atlantic populations were more evident than for European hake. Overall, the usefulness of otolith shape to delineate stock structure of two species with distinct life history traits across a broad spatial region from the mid-Atlantic isles to the polar region, as well as the Mediterranean was demonstrated. Moving forward, it will be key to align our growing understanding of population structure with our increasing knowledge on species' biological traits to ensure management units reflect population structure. [Display omitted] • Helicolenus dactylopterus and Merluccius are fishery exploited species. • We used otolith shape to define their stock structure in the Atlantic and Mediterranean. • Wavelet analysis and canonical analysis of principal coordinates revealed diverse population units. • Random forests showed that the discrimination power varied with species and locations. • Results suggest a higher degree of connectivity of M. merluccius in the Atlantic. [ABSTRACT FROM AUTHOR]

Blackbelly rosefish Helicolenus dactylopterus is a zygoparous fish whose males are equipped with the copulating organ named urogenital papilla (UP). This study deals with the morphology and the glycoconjugate pattern of the UP epidermis, which is the male tissue interacting with the female internal body during copulation. The carbohydrate content was studied by means of conventional and lectin histochemistry. The epidermis was shown to be a stratified cuboidal epithelium and to exhibit characteristic intraepithelial pits in the apical zone. The mucous cells are scattered in the epidermis. The epidermal cell layers and their thickness as well as the size of mucous cells varied along the UP. Conventional histochemistry showed that the mucous cells contained i) only neutral glycoproteins in the basal zone; ii) both neutral and acidic non-sulphated glycans as well as only acidic non-sulphated or sulphated glycoconjugates in the intermediate zone; iii) neutral and sulphated glycoconjugates in the apical zone. The mucous cells in the basal region expressed O-linked (mucin type) glycans terminating with αGalNAc, Galβ1,3GalNAc which could be α2,3-linked to sialic acid, and high mannose type N-linked glycans terminating with fucose, lactosamine, and sialic α2,6-linked to galactose/N-acetylgalactosamine; terminal Gal and terminal/internal GlcNAc were also found. The mucous cells in the intermediate zone lacked Galβ1,3GalNAc and showed less terminal α2,3-linked sialic acid, lactosamine, fucose, galactose, and internal N-acetylglucosamine residues. In the apical region, mucous cells only exhibited O-glycans terminating with GalNAc and N-acetylglucosamine. The demonstrated region-specific differences in the UP skin provide new insights into the reproductive biology of fishes with internal fertilization. [ABSTRACT FROM AUTHOR]

Two hundred and seven individuals (103 females and 104 males) of bluemouth Helicolenus dactylopterus (Scorpaeniformes, Sebastidae), a commercially important deep-water species with an unusual reproductive strategy, from the eastern Atlantic Ocean ranging from 13·9 to 37·5 cm total length ( LT) were analysed from September 2011 to October 2012. The analysis included gonad maturity phases and blood-plasma levels of oestradiol-17β ( E2), 11-ketotestosterone (11- KT) and 17,20β-dihydroxypregn-4-en-3-one (17,20β-P). Results confirmed the existence of an annual reproductive cycle with asynchrony between females and males and a spawning season from January to May. A pronounced peak in 17,20β-P in October for both sexes was associated with possible mating behaviour and recent copula. Levels of E2 increased preceding the elevation of the gonado-somatic index during ovarian growth and were lower during regression and regeneration. The frequency distribution of oocyte-embryonic stages and variation of hormone levels suggest the existence of daily rhythms. Fertilization was detected between 2000-0000 and 0800-1200 h and spawning took place throughout the day peaking between 2000 and 0000 h. The cyclic pattern of sex steroids and ovarian recruitment provides a new insight into the reproductive strategy of this species. [ABSTRACT FROM AUTHOR]

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Concentrations of V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Cd and Pb were determined in muscle, liver and gonads of two ecologically contrasting fishes, Helicolenus dactylopterus (benthic) and Pagellus bogaraveo (benthopelagic). Elevated concentrations of As, Se and Cd found in tissues of both species appear to mirror the contribution of volcanic activity to the natural inputs of elements to Azorean waters. Results showed different element accumulation between the two species. Whereas higher concentrations were found in the liver of P. bogaraveo , elevated values were observed in the muscle of H. dactylopterus . Differences in accumulation are most likely related to metabolic rates, diet specificities and habitat. Concentrations in gonads varied up to four orders of magnitude, being higher and more variable in P. bogaraveo than H. dactylopterus . Elevated values of Cd were detected in gonads of both species despite its non-essential role on metabolic functions, presumably related to elimination. [ABSTRACT FROM AUTHOR]

