The Piracema is the movement of schools of fish that swim upstream against the current, during the breeding period, to spawn. The word originates in the Tupi language, which means “output of fish”, “movement to go up” (pira means fish, while cema means ascent). In most of Brazil, the piracema coincides with the period of summer rains, lasting about 4 months, in most states between November and February. In the southern states, it starts in October and ends in January. In Roraima it is different, it takes place between March and June.
Before the phenomenon, nature already sends signals, which are perceived by the fish, that the favorable season for reproduction is approaching. Warmer days, frequent rains and more oxygenated water make millions of fish, male and female, dispersed in the rivers group together in large shoals, preparing for the ascent. The piracema fish, also known as migrators, need to make an intense physical effort to go up to the river. This increases hormone production and fat burning, improving the reproductive process. However, during this period they also become easy prey, due to physical fatigue.
During fish reproduction, commercial fishing is restricted, so federal and state governments institute a closed season for rivers and inland waters during the piracema. The ”Período do Defeso” is one of the measures created along with the Fishing Code, developed by the Brazilian government in 1967, aiming to guarantee the protection of the species' reproduction periods. At this time you cannot fish with a gillnet, for example, because it is a non-selective equipment. Only subsistence fishing by communities is allowed, even so there is a daily limit that must be respected, so that an imbalance does not arise.
Human actions and interventions, in addition to criminal fishing, can interfere in the reproductive process of these animals. The environmental impact of dams, for example, is gigantic, as they annihilate the natural cycle of reproduction of several species of fish that migrate during the piracema. The dams are major obstacles in the river, as most adult fish cannot climb to get back to the headwaters, even with the supposed "water stairs" on the side of these buildings. If they are an insurmountable obstacle for adults, they are also a problem for the young, who are left in an unprotected situation and die before reaching the floodplains.
The “Período do Defeso” allows the species to reproduce in a satisfactory volume so that their subsequent fishing is not predatory and causes their extinction. Therefore, this is the period that guarantees the sustainability of the practice of fishing, in the midst of so many human actions that interfere in the reproductive cycle of these animals. This is a crucial moment for the survival of the species and, therefore, it is essential that fishing be restricted to areas defined by IBAMA and the Secretary of the Environment, accompanied by actions to raise awareness about the conservation of endangered species.
REFERENCES
1. FISH TV. Brasilienses - As ameaças ao dourado na bacia do Rio Uruguai. Youtube, 2021. Disponível em: . Acesso em: 2 de abril de 2022.
2. O que é a piracema? SUPER Interessante, 2018. Disponível em: . Acesso em: 5 de abril de 2022.
3. PIRACEMA. Instituto Estadual de Florestas. Disponível em: . Acesso em 5 de abril de 2022.