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A survey on shellfish consumption preferences was conducted in the Eastern Atlantic archipelago of Madeira. A total of 402 valid questionnaires were collected from locals older than 15 years old. Gender, age, highest education level, work status and salary were considered in the sample composition. Participants were inquired about frequency, amount and risks associated with consumption, as well as concerns regarding the freshness of seafood. Shellfish appears to be consumed less than once a week, and 79.1% of these consumers prefer limpets. GLM analysis showed that total salary amount was the demographic variable which most affects seafood consumption. The results indicated that the majority of the respondents consume limpets less than once a week, in an amount that varies between a quarter and a half dose. With regard to health concerns, most respondents are conscious of the importance of products’ freshness and approximately half of them are aware of the existence of risks associated with consumption. In general, the awareness about freshness and possible risks of consumption is dependent on the level of education. Limpets are preferably consumed during summer, both grilled and cooked, respectively. The present study provides preliminary information on shellfish consumption trend in the archipelago of Madeira. Raising the awareness of seafood consumers in line with a health surveillance network in preparation in Macaronesia could be an important tool for spreading information related to the risks associated to its consumption.

Coastal erosion impact on low-lying sandy shorelines represents a worldwide problem, which is particularly felt in various segments of the Portuguese coast where this geomorphological type represents 42% of its total length. Beach nourishment is a viable engineering alternative for shore protection and the assessment of offshore sources of beach-fill material is an essential aspect when implementing this mitigation strategy. The CHIMERA project carried out a multidisciplinary inspection on four segments of the west Portuguese coast to assess their potential as offshore borrow areas for beach nourishment. Altogether, these segments covered an area of c . 35 km 2 , at water depths between 20 and 42 m. They were surveyed using multibeam, sub-bottom profiler, ultra-high resolution multichannel seismics and a set of 126 surface samples and 72 vibrocores (with 3 m long each). To comply with the Portuguese legislation, sand types were assessed by granulometric and chemical analyses for evaluating the quality of sediments in terms of contamination. High-resolution magnetic surveys were conducted to find potential archaeological artefacts. The adopted methodology proved to be adequate to quantify and describe the spatial distribution of useful sediment volumes, supporting the ongoing Integrated Coastal Sediment Strategy for mainland Portugal.

Background The blue marlin (Makaira nigricans) is a vulnerable migratory fish inhabiting tropical and subtropical pelagic waters of the Atlantic, Pacific and Indian Oceans. The biology and spatial ecology of the species in the eastern North Atlantic is poorly understood, despite being exploited in the region by recreational and commercial fisheries. Here, we present results of the first study to use pop-up satellite archival tags to track blue marlin off Madeira, Portugal (n = 3) and obtain insights into the movements and habitat use of the species within the eastern North Atlantic. Results Blue marlin were tracked for 24 to 83 days, moving from Madeira to pelagic waters off the Canary Islands, Cape Verde Islands, as well as along the continental shelf brake of Europe and Africa. Blue marlin spent 71% of their time in the upper 5 m and 89% in the upper 50 m, though all individuals dived to depths over 200 m (maximum: 336 m). Temperature at depth ranged from 12 to 28.6 °C, but the greatest proportion of time was spent in waters between 20 and 26 °C. Detailed depth and temperature time-series data were obtained from a tag recovered eight years later. These data show clear diel differences in depth use, involving consistent use of the surface at night and deeper dive activity during the day, predominately to depths greater than 50 m. Conclusions The highly migratory patterns of this vulnerable species in the eastern North Atlantic highlights the need for both local and international conservation measures. Depth-use patterns, particularly the high usage of the upper 5 m of the water column, make them susceptible to surface longline fisheries.

Background Seamounts are underwater mountains which typically rise rather steeply at least several hundred meters above the deep-sea floor. These geological features interrupt water flow and hence may induce changes in the circulation of different water masses, in turn causing different physical and biological effects. For this reason, seamounts are biodiversity hotspots, housing a wide number of species, as is with the case of the Seine and Unicorn seamounts, which are a part of the Madeira-Tore seamount chain located between Portugal mainland, southwestern Europe and Madeira archipelago (NE Atlantic). Methods Fisheries independent surveys allowed the collection of Chondrichthyes specimens from the Seine and Unicorn seamounts. Individuals were caught over the course of two research cruises, first in 2004 and later in 2017, with species distribution ranging from the summit down to 2500 m of depth. Results Fifteen species belonging to 7 different taxonomical families were collected in the two surveyed areas. Two species were recorded for the first time and added to the checklist of the Seine seamount (Centrophorus granulosus and Somniosus rostratus), and three species for the Unicorn seamount (C. granulosus, Centroscymnus coelolepis and Centroselachus crepidater). Distribution and frequency of occurrence for the collected species were evaluated in relation to depth. Conclusions This work is a valuable contribution to the knowledge of seamount-associated fish fauna. Moreover, the checklist of sharks, rays and chimaeras was updated for the Seine and Unicorn seamounts, summing up 20 species.