The behaviour of the scorpionfish Helicolenus dactylopterus and Pontinus kuhlii towards the zooplanktivores Anthias anthias and Callanthias ruber are described from rare in situ remote-operated vehicle (ROV) observations. The events were recorded by ROV SP on gorgonian habitats of Dentomuricea meteor and Viminella flagellum, at the summit of Condor seamount (212-223 m; Azores, Northeast Atlantic). Behaviour in both species included approaching the zooplanktivores from a sitting position, orientating the snout in front of the object and swimming in a straight line. After an initial slow displacement, it follows an adduction of dorsal, pectoral and anal fins and an increase in speed, occasionally accompanied of a burst swim. H. dactylopterus can reach up to 0.8 m above the seafloor, departing from more than 1.5m distance; P. kuhlii was observed only on one occasion, chasing A. anthias from 0.64-m distance, with average swimming velocities of 1-2 m/s. The possibility of predatory or agonistic behaviour is discussed, with more evidence being gathered towards the former, representing a possible linkage between the pelagic and the benthic realm. [ABSTRACT FROM AUTHOR]

Highlights: [•] A portion 160g of fish contributes to the RDA/RDI of essential elements. [•] 49% and 84% of n-3 PUFA RDI achieved with 160g of A. carbo and L. whiffiagonis. [•] Cd and Pb contents in all fish muscle samples were below the EU limit. [•] Consumption of liver from studied fish species must be avoided. [Copyright &y& Elsevier]

Abstract: Deep sea rockfish, Helicolenus dactylopterus and Pontinus kuhlii from the Azores archipelago were used to study population structuring using the trace element composition of the otolith. Through solution-based inductively coupled plasma mass spectrometry we identified elemental profiles that adequately identified fish from different island groups in the region (East, West and Central). Mg:Ca, Pb:Ca and Li:Ca ratios combined to distinguish H. dactylopterus with 67% overall success. Sr:Ca, Ba:Ca, Li:Ca and Cu:Ca provided adequate distinction in P. kuhlii with a mean jack-knifed classification success of 75%. This was a first attempt at determining the distinguishability of fish aggregations from this oceanic island setting, where suitable habitat for these species is limited and fragmented. Results of our study corroborate with previous research pointing to constrained home ranges for these species. Implications for fisheries management are important since these commercial resources should be managed locally rather than regionally. [Copyright &y& Elsevier]

Highlights: [•] Sectioned and whole otoliths are compared using the same bluemouth individuals. [•] Bias and precision are analyzed. [•] The results indicate that both methods can be used for aging bluemouth. [ABSTRACT FROM AUTHOR]

Mercury (Hg), cadmium (Cd), and lead (Pb) were quantified in muscle tissue of 5 species of demersal fish (european conger eel, rosefish, brown ray, blackbellied angler, and red mullet) commonly consumed in Italy. In all species studied, Hg was the most abundant element, followed by Pb and Cd, which exhibited comparable levels. Cd and Pb concentrations did not differ either within individuals of the same species or among various species examined, whereas Hg accumulation was species-specific. Significant positive correlations between Hg concentrations and fish length for the 5 characterized species were observed. From a public health standpoint, Pb concentrations were under the legal limit for human consumption indicated by European Regulation, whereas Hg and Cd content occurred at levels exceeding the respective critical values in most of the samples examined. The estimated weekly intakes (EWIs) as well as the target hazard quotients (THQs) for Cd and Pb indicated that fish were safe for human consumption, whereas major concern was related to Hg. Fish size-related changes in Hg concentrations determined high THQ and EWI values relatively to larger size fish consumption of these species, except for red mullet, suggesting potential health human risk. A continuous surveillance system of Hg content in fishery products, especially in certain species that for physiological reasons concentrate Hg more easily than others is crucial for consumer health protection. Practical Application: The present article deals with metal (Hg, Cd, and Pb) concentrations in commercially important demersal fish from Mediterranean Sea. The dietary intakes of these elements have been estimated and the dietary exposure assessment was calculated. This kind of study will help the consumers to make an informative choice when buying fish. [ABSTRACT FROM AUTHOR]

