Arapaima

The arapaima, also known as pirarucu or paiche, is a captivating giant among freshwater fish, native to the Amazon and Essequibo basins of South America. Belonging to the genus Arapaima, these fish can grow up to an impressive 3 meters in length, making them one of the largest freshwater fish in the world. Unfortunately, their populations have dwindled in their native habitats due to overfishing and habitat destruction. To complicate matters, they have been introduced to other tropical regions where they sometimes become invasive.

There are several species within the Arapaima genus, including Arapaima arapaima, Arapaima agassizii, Arapaima gigas, Arapaima leptosoma, and Arapaima mapae. Because these fish do not migrate and are widely spread out, scientists believe there might still be undiscovered species in the Amazon Basin.

Arapaimas are easily recognizable by their torpedo-shaped bodies, large blackish-green scales, and striking red markings. They possess a specialized respiratory system that allows them to breathe air in addition to using their gills. Their scales are remarkably tough, featuring a hard outer layer and strong internal collagen fibers for added protection.

These fish have a diverse diet, consuming fish, crustaceans, fruits, seeds, and even small terrestrial animals. As air breathers, they can survive in environments with low oxygen levels. As top predators in their ecosystems, particularly in oxbow lakes, arapaimas play a crucial role in maintaining the balance of prey populations.

Regarding reproduction, arapaimas lay their eggs during the low-water season. The male then takes on the role of mouthbrooder, safeguarding the young in his mouth until they are ready to venture out on their own. During breeding, females have been observed secreting a substance that the young feed on, showcasing some unique parental behaviors.

Arapaimas have a long-standing relationship with humans. They are highly valued for their meat, which is harvested using traditional methods like harpooning and clubbing. Besides being a food source, arapaimas are utilized in various industries and have medicinal applications. They are also popular in aquaculture, where farm-raised arapaimas serve as an alternative to other fish species.

Due to the threat of overfishing and their declining populations, various conservation efforts have been initiated. These include fishing bans, sustainable management strategies, and monitoring programs to safeguard arapaima populations. Despite these measures, the current status of arapaima populations in the Amazon River Basin remains uncertain, leading to their classification as "data deficient" on the IUCN Red List.