Aims Rising sea-level following the Last Glacial Maximum lead to fragmentation of coastal limpet populations between islands of the Archipelago of Madeira. This fragmentation is reinforced by recent heavy exploitation reducing effective population size on Madeira Island. We use the limpet P. aspera to understand how the role of processes at different time scales (i.e. changes in the sea level and overexploitation) can influence the genetic composition of an extant species, relating these processes to reproductive phenology and seasonal shifts in ocean currents. Location Madeira Island, Porto Santo and Desertas (Archipelago of Madeira, NE Atlantic Ocean). Taxon The limpet Patella aspera. Methods Twelve microsatellite genetic markers were used. A power analysis was used to evaluate the power of the microsatellite markers to detect a signal of population differentiation. Long-term past migrations were assessed using a Bayesian Markov Montecarlo approach in the software MIGRATE-n to estimate mutation-scaled migration rates (M = m/μ; m, probability of a lineage immigrating per generation; μ, mutation rate). Two scenarios were evaluated using an Approximate Bayesian Computation (ABC) in the software DIYABC 2.1 (i) Scenario 1: considered a population scenario from a reduced Ne at time t3 to a higher Ne at time t2; and (ii) Scenario 2 considering a reduction of Ne from a time t3 to a time t2. Results Colonization of the archipelago by Portuguese settlers six centuries ago probably led to an important decrease in the genetic diversity of the species (Ne). Contemporary gene flow strongly support a pattern of high asymmetric connectivity explained by the reproductive phenology of the species and spatio-temporal seasonal changes in the ocean currents. Spatio-temporal reconstructions using Bayesian methods, including coalescent and Approximate Bayesian Computation (ABC) approaches, suggest changes in the migration patterns from highly symmetric to highly asymmetric connectivity with subtle population differentiation as consequence of post-glacial maximum sea level rise during the Holocene. Main conclusions Our results suggest that anthropogenic activity could have had serious effects on the genetic diversity of heavily exploited littoral species since the end of the Pleistocene, probably accelerating in recent years.

According to the most recent taxonomical revision, the deep-sea dogfish genus Deania encompasses four species. Three of them, D. calcea, D. profundorum, and D. hystricosa, occur in the North Atlantic. Whilst D. profundorum can be identified by the presence of a subcaudal keel, the other two species are not easily visually distinguished. Uncertainties over identification raises concerns over stock units and whether management plans are adequate. In this study we compared onboard visual identification of Deania specimens, with morphological inspection of skin denticles under stereo microscope and with independent molecular taxonomical assignment using two molecular markers. Particular emphasis was paid to specimens identified as D. calcea and D. hystricosa in the NE Atlantic where these species potentially occur sympatrically and may be easily confused. In the past the species have been discriminated on the basis of the size of skin denticles (skin roughness), but our study showed that the crown length of skin denticles covaries with size (and sex), irrespective of species, and therefore this is not a reliable morphological character and should not be used to discriminate between the two species. Phylogenetic analyses did not indicate that D. hystricosa to be a distinct lineage from D. calcea. Interestingly, however four individuals (specimens from: UK, Azores Is., Madeira Is. and Seine seamount) formed a well-defined sub-clade nested within the D. calcea clade, possibly a signature of a past vicariance event or a result of coalescent stochasticity.

