Artificial reefs have been used in many countries to increase coastal fishery productivity. In order to increase fish attraction to the Northern Coast of Rio de Janeiro State, it was installed an artificial reef (1,500 m²) 5 nautical miles off Manguinhos's Bay (São Francisco de ltabapoana, Rio de Janeiro). The artificial structures were made of tires, concrete and cement blocks. A gill net of 125 x 3 m was monthly used in the artificial reef (AR) and in a control area (CA) to determine the effect of the experimental structures on the stock and diversity of coastal sharks. Considering the complexity of a sustainable elasmobranch exploitation, sharks were focused in this study. During 24 months of investigation (April/96 to March/98), a total of 325 individuais distributed in four shark species were captured in the two areas (AR and CA): Mustelus higmani (Springer & Lowe, 1963) (AR = 70; CA = 82 individuals), Rhizoprionodon lalandii (Valenciennes, 1839) (AR = 86; CA = 56 individuals), R. porosus (Poey, 1861) (AR = 16; CA = 14 individuals) and Carcharhinus brachyurus (Günther, 1870) (AR = 1 individual). The attractive potential of the artificial reef is suggested by the predominance of the shark R. lalandii in the reef complex after the first year of monitoring, with the increase of the structures.
Artificial reefs; coastal sharks; Rio de Janeiro State Northern Coast