Abstract: The age, growth and reproductive biology of bluemouth, Helicolenus dactylopterus were studied in order to assess the use of these life history parameters as possible population discriminators in Portuguese waters. Fish were obtained from commercial landings in mainland Portugal (Peniche), Azores, and Madeira and supplementary samples were obtained from research surveys in the Portuguese continental slope. Significant differences in mean total-length and mean length-at-age were found between the three areas. The reproductive biology was analysed using the annual sexual cycle, three bionergetic indexes and the maturity ogives. Individuals presented a similar reproductive strategy in Portuguese waters with asynchrony of sexual cycles, similar female spawning season in the three areas and a sperm retention period in the ovaries of 1 to 6–7 months. The bionergetic indexes showed significant differences through the maturative stages and among areas. No significant differences were obtained when comparing the length at first maturity between mainland Portugal and Azores for both sexes. The results of this study will provide a comprehensive understanding of this species life history and presented useful evidence that can support the presence of different populations in the Portuguese waters. [Copyright &y& Elsevier]

In order to investigate the feeding habits of Helicolenus dactylopterus dactylopterus along the continental Portuguese coast, a total of 619 individuals were sampled of which 60% contained food in their stomach and 35% had more than one prey item. Among the 81 prey items that were identified in the stomachs, benthic and benthopelagic prey prevail on this species diet. Acantephyra sp, Pasiphaea sp, mysidacea, and teleostei n.i. were the prey with the higher percent index of relative importance (%IRI) value. Three length groups (5-20 cm, 21-27 cm, and 28-48 cm) were defined through cluster analysis of the mean abundance of prey items. A permutational MANOVA detected significant differences in the diet and stomach fullness index for TLG, season, and maturation stage. Smaller fishes had a generalized diet, feeding mainly on mysidacea changing their diet above 20 cm TL, where a major consumption of natantia was found. The larger individuals, >28 cm TL, present a less generalized diet with pisces as dominant prey group. Seasonally, natantia and pisces were the principal prey groups during spring and winter, respectively, while mysidacea and other crustaceans were predominant during the rest of the year. Mysidacea were also the main prey group for immature individuals while natantia and pisces were the principal prey groups to the other maturity stages. The results of this study indicate that H. d. dactylopterus has a diverse diet focused on small crustaceans such as misyds and as specimens grow shrimps and fishes become more consumed, with larger specimens having a more specialized diet. The different nutritional needs during spawning season also seemed to influence the feeding habits of H. d. dactylopterus. [ABSTRACT FROM AUTHOR]

The present paper shows the multidisciplinary approach used to assess the eco-toxicity of chemical munitions lying on the seabed in the Southern Adriatic Sea where aerial bombs charged with mustard agent and organoarsenlc chemical war-fare agents (CWAs) have been dumped. Sampling activities and laboratory analyses have been carried out on two sen-tinel species, the blackbelly rosefish, Helicolenus dactylopterus, and the European conger, Conger conger, collected in a CWA dumping site 35 nm from the coast of Apulia, Italy, and from a reference site. Fish were analyzed through an ecotoxicolo-gical approach, integrating chemical analysis and biological responses. Degradation products of the blister agents ö/s-(2-chloroethyl)sulphide, com-monly known as mustard agent or yperite (also called sulfur or sulfur mustard), were found in sediment samples collected nearby aerial bombs. Although no evi-dence of these compounds was detected in tissues of either fish, levels of heavy metals (arsenic and mercury), potentially released by rusted chemical weapons, were significantly higher in sediment and fish from the CWA site compared to the reference site. Severe external and internal lesions were observed in fish captured in the CWA site, with congers displaying small to large skin ulcers along the body. Health assessment index (HAI) values, as well as spleen melano-macrophages cen-tres and CYP1A ethoxyresorufin-Odeethylase activity were higher in fish from the CWA site, indicating a chronic state of illness and environment degradation. The working procedures and analyses performed during these surveys could be suitable for future biomonitoring studies in other CWA dumping sites. [ABSTRACT FROM AUTHOR]

Summary Differences in size selectivity of commercial (40 mm diamond mesh, 40D), larger mesh (48 mm diamond mesh, 48D), and square mesh codends (40 mm square mesh, 40S) for hake ( Merluccius merluccius), greater forkbeard ( Phycis blennoides), blackbelly rosefish ( Helicolenus dactylopterus dactylopterus) and four-spot megrim ( Lepidorhombus boscii) were investigated in the Aegean Sea. The study was conducted using the covered codend method. Data were analysed taking between-haul variations into account. Results showed that changing from a 40D to 48D codend significantly improved mean L50 values, with increases of about 22% for hake, 8% for greater forkbeard, 20% for blackbelly rosefish, and 11% for four-spot megrim (P = 0.000). A change from diamond to square mesh configuration with the same 40 mm netting also significantly increased the mean L50 values, with 45% for hake, 36% for greater forkbeard, and 25% for blackbelly rosefish (P = 0.000). For four-spot megrim the mean L50 value was about 10% lower, but this difference was statistically insignificant (P > 0.05). Despite the increases in L50 values, this study concludes that the selectivity of the 48D and 40S codends is still not sufficient to release fish smaller than length at first maturity for these four species. [ABSTRACT FROM AUTHOR]

