Tambaqui is 'smaller and rarer'; understand what put it on the endangered species list

For tambaqui, the results indicated a reduction of approximately 50% in both the body size of the fish and the catch rate per unit of effort in the most affected regions. The work used information from fishermen in rural communities to reconstruct how the pressure exerted by a large city can affect animal populations far beyond its urban limits. Reducing the size of specimens is especially important because the tambaqui is a relatively slow-growing fish until it reaches the reproductive stage. Studies cited in research on the species indicate that females reach sexual maturity, on average, when they are between 50 and 55 centimeters in length and around three years of age. The recurring capture of smaller animals can cause part of the population to be removed from rivers before reproducing. Historically, the size of fish landed in the main Amazonian markets had already raised concern among researchers, with juveniles representing an important portion of catches. The fish that helps supply Manaus The pressure on natural stocks did not start now. Studies on the history of tambaqui exploitation show that the species was once among the most important fishing resources in the Amazon region. Tambaqui faces challenges in nature eulucasramus / iNaturalist Data recovered by researchers show that, in 1976, around 16 thousand tons of tambaqui arrived at the port of Manaus. At the end of the 1990s, this landing had fallen to less than 4 thousand tons, despite the city's population growth in the meantime. The trend has led researchers to associate the reduction in stocks mainly with overfishing, especially the removal of juveniles and large breeding specimens. The concern also appears in genetics. In a study published in 2018 in the journal Frontiers in Genetics, researchers analyzed natural tambaqui populations from 21 locations in the Amazon basin, in addition to one location in the Bolivian sub-basin. 539 individuals were analyzed by mitochondrial DNA markers and 604 by microsatellites. The results showed genetic differences between certain populations and signs of population reduction over time. The authors advocated that conservation strategies consider these differences between populations and reduce the effects of overfishing on natural stocks. Tambaqui important for the forest The loss of tambaquis does not only have consequences for fishing. The species also plays an ecological role in the flooded forest areas of the Amazon. During the flood season, tambaquis enter the floodplains and flooded forests to feed. Fruits and seeds are part of the diet, and the fish acts as a disperser of seeds from Amazonian trees and shrubs. Tambaqui is 'smaller' and rarer; understand why abraao_arthur_253 / iNaturalist This relationship means that the decrease in large individuals can have repercussions that go beyond the fish population itself. The life cycle of the tambaqui is directly associated with the dynamics of Amazon floods. During the breeding season, eggs and larvae can be transported by water to floodplain environments, while adults travel through rivers and flooded areas for reproduction and feeding. Will fishing be prohibited? The inclusion on the list of threatened species had an immediate consequence for the discussion about the future of fishing. In addition to Ordinance No. 1,667, the Ministry of the Environment published Ordinance No. 1,666/2026, which establishes rules for the exploitation of fish and aquatic invertebrates classified as threatened. In July, a new standard, Ordinance GM/MMA No. 1,748/2026, created a transition period for tambaqui and peroá (Balistes capriscus), another species that joined the list. In the case of these two species, the restrictions provided for by legislation come into effect after 120 days, while the government works on defining specific management instruments.