For the first time this year, the research team of the Brazil Dusky Grouper Project (PMB) recorded a reproductive aggregation of groupers in São Francisco do Sul, Santa Catarina. The visual census, in which divers make the underwater count of these fish, spotted 38 specimens of the species, something currently considered rare on the Brazilian coast. a critically endangered species.
The general manager of the project, Maíra Borgonha, stressed that this “is a rare event, which happens on a few moons of the year, in few places on the Brazilian coast”.
The project’s researcher, Leonardo Bueno, a doctor in environmental oceanography, says that seeing and monitoring aggregations with dozens of groupers in Brazil is essential for the species’ recovery work. However, in an interview with the Brazil Agencythat the current numbers are very low when compared to past decades of the 1960s, 1970s, 1980s. “We do a work called ecological knowledge, interviews with former fishermen and the reports reached hundreds of groupers, including the captures reached dozens” , said Bueno.
Brazil Meros Project – Athila Bertoncini Andrade
Created in 2002 by a group of researchers from Santa Catarina, the project operates in nine states along the Brazilian coast – Pará, Pernambuco, Alagoas, Bahia, Espírito Santo, Rio de Janeiro, São Paulo, Paraná and Santa Catarina – and aims to guarantee the conservation of marine ecosystems and the grouper (Epinephelus itajara), considered the largest species of grouper in the Atlantic Ocean.
In the last 65 years, groupers have experienced a significant population decline, estimated at over 80%.
threat of extinction
Due to the destruction of their habitats, overfishing and pollution, since 2006 the grouper has been considered an endangered species and has been fully protected for almost 20 years, with its capture, processing, transport or commercialization considered practices prohibited throughout the national territory. As of 2006, the project was sponsored by Petrobras, through the Petrobras Socio-environmental Program.
This was the second largest shoal recorded by the project since monitoring the species began in 2002. In February 2012, the team spotted between 45 and 50 fish in the same location. Other expressive numbers of groupers gathered were only recorded by the PMB in seizures, such as the one made in 2006, in Maranhão, and in the summer of 2021, in the state of Pará, registering more than 40 copies of groupers caught illegally. According to the researchers, these irregular fisheries must have taken place on top of the aggregates, which represent the only chance for the species to reproduce during the year.
past decades
In addition to overfishing, pollution, especially within the estuaries, has led to a decrease in groupers in the country. This type of fish has a life cycle in which it does reproductive aggregation. The larvae or eggs of the individuals are carried by the currents and enter bays, estuary areas, causing the young, called juveniles, to grow in the mangroves.
“The devastation of mangrove environments for the construction of ports and houses, for example, also influences the reproduction of groupers. They need that environment for the larva to develop and the juvenile to grow there. Pollution in these places has a major impact on grouper populations,” explained Leonardo Bueno.
Some studies show that large grouper females, or large matrices, which reached between two and 2.5 meters, considered the best reproducers of the species to generate stronger groupers, were the main targets of predatory fishing, which also contributed to species reduction.
The researcher informed that the grouper has a very long life cycle, reaching up to 40 years. It takes six to eight years to start breeding. “At this point, it will already be a fish weighing around 40 kilos, measuring one meter in length. It is when it leaves the estuary waters and starts to inhabit the open sea areas, the reefs”. The grouper has a generational lifespan of about 21 years. This means that a new generation of groupers appears every 21 years.
Brazil Meros Project – Athila Bertoncini Andrade
The grouper images were recorded during the dive to maintain the acoustic telemetry network, monitored by the PMB. Telemetry is present in the states of Santa Catarina, Paraná and São Paulo. It is a research component used to study the movement patterns of groupers, the use and occupation of aggregation areas. The data obtained from this monitoring are important, since preserving the breeding areas is considered a key factor for the conservation of the species. The diving operation was supported by the team from Transpetro, a Petrobras subsidiary, at the São Francisco do Sul Terminal.
reproductive shoals
Also known as Senhor das Pedras, the grouper belongs to the grouper family, alongside the grouper and grouper, among other fish, and usually aggregates in reefs in the open sea, especially rocky reefs and artificial reefs that contain large holes, caves and high relief. , which are more protected areas that offer greater shelter, security and food.
Grouper reproductive aggregations occur annually each summer from December to March. During the aggregation season, shoals are usually four times larger than in non-reproductive periods. According to the researchers, these encounters represent the only chance of reproduction of the species in the year, although they constitute, unfortunately, an extremely attractive opportunity for irregular fishing. Because they are extremely docile and large, reaching 2.5 meters in length and weighing over 400 kilos, groupers become easy prey for irregular fishermen. In the samples taken by the PMB, the largest grouper recorded was 2.15 meters long.
In addition to protecting the grouper, the PMB aims to make the population aware of the conservation of the species and the environment. “We seek to bring this information to children, adults, fishermen, about how long they live, the importance that groupers have, so that they start to protect, not fish anymore. With awareness, we end up reducing illegal fishing on the species, taking information to the population”, emphasized Bueno.