The bluemouth, Helicolenus dactylopterus, is a deep-sea scorpionfish widely distributed in the Atlantic Ocean and the Mediterranean. It is a common by-catch associated to many demersal fisheries. However, there is little information about the stock structure, stock dynamics and life history parameters of the bluemouth. From the perspective of stock identification, it is important to study growth in fish populations to better understand the possible morphological differences among populations and when and why do they arise. Thus, the aim of this study was to determine the growth (allometric) trajectories of shape for several bluemouth populations in Northeast Atlantic and Mediterranean using landmark-based geometric morphometric techniques. In this study, ontogenetic allometry was present in all of the bluemouth samples. Ontogenetic shape changes were most evident in the head and pectoral area, affecting the position of the snout, preopercular spines and pectoral fins, but changes in body depth and length were also important. However, the degree to which these ontogenetic shape changes were present in bluemouth from each of the studied areas was different, indicating that their growth trajectories are not homogeneous. The importance of this finding for size-correction of the shape variables in morphometric studies for stock identification is also discussed. [ABSTRACT FROM AUTHOR]

In this study, landmark-based geometric morphometric methods were applied to evaluate the possible existence of different bluemouth, Helicolenus dactylopterus (Delaroche, 1809), populations in the NE Atlantic. Fish were obtained from commercial landings in Azores, Madeira, and Peniche (mainland Portugal). Samples from a research survey along the Galician coast (Spain) were also included in this study. A generalized procrustes analysis was done to remove non-shape variation. Then, the obtained shape variables were statistically adjusted to eliminate allometry and permit a comparative analysis of the samples. The discriminant analysis performed to test the homogeneity of the data set regarding sex revealed no shape differences between males and females within the four areas under study. The body shapes of bluemouth differed significantly among the four areas using Procrustes distances ( P < 0.01). In this study, a considerable morphological heterogeneity within the Azores group was observed, which could reflect a substructure of the bluemouth population within this area. According to our results, bluemouth from Galicia and Peniche seem to be relatively well separated from each other, despite both areas are relatively close geographically. Bluemouth from Madeira was well differentiated from the rest of locations and presented the highest correct classification rate in the discriminant analysis. In conclusion, morphological differences suggest that different bluemouth populations exist in the NE Atlantic, but an integrated approach, using different methods, would be needed to confirm the population structure of this species. [ABSTRACT FROM AUTHOR]

The bluemouth, Helicolenus dactylopterus dactylopterus (Pisces: Sebastidae), is a zygoparous species with internal fertilization that stores the spermatozoa in crypts within the female ovaries. It spawns gelatinous egg masses that were investigated in this study. Histological analysis confirmed that the ovarian wall and peduncular epithelia play an important role in the production of this gelatinous matrix that contained both oocytes and embryos. Cleavage and blastulae were the most frequent embryonic development stages observed and the tail bud was the latest stage reached. The chemical composition of the matrix was also investigated, revealing that water and proteins are the major components of this substance. This is the first study exclusively dedicated to the investigation of the composition, function and importance of the gelatinous matrix of H. d. dactylopterus in the context of its reproductive strategy. [ABSTRACT FROM AUTHOR]

