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The deep sea fishery targeting the black and intermediate scabbardfishes (Aphanopus spp.) off the Madeira archipelago represents one of the world long standing exploitations of meso- and bathypelagic fishes. The intensive fishing of the target species caused an overall decrease of more than (51%) in their yields. Fishing vessels had to go further away of the usual fishing grounds, leading to a progressive geographical expansion of the fishery reaching as far as the Southern Azores Seamount Chain and the Canaries Economic Exclusive Zone. Changes in the fishing pattern of the Madeira fleet were also registered along the last decades. Trends of the spatial distribution of the fishing sets and of the fishing pattern exerted by the Madeira fishing fleet in the North-central eastern Atlantic are presented herein and its implications for the conservation of the resource and fishery management are discussed, along with the emergence of new fisheries upon this resource at regional level. Changes in the conservation and management strategies followed so far is urgent and should integrate all fisheries acting upon the resource and take in account the phase of the life cycle it fishes otherwise the sustainability of the exploitation may soon be in danger. Authors propose a prohibition of bottom trawling bellow 200 m deep and a temporary closure of the fishery in some areas.

The influence of different culinary practices (boiling, frying, grilling) and seasoning (salt, lemon, combined) on the Hg levels (total and organic) found in three marine fish species (Scomber scombrus, Dicentrarchus labrax, Aphanopus carbo) was evaluated. Cooking affected the Hg levels in a species-dependent manner. With the exception of D. labrax, T-Hg decreased in grilling and frying, while O-Hg decreased in all culinary practices. For all species, some Hg was also found in the boiling water. Since O-Hg is the major portion of Hg in fish muscle and all culinary practices removed O-Hg, setting consumption thresholds in terms of T-Hg in raw tissue seems protective and adequate. S. scombrus and D. labrax emerge as healthier and safer choices, while moderate consumption of A. carbo is recommended. These findings reinforce the need to maintain FAO/WHO's recommendation that vulnerable groups should eat less than 100 g of predatory species per week.

Scabbardfishes are a group of deep-water fishes from the family Trichiuridae that form the basis of an important longline fishery in the Madeira archipelago, in the southern part of the Northeast Atlantic. Two closely related and morphologically similar species occur in this area: the black scabbardfish, Aphanopus carbo, and the intermediate scabbardfish, A. intermedius. In this study, 112 scabbardfish specimens captured in Madeira, Canary Islands, and nearby seamounts were examined for the presence of anisakid nematodes. Infection levels were extremely high in both species. A generalised linear model was applied to anisakid abundance, using fishing location and several host parameters as predictors. Fish length had a strong positive effect, and A. carbo was more heavily infected than A. intermedius, whereas fishing location had no effect. The microhabitat distribution of anisakid larvae within the fish followed a gradient from the stomach to other visceral organs; however, infection levels in the muscle were not negligible, which raises safety issues for consumers. It is strongly recommended that scabbardfish should never be eaten raw or undercooked, unless frozen prior to consumption.

Novel statistical tools were tested with the muscle and liver of anglerfish species ( Lophius piscatorius and Lophius budegassa ) and black scabbard fish ( Aphanopus carbo ) and the muscle of blackbelly rosefish ( Helicolenus dactylopterus ) and megrim species ( Lepidorhombus boscii and Lepidorhombus whiffiagonis ). Methylmercury (methyl-Hg) content and selenium (Se) and eicosapentaenoic (EPA) + docosahexaenoic acids (DHA) were analysed. For muscle, it was determined that probabilities of the methyl-Hg intakes exceeding the provisional tolerable weekly intake (PTWI) (weekly meal, from 1:12 in L. boscii to 1:2 in H. dactylopterus ) were always higher than probabilities of the Se and EPA + DHA intakes surpassing the recommended daily allowance (RDA) (weekly meal, never surpassing 1:2,938,713 in L. budegassa ) and intake (weekly meal, never surpassing 1:13,974 in L. whiffiagonis ), respectively. For liver, probabilities of the Se intakes exceeding the RDA (weekly meal, from 1:82 in L. piscatorius to 1:1.2 in A. carbo ) were higher than probabilities of the methyl-Hg intakes exceeding the PTWI (weekly meal, from 1:96 in L. budegassa to 1:4 in A. carbo ). The Se health benefit values calculated for the muscle (from 5.5 in H. dactylopterus to 27.5 in L. budegassa ) and liver (from 165.7 in L. piscatorius to 1041.7 in A. carbo ) were all positive.