Este artículo contiene 24 páginas, 5 figuras, 3 tablas., This work is the result of an international research effort to determine the main impacts of the COVID-19 pandemic on marine recreational fishing. Changes were assessed on (1) access to fishing, derived from lockdowns and other mobility restrictions; (2) ecosystems, because of alterations in fishing intensity and human presence; (3) the blue economy, derived from alterations in the investments and expenses of the fishers; and (4) society, in relation to variations in fishers’ health and well-being. For this, a consultation with experts from 16 countries was carried out, as well as an international online survey aimed at recreational fishers, that included specific questions designed to capture fishers’ heterogeneity in relation to behavior, skills and know-how, and vital involvement. Fishers’ participation in the online survey (5,998 recreational fishers in 15 countries) was promoted through a marketing campaign. The sensitivity of the fishers’ clustering procedure, based on the captured heterogeneity, was evaluated by SIMPER analysis and by generalized linear models. Results from the expert consultation highlighted a worldwide reduction in marine recreational fishing activity. Lower human-driven pressures are expected to generate some benefits for marine ecosystems. However, experts also identified high negative impacts on the blue economy, as well as on fisher health and well-being because of the loss of recreational fishing opportunities. Most (98%) of the fishers who participated in the online survey were identified as advanced, showing a much higher degree of commitment to recreational fishing than basic fishers (2%). Advanced fishers were, in general, more pessimistic about the impacts of COVID19, reporting higher reductions in physical activity and fish consumption, as well as poorer quality of night rest, foul mood, and raised more concerns about their health status. Controlled and safe access to marine recreational fisheries during pandemics would provide benefits to the health and well-being of people and reduce negative socioeconomic impacts, especially for vulnerable social groups., This work was funded by the Xunta de Galicia (RECREGES II project under Grant ED481B2018/017, and Grupo de Referencia Competitiva GI-2060 AEMI, under Grant ED431C2019/11). PP acknowledges economic support of the project Grupo de Trabajo Sobre Pesca Marítima Recreativa en España, funded by the Fundación Biodiversidad of the Spanish Ministerio Para la Transición Ecológica y el Reto Demográfico, co-funded by the European Maritime and Fisheries Fund. SV acknowledges the financial support of the EQUALSEA project ERC Consolidator Grant Agreement No. 101002784 funded by the European Research Council, and the CYTED program for the ECOMAR Network. AML, CS, and MW have been co-funded by the European Commission’s Data Collection Framework (DCF). CS acknowledge founding from the Danish Rod and Net Fish License funds (Project No. 39122). The CCMAR affiliated authors acknowledge Portuguese national funds from FCT-Foundation for Science and Technology through project UIDB/04326/2020. MaR acknowledges FCT funding through a post-doctoral grant (SFRH/BPD/116307/2016). AA acknowledges funding of FAPES, Fundação de Amparo à Pesquisa e Inovação do Espírito Santo, Brazil - PROFIX program 10/2018 - T.O.: 348/2018 for AA postdoctoral scholarship. JR-F acknowledges funding of Participatory Fishing Monitoring accomplished by the ICHTUS Soluções em Meio Ambiente Ltda. KF was funded by the tourist fishing project (“Kartlegging av Turistfiske”), which is part of the Coastal Zone Ecosystem Program at the Institute of Marine Research of Norway. JG-C and VS were funded in part by a contract with the Regional Fisheries and Aquaculture Service - Autonomous Community of the Region of Murcia - Spain (with funds from the European Maritime and Fisheries Fund) and the project “MaReFish” financed by the MedPAN network under its “Small Projects – 2018” call. JA was supported by a Ramon y Cajal Grant (Grant No. RYC2018-024488-I) and received funding from the CLOCKS (Grant No. PID2019-104940GAI00) and JSATS (Grant No. PIE202030E002) projects funded by the Spanish Ministry of Science and Innovation (MICINN). VSB is supported by a “Juan de la Cierva Incorporación” research fellowship (IJC2018-035389-I) granted by the Spanish Ministry of Science and Innovation (MICINN). HS acknowledges financial support by the Federal Ministry of Education and Research of Germany in the framework of marEEshift (Project No. 01LC 1826B).

Topshells play a pivotal role in intertidal rocky ecosystems and are adapted to harsh thermal and hydric stress. Phorcus sauciatus, a common grazer in the Macaronesian region (Madeira and the Canaries), has rarely been studied due to its restricted geographic distribution compared with Phorcus lineatus. Monthly samples were taken throughout 2017 to analyse biological parameters and evaluate the harvesting effect on the stocks of this species in Madeira. Individuals of the first age classes (−1, corresponding to a Y/R of 0.023 g. Currently, Phorcus sauciatus seems to be moderately exploited in Madeira, but urgent conservation measures, such as a landing obligation, the establishment of a minimum catch size of 15 mm length, and a closed season (February–May), are warranted to preserve stocks of this species in the medium to long term.

Natural history collections from museums and private institutions can play an important role supporting decisions in biodiversity conservation. Seahorse populations have suffered a worldwide decline, while many areas remain data deficient including areas subjected to heavy commercial trading, such as the coasts of West Africa. In this work, seahorse collections from museums and public institutions in Macaronesia (Azores, Madeira and the Canary Islands) were initially reviewed (1) to identify specimens not previously determined, and (2) to correct species determinations from Macaronesia and adjacent West African coasts. The morphological data (3) were tested for phenotypic variation of seahorses within and between Macaronesia and adjacent West African coasts. The presence of Hippocampus hippocampus (short-snouted seahorse) and Hippocampus algiricus (West African seahorse) was confirmed for the area, including new sightings along previous geographical distribution ranges. Morphological analyses partitioned seahorse species and several morphotypes within and between Macaronesia and adjacent West African coasts. This phenotypic plasticity was associated with cranial morphology. Such differences are a useful tool for tracking seahorse populations of varying species and origins. New information presented here, is valuable for improving the management and conservation of seahorses, particularly in areas threatened by illegal trading or other anthropogenic activities.