The bluemouth Helicolenus dactylopterus dactylopterus is a zygoparous species that spawns multiple batches of embryos enclosed within a gelatinous matrix. Oocyte development is asynchronous, and the recruitment of secondary growth oocytes occurs continuously during the developing phase, but stops before the start of the first spawning ( i.e. fecundity is determinate). The number of developing oocytes can be estimated as a function of the total length of the fish, its ovary mass and its gonado-somatic index. Only at the onset of spawning, when potential fecundity is determined, does condition also have a significant effect. The low levels of atresia detected during most of the spawning season show that this mechanism does not substantially affect the process. There is variability both in the spawning interval (with a mean of 2 days) and in the number of embryos comprising every single batch (up to 37 000). Expected effect of fisheries on the reproductive traits of this deep-sea species is also discussed. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, the macroparasite assemblage infecting Helicolenus dactylopterus (Delaroche, 1809) in three different areas off the Portuguese coast was evaluated in order to assess their use as biological tags in stock identification. Fish were obtained from commercial landings in Azores, Madeira and mainland Portugal (Peniche), and were examined for macroparasites infections according to standard procedures. Parasite assemblage composition and the prevalence and mean abundance of each macroparasite taxa within each area were calculated. Amongst the 20 taxa found, 13 were selected as good biological tags, presenting statistically different infection levels between areas. Anisakidae larvae, which presented different prevalence and mean abundance levels between the three areas, were further identified according to the restriction fragment length polymorphism (RFLP) pattern on TaqI, HinfI and HhaI. The multivariate discriminant analysis applied to the macroparasites species present in more than one area and showing prevalence higher than 10% revealed a high differentiation among the three sampled areas suggesting at least three different bluemouth stocks in Portuguese waters. [Copyright &y& Elsevier]

Currently, traditional Mediterranean trawls are generally made with non-selective netting and the fishing boats are involved in multi-species fisheries. As a result, most near-shore stocks are over-exploited. Weather permitting, the demersal trawl fleet tends to fish in relatively deeper, international waters of the Aegean Sea, where the catch is usually higher. Therefore, the need for evaluation of the codends used in this fishery and the potential improvements to their selectivity are of prime importance. In the present study, selectivity data were collected for hake ( Merluccius merluccius), blue whiting ( Micromesistius poutassou), greater forkbeard ( Phycis blennoides), blackbelly rosefish ( Helicolenus dactylopterus dactylopterus) and fourspotted megrim ( Lepidorhombus boscii) in commercial (300 MC) and square mesh top panel (SMTPC) codends. Trawling was carried out at depths of 274–426 m onboard a commercial vessel chartered for a 15-day sea trial in August 2004. Selection parameters were obtained by fitting a logistic equation using a maximum likelihood method. Results of the selectivity analysis indicated that the commercially used 40 mm nominal mesh size PE codend was rather unselective for the species investigated in this study. In general, the square mesh top panel codend has relatively higher L50 values than the commercial codend. However, except for blue whiting, even this codend is rather unselective when 50% maturity lengths (LM50) are considered. [ABSTRACT FROM AUTHOR]

The blue-mouth, Helicolenus dactylopterus dactylopterus (Delaroche, 1809) (Pisces: Scorpaenidae), is a scorpionfish widespread in the whole Mediterranean basin, where it plays an important ecological role in deep-sea fish communities. The depauperation of this large-size sedentary and slow-growing fish can be an index of overexploitation. This species is found throughout all Italian seas; the juveniles are mainly located around 150–300 m depth, whereas the adult specimens are spread over a wider depth range from 200 m to as deep as 1000 m. The abundance in number and weight, the spatial distribution, the population structure, the growth and the recruitment pattern of H. dactylopterus were analysed in this study. The present paper integrates data from 11 bottom trawl surveys carried out in the Southern Tyrrhenian Sea (Central Mediterranean) along Calabrian and Sicilian coasts, within the framework of the MEDITS Project. A total of 1412 specimens of H. dactylopterus weighting 20.051 kg were caught. The species appeared in 40% of the 296 hauls analysed, throughout the whole depth range surveyed. The highest values of frequency of occurrence (>67%) were obtained in the slope, whereas in the shelf they fell to around 16%. On the continental shelf the species was found between 106 and 196 m depth, and in the slope between 400 and 645 m. The highest mean density index (N·km−2) value was obtained in the 100–200 m depth stratum, whereas the highest mean biomass index (kg·km−2) value was recorded in the deeper 200–500 m stratum. The length distribution of the specimens ranged between 2.5 and 24.5 cm. From the Von Bertalanffy growth model the following parameters for the whole population were obtained: L ∞: 30 cm; K: 0.16 year−1; t0: −0.02. The sampled population is composed mainly of the young-of-the-year fraction, which can reach up to 98% of the whole catch. Recruits (age 0+) and juveniles (age up 4 years) are limited to waters shallower than 500 m, whereas adults are present below this depth. [ABSTRACT FROM AUTHOR]

