Patrols from the Servicio Nacional de Guardacostas captured 10 fishermen and three boats over the weekend as officials enforced the moratorium in the Gulf of Nicoya.
The moratorium is to allow marine species to recover, and the government provides payments to those who are prohibited from fishing.
Nevertheless, the coast guard said its crews were able to find illegal nets and traps in the gulf.
The coast guard said that more than 100 wire fish traps were located and hundreds of fish were liberated.
El Instituto Mixto de Ayuda Social and the Instituto Costarricense de Pesca are supposed to be providing economic aid to fishing families while the moratorium continues.