Large schools of tilapia and catfish appear in Campos canal, raising health concerns

Hundreds of tilapia and African catfish have recently appeared in the Campos-Macaé Canal, specifically in the Beira-Valão section in Campos dos Goytacazes, Northern Fluminense. This unusual concentration of fish has attracted local residents, some of whom are interested in catching them for consumption. However, experts strongly advise against consuming these fish due to significant health risks. The phenomenon has prompted questions among residents about the reasons behind the fish aggregation in this particular canal stretch. Professor Manuel Vazquez Vidal Júnior from the State University of Northern Fluminense (Uenf) explained that tilapia's adaptability, including their parental care and resilience, contributes to their survival and reproduction even in suboptimal environments, further aided by people feeding them. The African catfish also exhibits high adaptability, possessing an auxiliary respiratory organ that allows it to breathe atmospheric oxygen, enabling survival in degraded conditions. Despite the ease of capture and abundance, specialists urge caution. Vidal Júnior highlighted that the Campos-Macaé Canal receives urban drainage water and may be affected by illegal sewage connections. During rainy periods, street debris and pollutants are washed into the canal, introducing heavy metals, tire particles, and other residues. These contaminants are absorbed by the fish, making them unsafe for consumption. Fish from contaminated environments can accumulate pathogenic microorganisms and harmful substances, posing risks to human health. The Campos-Macaé Canal, a historic 109-kilometer waterway built during the imperial period connecting Campos dos Goytacazes and Macaé, has historically faced sanitation and environmental challenges. The recent appearance of the large fish schools has renewed public attention to these issues, with experts reiterating that the fish's presence does not indicate their suitability for food.