The gerival is one of the main types of fishing gear used to catch shrimp in the Baía da Babitonga Bay, on the North coast of the State of Santa Catarina. This gear was initially used only with rowing boats, but the use of motorized boats was introduced recently, raising some issues concerning the changes on the fishery system (e.g. catch composition, fishermem efficiency). The aim of this paper is to characterize, by means of on-board observations, the operational pattern of gerival fishing in São Fransisco do Sul carried out by motorized boats and to compare the shrimp and by-catch captures to fishing outcomes of non-motorized boats. The results indicated that the use of motorized boats did not result in higher shrimp yields, or in larger by-catch captures. Nevertheless, the use of motorized boats enable great mobility between fishing grounds and also enable a more rapid return to the initial towing point.