Population structure of the black arowana (Osteoglossum ferreirai) in Brazil and Colombia: implications for its management

In regions with high biodiversity, where species are exploited as a source of income, it is essential to learn more about the species that are being commercialized. For the ornamental fish black arowana (Osteoglossum ferreirai), distributed only in Colombia and Brazil, there is currently a lack of information about population estimates in each location, genetic data and lastly, about the events that lead to the current distribution of the species. A genetic population study was conducted by sequencing the mitochondrial genes cytochrome b and ATPase 6, and genotyping of eight microsatellite loci. Mitochondrial gene results indicated the absence of variable sites, and the microsatellite results showed a significantly lower heterozygosity than expected demonstrating that currently the genetic diversity of the species is low. The fact that this species is been exploited and that it shows low genetic diversity means it can quickly become endangered. For this reason, conservation, management and use programs for the black arowana should include and consider the genetic data obtained as well as additional life history and ecological factors to promote its sustainable use.