Fishing is occurring all over the globe, with an increase trend of exploiting deep stocks. Several species are currently targeted from the deep ocean, and some artisanal fisheries developed fishing gears, e.g. long lines, with limited impact to the environment but scarce information is available on biological aspects of these exploited stocks. In the Macaronesian region and specifically in Madeira archipelago, two Aphanopus sympatric species have been extensively exploited for decades but no detailed information is available on the spatial and vertical distribution of both species (Aphanopus carbo and Aphanopus intermedius). Currently, they represent an important percentage of landings from artisanal fishermen of Madeira (27% of the total catches in 2017). We herein observed that they showed a pattern of depth segregation, where adults of both species are more abundant (ca. 80%) at deeper seafloor (> 2500 m). A. intermedius was more numerous in fishing areas with greater seafloor depth (> 4500 m) compared to A. carbo. This pattern may be explained by a food source overlap between both species, and also the vertical segregation within the same species may be considered as a pattern to avoid cannibalism. Also, migration patterns were found in both species being more pronounced for A. intermedius where > 86% of individuals were collected offshore (> 12 n.m.). The present results constitute a step forward to start developing integrative management actions to preserve stocks of both species in the medium and long term in the study region.

The aim of this work was to evaluate the hazards and benefits of the consumption of 6 deep-water fish species from the Portuguese coast. Samples from muscle and liver of Lophius piscatorius and Lophius budegassa and Aphanopus carbo and from muscle of Helicolenus dactylopterus and Lepidorhombus boscii and Lepidorhombus whiffiagonis were analyzed. It was found that a portion size of 160 g significantly contributes to the recommended daily allowance/intake (RDA/RDI) for a balanced human diet, with respect to the essential elements analyzed. Moreover, 49% and 84% of the RDI of 500 mg for main n -3 polyunsaturated fatty acids was achieved through consumption of a 160 g portion of A. carbo and L. whiffiagonis , respectively. Average Cd and Pb contents in all fish muscle samples were consistently below the EU limit. Attending to the tolerable weekly intake/provisional tolerable weekly intake (TWI/PTWI), it appears that studied species muscle does not represent a hazard for human consumption. However, the consumption of liver of the studied fish species must be avoided. A weekly meal of L. whiffiagonis may be advised on the basis of its significant contribution for elemental and n -3 fatty acid requirements and its minimal contamination risks.

A risk–benefit assessment was performed in two marine resources of great importance in Southern Europe, i.e. black scabbard fish (Aphanopus carbo) and edible crab (Cancer pagurus), by determining the intake of Methyl-Hg, Cd, Se and EPA + DHA through the consumption of these species, as well as the associated probability of exceeding the tolerable weekly intakes (TWI; for Methyl-Hg and Cd) or dietary reference intakes (DRI; for Se and EPA + DHA). Average weekly intakes (AWI) were estimated by combination of the consumption frequencies in the Portuguese population and the concentration of each constituent. To estimate probabilities, two estimators were used: plug-in (PI) for higher probabilities and tail estimation (TE) based on the application of the extreme value theory to intakes distribution curves for lower probabilities. It was found that edible crab's white meat (meat from claws and legs) can be included on a well balanced diet, but black scabbard fish and edible crab's brown meat (mixture of gonads and hepatopancreas) should be consumed parsimoniously by adults and children.

