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The recently described Mediterranean goby species, Buenia massutii, was found at the deep shelf in the Gulf of Cádiz (north-eastern Atlantic Ocean). The identification of the specimen was performed using morphological analysis and molecular techniques ; including the sequencing of the mitochondrial genes Cytochrome c Oxidase I (DNA barcode) and Cytochrome b. The sequences for Cytochrome b is presented for the first time for B. massutii. The limited migration capability and behaviour of small benthic gobies, the short lifespan of Buenia species, and the oceanographic characteristics of the Strait of Gibraltar suggest the existence of an independent Atlantic population of B. massutii.

The Blackspot Seabream (Pagellus bogaraveo) is one of the most important commercially exploited fish species for the Spanish and Moroccan fleets which operate in the Strait of Gibraltar. In recent years, the landings of Blackspot Seabream in the main ports have decreased significantly with respect to previous periods of maximum catches, which makes it necessary to properly assess the abundance before establishing a management plan to make the fishery sustainable over time. In this chapter, we describe three different approaches to assess the abundance of this species in the Strait of Gibraltar. The results of three approaches tested (LCA/VPA, Gadget model, and SimFish model) point out that from 2010 the stock is kept at very low levels that oscillate between 900 and 1600 t, which supposes that the total biomass is between a 16% and 29% of the potential biomass. Additionally, the reference point values estimated by LCA/VPA and Gadget (F0.1 = 0.12–0.17) imply a clear overexploitation of the resource which is reinforced by the SimFish model results indicating that at least the 64% of abundance variation is a consequence of the fishery component.

This document is the product of an expert group under the auspices of the International Council for the Exploration of the Sea and does not necessarily represent the view of the Council. The Working Group on Nephrops Surveys (WGNEPS) is the international coordination group for Nephrops underwater television and trawl surveys within ICES. This report summarizes the national contributions on the results of the surveys conducted in 2019 together with time series covering all survey years, problems encountered, data quality checks and technological improve-ments as well as the planned for survey activities for 2020. In total, 19 surveys covering 25 func-tional units (FU's) in the ICES area and 1 geographical subarea (GSA) in the Adriatic Sea were discussed and further improvements in respect to survey design and data analysis, standardiza-tion and the use of most recent technology were reviewed. A new survey summary template by FU/GSA has been developed and adopted for future re-ports, which shall allow the data end users to extract the most relevant information on the survey results in a more easy way.Necessary actions and reviewer comments were addressed on the draft version of the Series of ICES Survey Protocols (SISP). Similarly, the working group reviewed the specifications for a Nephrops underwater TV database to be established at the ICES data centre and agreed on fur-ther action on this issue.First results from field studies on behaviour aspects of burrow emergence using bottom cages monitored by an automated camera system and on short-range migration using acoustic tracking are now available.Comparison of standard definition (SD) and high definition (HD) indicates the change to HD system mounted with a different camera angle may affect the detection rate and may thus require a revision of bias correction factors. New image reviewing software allows an easier way of an-notation of burrows than previous mosaicking methods, which has further advantages for inter-preting the results from different counters and for providing quality assured material for deep learning methods. The WG members agreed to collect information on burrow diameter size us-ing HD images and burrow annotation or mosaicking software because a change in the burrow size distribution may indicate recruitment events and the size of the burrow has an effect on bias correction factors in general. Automatic burrow detection based on deep learning methods applied to a test data set with an-notated burrow counts from a HD camera system showed promising results. The WG members were encouraged to provide more material with annotated burrow counts for further develop-ment of machine learning tools.