Sequeira, V., Neves, A., Vieira, A. R., Figueiredo, I., and Gordo, L. S. 2009. Age and growth of bluemouth, Helicolenus dactylopterus, from the Portuguese continental slope. – ICES Journal of Marine Science, 66: 524–531. In all, 933 bluemouth (Helicolenus dactylopterus) were obtained from bottom-trawl research surveys along the Portuguese continental slope between October 2005 and February 2007 and from commercial landings. Age was determined by reading whole sagittal otoliths, and age estimates were validated by daily growth increment (DGI) analysis. Fish ranged from 5.2 to 44.9 cm, which corresponded to fish between 0 and 30 years old. The mean total length obtained from DGI analysis for age class 1 fish was 8.6 cm, corresponding to otoliths with a mean radius of 1.8 mm. As no statistical differences between sex were observed, the von Bertalanffy growth equation fitted was Lt = 45.50[1 − e−0.05(t+4.01)]. Comparisons with other studies using Hotelling's T2 test and the growth perform index (Ф) are drawn. The growth rates estimated in this study using whole otolith readings were the lowest of all the studies available, and the estimated L∞ is lower then those obtained for Azorean waters and higher than those published for the Mediterranean. [ABSTRACT FROM PUBLISHER]

Good knowledge of the spatial distribution of fish is critical to stock assessment and successful fisheries management. Depth is often the main gradient along which faunal changes occur when analyzing shelf and upper slope assemblages, and thus knowledge of the bathymetric distribution of fish species is of great importance. The depth distribution of 16 fish species ( Chelidonichthys lucernus, Helicolenus dactylopterus, Hoplostethus mediterraneus, Lepidorhombus boscii, Lophius budegassa, Merlangius merlangus, Merluccius merluccius, Micromesistius poutassou, Mullus barbatus, Mullus surmuletus, Pagellus erythrinus, Peristedion cataphractum, Phycis blennoides, Serranus cabrilla, Trigla lyra, and Trisopterus minutus) of the Aegean and the Ionian Seas was evaluated by analyzing experimental bottom trawl data, using generalized additive modeling (GAM) techniques. A variety of bathymetric distribution patterns was observed. The main bathymetric zone of each species was defined based on the modeled relative density. Specifically, the lower and upper limits of the main bathymetric zone of each species were defined as the depths where the estimated relative density of the species becomes less than 1% of the maximum. This definition is proposed as a better and more informative alternative than reporting the minimum and maximum depths of encounter. [ABSTRACT FROM AUTHOR]

Abstract: The objectives of this work were to monitor the spatial distribution of Helicolenus dactylopterus and to determine if the species density of the population off the southern Portuguese coast was declining. The data were collected during four summer research surveys. For the surveys in 1997 and 1998 we used a random stratified design, whereas in 2000 and 2001 we conducted surveys using a regular grid. All surveys were conducted on board the RV “Noruega”. We used the kriging estimator to compute density estimates of H. dactylopterus in the survey area. In a first approach, we determined a spatial structure for each year, but directional semi-variograms could not be computed due to the scarce number of points. Thus, herein we present a new approach to finding the spatial structure when data are scarce but repeated in time. With this approach, data for various years are assumed to be realizations of similar processes; this assumption allows directional semi-variograms within sectors with the same topography to be computed. The kriging density estimates obtained assuming isotropy and the ones obtained assuming anisotropy were very similar, for the set of data analysed here, but in the second case a greater detail can be achieved. Our data show that the density estimates decreased by more than 50% from 1995 to 2000 and that the population began to recuperate from 2000 to 2002. [Copyright &y& Elsevier]

The aim of this work was to analyse the ultrastructure of storage crypts and stored spermatozoa, and to describe changes during the annual reproductive cycle of the bluemouth Helicolenus dactylopterus dactylopterus, which has internal fertilization and a zygoparous mode of reproduction. Spermatozoa had elongated heads and long midpieces, two characteristics which are thought to be fairly advanced and correlated with internal fertilization, as is the case of the bluemouth. A remarkable spermatozoon feature was the retention of a significant quantity of cytoplasm around the head, a condition that appeared to be related to nourishment during the long storage period, up to 10 months in the intraovarian crystal structures of the female. Male sex cells’ protection against the female immune system was ensured by junctional complexes between the crypt cells composed of tight junctions and desmosomes. [ABSTRACT FROM AUTHOR]