The black scabbardfish is a deep water species of high commercial interest in the NE Atlantic. Specimens were collected from commercial trawls to the west of the British Isles and from longliners operating near Madeira between September 2008 and May 2010. Stomach content analysis was confined to samples from the northern area, because of a high number of empty stomachs from Madeira. Stable isotope analyses identified that black scabbardfish feeds on species with epipelagic and benthopelagic affinities. For the west of British Isles, the δN values were significantly different between seasons suggesting a change in the diet throughout the year. Black scabbardfish have higher δN and δC values compared with other co-occurring benthopelagic feeders and lower nitrogen values than the true benthic predators and/or scavengers. Comparison with stable isotope analysis in samples from Madeira indicated that black scabbardfish feed at a similar trophic level and has the same trophic niche width in both areas, assuming similar baseline isotope compositions. The diet in the northern area comprised fish (68% N), crustaceans (22% N) and cephalopods (15% N) with blue whiting ( Micromesistius poutassou ) constituting 40% of the prey. Seasonal shift in diet was observed, with a predominance of blue whiting (70%) in the first quarter of the year, shifting to a more diverse diet in the remainder of the year. These results indicate that the diet of black scabbardfish is closely linked with the seasonal migration of blue whiting and that they likely select prey in proportion to availability. This study demonstrates that the combined used of both methods can elucidate the trophic ecology of black scabbardfish, in situations where conventional methods alone provide insufficient data.

A total of 32 species were caught in surveys using Madeiran traditional longlines targeting the black scabbardfish (Aphanopus spp.) in the Canarian archipelago (northwest of Africa). Of these species, 15 belonged to the subclass Actinopterygii, 16 species to the Elasmobranchii, and one to the Holocephali. Species of the genus Aphanopus, the target species of this fishery, represented 38.5% of the catch in terms of the number of individuals and 36.4% in relation to the weight of the catch. The bycatch, which are non-target species of commercial interest, comprised only four species: two Teleostei species, Mora mora and Benthodesmus simonyi, which represented approximately 3.2% of the catch in number and 2.4% in weight; and two Elasmobranchii species, Centrophorus granulosus and Centrophorus squamosus, which represented 6.6% of the catch in number and 15.4% by weight. Deep-sea sharks were observed to be the most important component of the incidental catch (discarded species) of the traditional black scabbardfish longline fishery in the Canarian archipelago, representing 35.1% of the catch in number and 38.8% by weight. All of the Actinopterygii species were present in a proportion of less than 1%. The deep-sea shark species that were most frequent in the catches were Zameus squamulosus (44.9%), Deania hystricosa (14.7%), C. squamosus (13.5%), Centroscymnus coelolepis (6.7%) and Etmopterus princeps (5.1%). The ratio between the commercial catch (targeted species and bycatch) and the incidental catch was 1:1 in number of individuals. The ratio between the catch of the target species and the deep-sea sharks was 1:1 in number of individuals and in weight. The proportion of immature sharks constituted 31.7% of the total of all sharks caught.

The preparation of protein hydrolysates from black scabbardfish (Aphanopus carbo) by-products (BSB) was studied as an alternative for the upgrading of this raw material. Different levels of Protamex™ were used in the hydrolysate preparation and the peptides obtained and the lipids present in each of the four fractions obtained after centrifugation of the hydrolysed material were characterized. The nitrogen solubilization achieved was around 83% and degree of hydrolysis (DH) was about 57%. A high proportion of the peptides had molecular weights lower than 1000 Da. The highest percentage of oil remained in the emulsion (50–65%) and the highest percentage of free oil obtained was ca. 36%. The fatty acid profile of lipids present in the BSB and in the different fractions was similar. The triacylglycerols were dominant in all fractions and the highest percentage of phospholipids was detected in the oil from sludge and hydrolysate, followed by the emulsion but they were not present in the free oil. Cholesterol and cholesterol esters were detected in all fractions at low levels. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity and the reducing power of BSB hydrolysates increased with increasing DH. However, the hydroxyl scavenging activity decreased with DH.