The structure and composition of deep-sea fish assemblages living on the middle slope off NW Africa (26–33° N) were investigated. Data were collected by six commercial trawlers during experimental fishing (1027 hauls) at depths between 800 and 1515 m. A total of 1,115,727 fish specimens, belonging to 37 families and 96 species (24 Elasmobranchii, 5 Holocephali, and 67 Actinopteri) were collected with bottom trawls. The deep-sea demersal fish fauna off NW Africa is dominated by fishes of the family Macrouridae, followed by the Moridae and Alepocephalidae families. The main abundant species were Trachyrincus scabrus , Bathygadus favosus , Mora moro , Alepocephalus productus , Nezumia aequalis and Bathygadus melanobranchus. PERMANOVA analysis showed differences in demersal fish assemblages among bottom types, depth strata and between areas (north and south of parallel 30° N), with the area being the most influential factor followed by the type of substrate. PERMANOVAs computed separately for each area showed significant differences among the bottom types and depths in both areas. SIMPER analysis revealed that B. melanobranchus and B. favosus , which occurred at higher abundances in the area ≥30° N, were the species that were best discriminated between areas; whilst T. scabrus and M. moro occurred at higher abundances in the area N. aequalis , B. favosus , B. melanobranchus , Deania hystricosa , Aphanopus intermedius , Coelorinchus labiatus and Halosaurus johnsonianus were restricted or more abundant in the area ≥30° N, and functioned as the discriminating species that most contributed to the average dissimilarity between areas. T. scabrus , M. moro , Alepocephalus productus and Alepocephalus bairdii were more abundant in the area 2 ) showed a decreasing pattern: i) with depth in both areas, north and south of parallel 30° N, and ii) with depth on each type of substrate, except on cold coral bottoms. Hydrolagus mirabilis , Gadomus dispar , Nettastoma melanurum , Halosaurus ovenii , Chimaera opalescens , A. productus , Hoplostethus mediterraneus , Apristurus laurussonii and Trachyscorpia cristulata echinata showed a deeper Center of Gravity at latitudes ≥30° N, with differences in depths from 299 to 110 m compared to the area at latitudes T. scabrus , Anoplogaster cornuta , B. favosus , Centrophorus squamosus , B. melanobranchus and A. bairdii showed a similar depth Center of Gravity, with differences in depths lower than 21 m.

As part of an annotated checklist of fishes of the archipelago of Madeira, a list with all cartilaginous fishes recorded from the archipelago is presented. The list contains 67 species of sharks, rays and chimaeras, whose presence in the area the authors consider confirmed. Another 14 species previously referred for the area are now considered dubious records and five species are withdrawn from the list. Centrophorus uyato is here recorded for the first time from Madeira. Three species (Mitsukurina owstoni, Odontaspis noronhai and Chimaera opalescens) are so far only present in Madeira within Macaronesia. The 67 confirmed species are based on occurrences, substantiated by specimens in natural history museum collections or other published evidence. For all species, the first reference is given, as well as other relevant references for the archipelago and remaining Macaronesia.

The deep-sea sharks associated as by-catch of the Madeiran midwater drifting longline fishery for scabbardfishes (Aphanopus spp.) were investigated by means of an experimental survey at 800-1200 m depth within the Canary Islands Exclusive Economic Zone, whose fishing grounds have been exploited during the past 15 years. Nine species of chondrichthyans were identified, belonging to five families: Pseudotriakidae, Centrophoridae, Etmopteridae, Somniosidae and Chimaeridae. Data on length, weight and sex ratio for the 436 chondrichthyan individuals caught in the March 2009 survey are given. Several voucher specimens of each species caught were deposited in the collections of the Natural History Museum of Funchal. Se investigaron los tiburones de profundidad en las capturas accesorias de la pesquería de palangre de deriva de media agua que tiene por objetivo el sable negro (Aphanopus spp.) mediante una campaña experimental en la Zona Económica Exclusiva de Canarias a profundidades de 800 a 1200 m, en caladeros que han venido siendo explotados en los últimos 15 años. Se identificaron nueve especies de condrictios pertenecientes a cinco familias: Pseudotriakidae, Centrophoridae, Etmopteridae, Somniosidae y Chimaeridae. Se aportan datos de talla, peso y proporción de sexos para los 436 ejemplares de condrictios capturados en la campaña de marzo de 2009. Los especímenes de referencia capturados fueron depositados en las colecciones del Museo de Historia Natural de Funchal.

