Study and evaluation of the biomass of the anchovy in the Bay of Biscay within the National Sampling Plan.

This campaign to evaluate deep demersal resources on the coasts of Algeria responds to the need to update and expand the studies and evaluations carried out in the 1980s. During this fishing prospecting campaign, 55 catches were made between 200 and 800 meters deep, using bottom trawls. To determine the abundance and properties of the main fishing resources of Algeria, it was necessary to obtain prior knowledge of the characteristics of the seabed on the sampled fishing beaches. Likewise, the precise knowledge of the bathymetry and morphology of the bottom optimized the trawl work and, in short, the achievement of the fishing campaign. GOALS Image of ship's personnel releasing trawl - Bathymetric and morphological recognition of the seabed in the upper slope and the Algerian coast. - Know the biological structure of demersal communities subjected to exploitation in the upper and middle slope of the study area. - Obtain indices of abundance and biomass of the main deep demersal species (hake, monkfish, white prawn, Norway lobster and red shrimp). - Characterize the demographic structure of the main demersal species exploited on the slope, as well as its geographical and bathymetric distribution. - Collect data and collect samples (otoliths) from deep demersal species for growth and reproduction studies. WORK AREA The bathymetric surveys were carried out at night, in such a way that sufficient time was available to elaborate the bathymetric maps and digital terrain models. This allowed the selection of the haul zones and served as an electronic cartography for navigation.

The Algerian continental shelf, very narrow and rocky, is not conducive to bottom trawling. Its average length is 6 km, even in certain areas, the 500-meter isobath is 3 miles from the coast. Only in some gulfs in the west of the country (such as Oran), near the Alboran Sea, the platform reaches an extension above average. According to the Algerian Geographic Unit, it is estimated that only 1/3 of the surface is optimal for bottom trawling: 3,500 km2 up to 200 m depth and 7,000 km2 between 200 and 350 m. This limits the availability of demersal species and thus, rg / 1999 / xhtml "> of the total catches of these species (~ 25,000 Tm), about 4,000 (~ 20%) correspond to crustaceans, mainly prawns, which are caught between 200 and 400 m GOALS Determine the abundance and characteristics of the main demersal resources of Algeria. For this, the following partial objectives are proposed: - Know the biological structure of the communities exploited by the trawl fishery on the platform and the upper slope. - Obtain indices of abundance and biomass of the main species, such as mullet, sparids, hake, monkfish, white shrimp, Norway lobster, pink prawn, Moorish prawns, octopus and cuttlefish. - To determine the characteristics of the demographic structure of these species, as well as to know their geographical and bathymetric distribution. - Collect data on the state of maturity, size and weight, and collect biological samples of demersal species for growth and reproduction studies.

Study and evaluation of the biomass of the anchovy in the Bay of Biscay within the National Sampling Plan.

Study and evaluation of the biomass of the anchovy in the Bay of Biscay within the National Sampling Plan.

Annually, the European Union develops two research campaigns in the area of ​​NAFO (North Atlantic Fisheries Organization), one in the 3NO division and another in the 3M and 3L (Flemish Cap Series). This campaign is part of a historical series in order to provide indices for the evaluation of the stock of halibut and other groundfish species in the area such as flounder, redfish, grenadier, cod or shrimp. The Flemish Cap bank is an isolated bank of the American coastal platform with an area greater than 10,000 square miles and is located outside of the Exclusive Economic Zone of Canada. The exploitation of the resources of this area is regulated by the international agreements of NAFO. GOALS Estimation of abundance and biomass indices of the target species, as well as the study and analysis of the demographic structure of their populations and the oceanographic conditions in the Bank.

Annually, the European Union develops two research campaigns in the area of ​​NAFO (North Atlantic Fisheries Organization), one in the 3NO division and another in the 3M and 3L (Flemish Cap Series). This campaign is part of a historical series in order to provide indices for the evaluation of the stock of halibut and other groundfish species in the area such as flounder, redfish, grenadier, cod or shrimp. The Flemish Cap bank is an isolated bank of the American coastal platform with an area greater than 10,000 square miles and is located outside of the Exclusive Economic Zone of Canada. The exploitation of the resources of this area is regulated by the international agreements of NAFO. GOALS Estimation of abundance and biomass indices of the target species, as well as the study and analysis of the demographic structure of their populations and the oceanographic conditions in the Bank.

This survey covers the international NAFO Regulation Area in divisions 3NO. It started in 1995 with the only purpose of collecting data for stock assessment of target species down to 700 m, but its aims and research area have widened with time. Currrently, the survey covers a depth range of 50-1500 m and its goals are the following: 1. Regarding the target species (Hippoglossoides platessoides, Limanda ferruginea, Reinhardtius hippoglossoides, Glyptocephalus cynoglossus, Gadus morhua, Sebastes sp, Macrourus berglax, Centroscyllium fabricii and Raja radiata) and other species of commercial interest (Urophycis tenuis; Pandalus borealis) : a. to obtain biomass and abundance indexes, b. to estimate recruitment, c. to investigate the population structure To achieve this, biological information (length, weight, sex, maturity, stomach contents) is obtained from about 30 species, as well as otoliths and gonads from cod, Greenland halibut and roughead grenadier. The remaining fish and commercial invertebrate species are length measured and weighted. 2. Collection of oceanographic data (temperature, salinity, oxygen and fluorescence); 3. Invertebrate data collection: all species are identified to the maximum possible level on board, or otherwise photographed and preserved for later examination at the lab, counted and weighted, with the aim of investigating the benthic invertebrate faunal assemblage and presence of vulnerable species

Annually, the European Union develops two research campaigns in the area of ¿¿NAFO (North Atlantic Fisheries Organization), one in the 3NO division and another in the 3M and 3L (Flemish Cap Series). This campaign is part of a historical series in order to provide indices for the evaluation of the stock of halibut and other groundfish species in the area such as flounder, redfish, grenadier, cod or shrimp. The Flemish Cap bank is an isolated bank of the American coastal platform with an area greater than 10,000 square miles and is located outside of the Exclusive Economic Zone of Canada. The exploitation of the resources of this area is regulated by the international agreements of NAFO. GOALS Estimation of abundance and biomass indices of the target species, as well as the study and analysis of the demographic structure of their populations and the oceanographic conditions in the Bank.

Annually, the European Union develops two research campaigns in the area of ¿¿NAFO (North Atlantic Fisheries Organization), one in the 3NO division and another in the 3M and 3L (Flemish Cap Series). This campaign is part of a historical series in order to provide indices for the evaluation of the stock of halibut and other groundfish species in the area such as flounder, redfish, grenadier, cod or shrimp. The Flemish Cap bank is an isolated bank of the American coastal platform with an area greater than 10,000 square miles and is located outside of the Exclusive Economic Zone of Canada. The exploitation of the resources of this area is regulated by the international agreements of NAFO. GOALS Estimation of abundance and biomass indices of the target species, as well as the study and analysis of the demographic structure of their populations and the oceanographic conditions in the Bank.