The main biological characteristics for black scabbardfish in the Canary Islands waters were established, focusing on its reproductive behaviour and strategy and its growth pattern. The sex proportion differs significantly from the 1:1 ratio, being clearly unbalanced towards the females. The sex ratio according to depth clearly shows the presence of male and female individuals in all the studied layers, thus sex segregation does not happen according to depth. The Canaries can be considered to be a reproduction site for A. carbo , since samples showing all stages of maturity have been observed. The gonadosomatic index (GSI) showed that the mean values were higher in the third and fourth quarters of the year. The index values clearly allow the differentiation of the individuals in resting or in spent (II and V) stages from individuals in ripe or in ripe and running stages, indicating that index levels higher than 2 are typical of maturation followed by spawning process. Up to twelve marks, assumed to be annuli, were visible in the sampled otoliths. Three to five years old were the dominant age classes and only 7.7% of fish were 7 years old or older. Age estimates ranged between 2 and 8 years for males and between 2 and 12 years for females. Estimated growth parameters were: L ∞ = 1477 ± 18.73 mm; k = 0.200 ± 0.016 year −1 ; and t 0 = −4.58 ± 0.413 year. Biological aspects of the black scabbardfish suggest that this species has a generalist life-history strategy.

Aphanopus carbo fishery is economically relevant in Portugal (Madeira Archipelago) since the 19th century and an important diet component of its inhabitants. However, Hg levels in this species are a cause of concern due to the insufficient knowledge of Hg subcellular distribution, accumulation and detoxification mechanisms. Hg concentrations (total and subcellular) and metallothionein-like proteins (MTs) were measured in the gills, muscle and liver of A. carbo of different size (50-150 cm) to assess Hg subcellular distribution and the role of MT in Hg binding. Total Hg concentrations in A. carbo decrease from liver to gills and increase exponentially with fish length in all tissues. Hg subcellular distribution in muscle and liver decreased from insoluble > high molecular weight proteins and heat-treated cytosol where MT occurs highlighting the role of the insoluble fraction in Hg distribution. In the gills, Hg was mainly in the soluble fraction except for 75-100 cm specimens, whose Hg distribution was similar between soluble and insoluble factions. The variation of MT with size is different from that of Hg. MT levels in the gills decrease with size/age and is unrelated with Hg concentrations. In the muscle although decreasing with size/age, MT is inversely proportional to Hg. In the liver, however, MT is directly proportional with size/age and to the Hg accumulated (total and HTC subcellular fraction) highlighting an age related change in these two parameters and the importance of MT in detoxifying Hg in this tissue. Due to Hg concentrations present in the muscle (used for human consumption) and liver (consumed mainly by fisherman) consumption of A. carbo should be taken with caution in a population with such an important seafood weekly intake. info:eu-repo/semantics/publishedVersion

Total mercury, cadmium and lead concentrations were measured in black scabbard fish (Aphanopus carbo), caught off Madeira and the Azores archipelagos (Portugal). The metal contents were expressed in mg kg(-1) wet weight. The mean mercury levels in liver were 4.50 and 2.37 whereas, in skin, such values were 0.59 and 0.36 (Madeira and Azores, respectively). Onaverage, the muscle content was around 0.9 in fish from both areas. Cadmium maximum levels in muscle and skin were found in Azores samples (0.09 and 0.11, respectively). Mean lead contents in all samples were always below than 0.10. In general, the results obtained did not allow the establishment of any relationship between metal accumulation and fish weight or length. According to the permissible WHO and FAO levels, these results, suggest that this species does not represent a risk for human consumption if the liver is excluded and the edible part consumed with moderation. (c) 2006 Elsevier Ltd. All rights reserved.