This work investigated the biology of Chaceon affinis in two isolated populations of the Atlantic Ocean, including depth distribution, sexual structure, reproductive patterns and intermoult period. Males were larger and heavier than females. Mean size decreased with depth for both males and females. The highest abundance was found at 600–799 m of depth for males and at 800–999 m depth stratum for females. The highest abundance of ovigerous females was found at the 800–999 m depth stratum. Of the different ovaries’ colour or colour shades recorded, only six categories were histologically characterized. The presence of spermatophores in the spermatheca of females in carapace stages II and III suggests that spermatophores are viable and used during the intermoult period. The size at sexual maturity in females was estimated at 104.4–104.7 mm carapace width (CW) in Madeira, and 109.3–110.5 mm CW in the Canary Islands. Only three categories of testes were identified. Mature testes consisted in a large mass, with highly coiled vasa deferentia visible to the naked eye. The size at sexual maturity in males was estimated at 113.8 mm CW in Madeira and 118.9 mm CW in the Canaries. The relative growth of males showed significant changes along the ontogeny and size at which allometric growth changes, as an indicator of morphometric maturity, occurred between 103.2 and 103.6 mm CW in Madeira and between 111.4 and 113.1 mm CW in the Canaries. In females, size at which allometric growth changes was found for maximum width of fifth abdominal somite (AS5W) at 98.2 mm CW in Madeira and 103.0 mm CW in the Canaries. The size at maturity obtained for C. affinis indicates that the minimum landing size (MLS) should not be set smaller than 125 mm CW in Madeira and 130 mm CW in the Canaries. This conservative MLS, higher than length at functional maturity, would safeguard immature individuals until they reach the size at which they can contribute to the reproductive capacity of the population. Ovigerous females were observed from October to April in Madeira, and in all months in the Canaries. Moreover, the observation of berried females in the last developmental stage in all quarters of the year suggests that gonad maturation and release of larvae are asynchronous throughout the spawning season. A total of 138 crabs with CW between 96 and 154 mm were tagged off Madeira. Of these, nine were recovered in the same area, more than 900 days after tagging. Eight of the recaptures were females with a wide range of CW confirming intermoult periods exceeding three years with expected growth per moult of less than 20 mm CW.

The deep-sea sharks associated as by-catch of the Madeiran midwater drifting longline fishery for scabbardfishes (Aphanopus spp.) were investigated by means of an experimental survey at 800-1200 m depth within the Canary Islands Exclusive Economic Zone, whose fishing grounds have been exploited during the past 15 years. Nine species of chondrichthyans were identified, belonging to five families: Pseudotriakidae, Centrophoridae, Etmopteridae, Somniosidae and Chimaeridae. Data on length, weight and sex ratio for the 436 chondrichthyan individuals caught in the March 2009 survey are given. Several voucher specimens of each species caught were deposited in the collections of the Natural History Museum of Funchal.

Fish assemblages in Cais do Carvao Bay. Madeira Island, a proposed marine protected area (MPA). were determined from a diver visual census. A total of 32 transect counts were performed. Habitats sampled included sandy bottom, rocky boulders, vertical walls and rocky outcrops. Species richness, diversity, density, trophic structure, size and spatial organization were documented for the fish assemblages. Forty-four species from 23 families were encountered: 32% belonged to Sparidae (10) and Labridae (four). The greatest species richness (25) was observed in rocky boulder habitat at 10-15 m depth, while the lowest (five) occurred over a deeper sand habitat. The greatest density (760.5 individuals per 100 m 2 ) was recorded over rocky outcropping (20-25 m deep), and the lowest of 11-6 individuals per 100 m 2 was over a sand bottom at 10-15 m depth. Thalassoma pavo, Abudefduf luridus and Chromis limbata had higher densities on hard bottoms, while Heteroconger longissimus was the most abundant species in sand bottom habitats. No significant differences were detected for all indices calculated among depth intervals for sand and rocky boulder stations. Sand and rock boulder substratum, however, differed significantly for the 10-15 m depth stratum.

The smalleyed rabbitfish, Hydrolagus affinis (de Brito Capello, 1868) (Chimaeridae), is recorded from the archipelago of Madeira for the first time, based on seven specimens caught between 1200 and 2500 m depth. This record extends the previously known range of distribution of this species, and also confirms its vertical dis - tribution down to 2500 m. Additional material collected from the Canary Islands and the Azores was used for comparison.