Recent trends in the abundance, distribution and growth of bluemouth in Scottish waters are described. The observations are all based on an ecologically important time-series database of trawl surveys conducted annually between 1925 and 2004 by Fisheries Research Services, Aberdeen. We examine the period 1985–2004 in detail. Bluemouth abundance has increased over the last decade both along the continental shelf west of Scotland and in the North Sea. In 1991 bluemouth appeared in the northern North Sea as a distinct cohort, with total lengths ranging between 6 and 8 cm. 1991 was a year of exceptional Atlantic inflow into the North Sea, and it is likely that the bluemouth used this water mass as a highway, entering from the north and west as small individuals. The fish from 1991 grew steadily and formed a distinct length mode that we track here until its disappearance in 2002. In the first few years following this influx, bluemouth were recorded all around the northern North Sea, but since 1997 numbers have declined and its distribution has shrunk into one of two International Council for the Exploration of the Sea (ICES) statistical rectangles (39F1 and 40F2) which are positioned in the central part of the North Sea. Since 1991 only one subsequent and relatively minor immigration of bluemouth into the North Sea has taken place, in 1998. The composition of the North Sea bluemouth population as a single cohort allows its spatial distribution, expansion and growth rate to be charted, discussed and described. [ABSTRACT FROM AUTHOR]

Abstract: The Mediterranean population of bluemouth, Helicolenus dactylopterus dactylopterus (Pisces: Scorpaenidae), is analysed based on 1253 bottom trawls carried out during spring research cruises (MEDITS) along the Iberian Mediterranean coast, from 1994 to 2004. Most individuals were caught at depths of between 201 and 500m. Both sexes were equally represented at a mesoscale in the entire study area and males attained a larger size than females. A latitudinal and bathymetrical distribution of the bluemouth population, previously observed by some authors, was confirmed. From the south Mediterranean to the north, clear decreases in density, mean total length, biomass value, density indexes and recruitment percentages were observed. The inter-annual oscillation in density indexes and biomass was also estimated. After analysing the structure of the population along the entire western coast, a possible northward dispersal movement of young specimens from the Alboran Sea is discussed to explain why, despite the fishing pressure in the northern sector, the biomass value remains relatively stable. [Copyright &y& Elsevier]

Abstract: The age and growth of the Helicolenus dactylopterus (Delaroche, 1809) in the Azorean waters were studied using whole and sliced otolith readings. Individuals were collected during demersal surveys carried out around the Azores islands and its most important fishing banks and also from commercial landings. A total of 1024 individuals were measured, weighed and their sex was determined. Individuals ranged from 3 to 49cm total length (TL) and their estimated ages between 0 and 32 years old. The otoliths showed the typical teleost fish pattern with alternated opaque and hyaline rings. Significant differences between sliced and whole otolith readings were found, especially after 7 years old (>25cm TL). Sliced otoliths were found easier to read, regardless of TL or age. Comparisons with other studies for the Azores region and other areas are discussed. [Copyright &y& Elsevier]

Helicolenus dactylopterus and Merluccius merluccius are widely distributed on the continental slopes of the Atlantic and Mediterranean and have quite different life histories. Both are commercially exploited, but little is known about their stock structure. Fish otolith composition is thought to reflect both endogenous processes and external factors, some of which relate to the surrounding environment, and therefore may be used as a tool for stock discrimination. The elemental composition of sagittal otoliths was examined using both solution-based inductively coupled plasma mass spectrometry of the whole otolith and laser-ablation analysis of the otolith nucleus. The relative concentrations of strontium, barium, and copper in dissolved whole otoliths contributed to the discrimination between H. dactylopterus samples from different geographic areas. Surface analysis of the otolith nucleus did not allow separation of geographic groups. For M. merluccius, separate analyses of the whole otolith data for the Atlantic and Mediterranean samples gave a clear distinction of the different groups within each ocean basin. Analysis of the M. merluccius nucleus composition indicated some differences in elemental concentration among both Atlantic and Mediterranean samples. Magnesium and lead were important elements in separating the groups in the Atlantic, and barium, strontium, and lead were important in the Mediterranean. [Copyright &y& Elsevier]

Sagittal otoliths of Coryphaenoides rupestris(roundnose grenadier), Helicolenus dactylopterus(bluemouth) and Merluccius merluccius(European hake) were collected using a variety of handling and storage treatments and their elemental composition was examined using inductively coupled plasma mass spectrometry. Some differences between element concentrations were identified between the control and treatment groups, most notably for the element Li. For H. dactylopterus and M. merluccius, Li concentrations were significantly higher in the otoliths extracted with metal forceps and stored in paper envelopes (treatment), compared to those from the same fishes that had been extracted using plastic forceps and stored in polyethylene vials (control). Lower concentrations of Ba and Cr were found in M. merluccius otoliths extracted from fish that had been stored frozen. The presence or absence of elemental concentrations above the instrumental limits of detection was noted, but no significant differences were identified between otolith pairs for any of the treatments. The differences between otolith pairs attributable to storage and handling effects are small compared to between-area differences. [ABSTRACT FROM AUTHOR]

