Distribution of black hakes Merluccius senegalensis and Merluccius polli along the Moroccan Atlantic coast

In the Northwestern coast of Africa three species of hakes overlap. These include European hake Merluccius merluccius (Linnaeus, 1758), Senegalese hake Merluccius senegalensis Cadenat, 1950 and Benguela hake Merluccius polli Cadenat, 1950. The Black hakes M. senegalensis and M. polli have their northern distribution limit in Morocco. In this study, this limit was set to 33.05°N (33° 3' 0" N) for M. senegalensis and 28.28°N (28° 16' 48") for M. polli. The fluctuation in the northern limit of the black hakes distribution could be a result of changes in oceanographic parameters (as the area is affected by the upwelling and considered as a transition zone between a warm and a cold region) or a seasonal migration of the species. A misidentification of species is not excluded. The general trend of the yield’s average decreases with latitude. South of the latitude 25°N M. polli is more abundant in average than M. senegalensis even if the latter could show some high yield spots (up to 155 kg h-1 ). North of the latitude 25°N, the situation is inversed. Black hakes were caught up to about 1000 m depth (1055 m for M. senegalensis, deeper than the ever-reported depth). M. polli showed a deeper distribution than M. senegalensis and was absent from the strata shallower than 300 m. The main concentration of M. polli was between 500 and 700 m where 81% of individuals are caught. The main concentration of M. senegalensis was in the stratum 300-600 m where 77% of individuals are caught. The maximum overlap of the two black hakes species was between 400 and 600 m suggesting a deeper population in the northern zone of the distribution of these species. Although M. senegalensis shows a maximum size (73 cm) greater than M. polli’s maximum size (66 cm), its average size in the study area (44.06 cm) was significantly smaller than M. polli’s average size (48.84 cm). The black hakes are considered as shared resources and need more studies with a regional scope so as to contribute to their management