Samples of monkfish (Lophius piscatorius), black scabbard (Aphanopus carbo), blue ling (Molva dypterygia), blue whiting (Micromesistius poutassou) and hake (Merluccius merluccius) were obtained from 400 to 1150 m depth on the continental slope of Rockall Trough west of Scotland. Muscle, liver, gill and gonad tissue were analysed for arsenic, cadmium, copper, lead, mercury and zinc by various atomic absorption techniques. Median concentrations of arsenic in the muscle tissue ranged from 1.25 to 8.63 mg/kg wet weight; in liver tissue from 3.04 to 5.72 mg/kg wet weight; cadmium in muscle tissue from

Three major fleets of high sea trawlers practising deep-water fishing are defined. Altogether, these fleets catch more than 90% of the French landings of deep-water species. A multiplicative model has been adjusted to monthly catch per unit effort (CPUE) weighted by effort to estimate annual abundance indices for the main deep-water species exploited since the late 1980s (Coryphaenoides rupestris, Hoplostethus atlanticus, Aphanopus carbo, Centroscymnus coelolepis and Centrophorus squamosus) and for the main other species caught by these fleets (Pollachius virens, Molva dipterygia and Molva molva). For the deep-water species, the CPUE trends are not consistent between fleets. The differences are interpreted to be due to technical changes and the indices from the fleet of larger specialised deep-water trawlers is considered to be the most representative of the actual fish abundance. For saithe and blue ling the declining trend in CPUE previously documented are observed again with slight differences in slopes probably due to method. The CPUE of deep-water species show strong declining trends suggesting severe impact of the fishery. However, declining CPUE is a normal feature of any new fishery. The possible effect of the fishing strategy on the amount of effort counted as species directed effort cannot be excluded because the catch and effort data available is detailed by statistical rectangles while the proper scale would be the trawl haul.

1. 1. The thermal properties of intestinal alkaline phosphatase were investigated with three species of deep-water fish in the temperature range of 0–70°C. 2. 2. A relationship was found between the thermal stability of the enzyme and the fish origin. 3. 3. Maximum activity of alkaline phosphatase of the fish that originated in tropical water, namely, Aphanopus carbo and Epigonus telescopus was 60°C, whereas the respective maximum enzyme activity of Etmopterus princeps that originated in the burial zone was 30°C. 4. 4. A breakpoint at 10°C in the Arrhenius plot of enzyme activity in the case of A. carbo and a lack of a break point in the case of E. telescopus and E. princeps , are in accordance with the stenothermic nature of the former and the everythermic nature of the two latter fish species.

A total of over 28,000 benthic and benthopelagic fish belonging to 34 families and comprising at least 85 species were collected from the Hebridean Terrace in the Rockall Trough between soundings of 500 and 2000 m. Commercial type trawls (20.6 m Granton or 140 foot German bottom trawls) fished on paired warps at 33 stations accounted for 89% of all individual caught, the remainder being caught by a 16.4 m prawn trawl fished on a single warp (22 stations) and a 3 m Agassiz trawl (12 stations). The stations sampled, with a few exceptions, fell into discrete bathymetric zones separated by increments of approximately 250 m and different combinations of nets were used at each of these zones. The catch composition of the commercial trawls differed from those of the other nets. The most obvious difference was that squalid sharks, the alepocephalid Alepocephalus bairdii and the black scabbard fish Aphanopus carbo were important in the commercial type trawls but were absent or poorly represented in the other nets. Net size and towing speed were considered to be important factors influencing the catch composition. Net selectivity was most apparent on the upper and mid slopes but less apparent on the lower slopes. Relatively few families contribute to the total biomass at a given bathymetric zone and because the families Squalidae and Alepocephalidae contribute significantly to the biomass on the upper and mid slope it is therefore concluded that small nets must grossly underestimate the biomass at these depths. The greatest biomass occurred at mid slope depths (750–1000 m).