Helicolenus dactylopterusis an Atlantic benthopelagic fish species inhabiting high-energy habitats on continental slopes, seamounts and islands. Partial sequences of the mitochondrial control region (D-loop) and cytochromeb(cytb) were used to test the hypothesis thatH. dactylopterusdisperses between continental margin, island and seamount habitats on intraregional, regional and oceanic scales in the North Atlantic. Individuals were collected from five different geographical areas: Azores, Madeira, Portugal (Peniche), Cape Verde and the northwest Atlantic. D-loop (415 bp) and cytb(423 bp) regions were partially sequenced for 208 and 212 individuals, respectively. Analysis of variation among mitochondrial DNA sequences based on pairwiseF-statistics andamovademonstrated marked genetic differentiation between populations in different geographical regions specifically the Mid-Atlantic Ridge (Azores)/northeast Atlantic (Portugal, Madeira) compared to populations around the Cape Verde Islands and in the northwest Atlantic. Some evidence of intraregional genetic differentiation between populations was found. Minimum-spanning network analysis revealed star-shaped patterns suggesting that populations had undergone expansion following bottlenecks and/or they have been colonized by jump dispersal events across large geographical distances along pathways of major ocean currents. Mismatch distribution analysis indicated that Azores and northwest Atlantic populations fitted a model of historical population expansion following a bottleneck/founder event estimated to be between 0.64 and 1.2 million years ago (Ma). [ABSTRACT FROM AUTHOR]

The reproductive patterns of Helicolenus dactylopterus are presented; the species is zygoparous. The first photographic record of three embryonic stages in the intraovarian gelatinous matrix is also presented. [ABSTRACT FROM AUTHOR]

The ultrastructure of ovarian sperm storage of Helicolenus dactylopterus dactylopterus is described, before and after the spawning period. The spermatozoa remain inside cryptal structures that are situated in the interlamellar gaps and are connected to the ovarian lumen by a duct. This complex forms a highly specialised structure. During the long storage period, crypts are richly vascularised. Their surrounding simple epithelia have intercellular junctions that may serve to protect the spermatozoa from the female immune system. At the moment during which insemination of mature oocytes occurs, the sperm may be expelled from cryptal structures by means of a spasmodic contraction. During the post spawning period, residual spermatozoa that remain in the crypts are eliminated by cryptal phagocytes. At the end of the process the crypts contain only an amorphous material. [ABSTRACT FROM AUTHOR]

This paper presents data on the age, growth, maturity, and distribution of Helicolenus d. dactylopterus (Delaroche 1809) from the Rockall Trough area. The results are based on a series of deep-water trawl surveys carried out on the continental slope west of Ireland and Scotland between 1992 and 1993. Ages ranged from 1 to 43 years for males and 1 to 37 years for females with most fish aged between 3–14 years. The species was found to be sexually dimorphic with males attaining a greater length and weight (L∞=37.2 cm; W∞=747 g) than females (L∞=31.0 cm; W∞=700 g). Age and growth estimates were determined for both sexes and the Brody growth coefficient for both sexes indicate that this species is relatively slow growing (male K=0.06; female K=0.09). Ripe female fish were only found in April and May in a specific area. Using total lengths 50% of male fish were mature at 26 cm (ages 15–16) while 50% of female fish were mature at 23 cm (age 13). Catch data were sporadic but the largest catches were obtained on the southern slope of the Rockall Trough in April at a depth of 650–950 m. The fish from this area had a much greater range of sizes than fish from the eastern slopes of the Rockall Trough. [ABSTRACT FROM PUBLISHER]

Blue-mouth (Helicolenus dactylopterus) is one of four species of the Scorpaenidae which may be caught in the North Sea. It is known as a typical deep water fish which lives along the shelf edge. Reports from the North Sea have been rare. An invasion of blue-mouth in the northern North Sea that took place in the winter 1990/91 is described. Blue-mouth have spread over a considerable area since and, recently, catches were even reported from the southern North Sea. Length distributions are given as well as age/length information from fish collected in the North Sea and at Rockall. [ABSTRACT FROM PUBLISHER]