10 pages, 7 figures, 2 tables, Understanding the processes that influence octopus abundance is important in order to manage the fishing grounds and offer advice on the exploitation of this important resource. Fluctuations in abundance of exploited stocks may be due to a great variety of factors. However, in short-lived animals such as cephalopods, in which abundance depends on strength of the recruitment, it is well known that population abundance is highly influenced by the environmental conditions. In this study we investigated the relationship between octopus (Octopus vulgaris) catches from the fishery located in the area off the Gulf of Cadiz (Spanish South Atlantic Region) and several hydrographic and oceanographic parameters such as sea surface temperature, surface chlorophyll-a, inorganic surface turbidity and climatic indicators such as the NAO index, rain, WeMoi Index, AMO index and or Guadalquivir River discharges. In addition, a recruitment index was obtained from fishery-independent surveys, which was also used to investigate its effect on annual catches. Results revealed that abundance of octopus showed a significant negative relationship with rain in the previous year as well as a positive effect of the recruitment index. We have obtained a model using the rain and the recruit index to forecast the catches. This model explained a high percentage of variation in annual catches and was used to forecast the next year’s catch providing results within the expected confidence intervals. This represents a potentially useful tool to guide fishery managers since no assessment of the species is currently conducted in the area, This work was supported by the Research Program of Andalucia, Spain (project number RNM 1953) and the mobility program “Salvador Madariaga” of National Research program of Spain (grant numbers PRX16/00001)

The structure and composition of megabenthic epifauna from the mud volcano field known as El Laberinto and the nearby soft bottoms were analysed. Species abundance and biomass data were obtained from the Arrastre Region Sur-Atlantica bottom trawl surveys carried out routinely from 1993 to 2009. A high biodiversity of megabenthic epifauna was found with a total of 272 species. Univariate community descriptors displayed similar values in zones inside and outside El Laberinto and in different seasons with the exception of abundance, which was larger in the autumn, especially in the zone nearest the mud volcano field. The dominant species in terms of abundance in all zones were similar and included Pasiphaea sivado, Plesionika martia, Parapenaeus longirostris, Nezumia aequalis, Chimaera monstrosa, Galeus melastomus and Etmopterus spinax. This information could be useful for increasing knowledge on biodiversity and the occurrence of commercial species and for establishing conservation strategies for protection...

This paper aims to investigate the potential interest of using a Vessel Monitoring System (VMS) based on GPRS/GSM (Global System for Mobile Communications) technology to obtain a better estimation of fishing activity and distribution of a small-scale artisanal fleet, for which the European satellite-based system is not available. Since the early 1980s, the artisanal fishery targeting blackspot seabream (Pagellus bogaraveo), commonly known as “voraz”, has been developing along the Strait of Gibraltar area. Up to now the fishing effort was estimated using the number of sales, a proxy for the number of fishing days. This measure does not, however, capture the “missing effort”, i.e., fishing days resulting in no catch or not enough catch to be sold at public auction. The European satellite-based VMS provides information about the dynamics of different fishing fleets, but is not installed on small vessels (

The present paper reports for the first time for Mozambique waters the distribution, abundance and species assemblages of cephalopods in the outer shelf and upper/middle slope (100 – 700 m depth) from data collected in spring of 2007 during the “Mozambique 0307” bottom-trawl survey. A total of 129 hauls were performed following a random stratified sampling scheme in the different sectors and bathymetric strata. The biomass estimates were computed by the swept area method. Cephalopod species accounted for 8.4% of the total biomass captured, with a total of 50 species belonging to 13 families. The most important families in terms of species richness were Octopodidae and Sepiidae with 10 representatives each. The most abundant species was the omastrephid Nototodarus hawaiiensis, present in all sectors. The second most abundant species in terms of biomass was Sepia acuminata, followed by the Veladona togata (Octopodidae) mainly between 400 and 600 m depth. The highest biomass estimates were recorded in the sectors named Bazaruto B and Boa Paz, between 200 and 400 m depth. Species assemblages were analysed with the Bray-Curtis similarity index and the group average clustering method was applied, revealing three cephalopod assemblages : the shelf community (100-200m), a wide transitional zone between shelf edge-upper slope (200-600 m) and the middle slope (600-700 m), mainly characterised by Sepia species, Nototodarus hawaiiensis, and Histioteuthis species, respectively. The diversity indices showed a higher diversity in Sofala, in the north of the study area, and in the shelf community in all sectors., Sí