Larviculture of the Zungaro jahu (Ihering, 1898)- JAÚ, an endangered species under laboratory conditions

Abstract

Zungaro jahu (Ihering, 1898) is a fish threatened with extinction, according to the Red List of the Ministry of the Environment and Legal Amazon. The objective of this work was to propose a cultivation protocol for the jaú. In the laboratory, 54 larvae were cultured for 15 days. Six specimens of jaú were removed, with a survival rate of 11%. The estimated cost of the experimental unit was USD 62.50. With improvement of the cultivation system, we could achieve survival of 9 fingerlings, one for each experimental unit, at an average cost of $ 1.78 per fingerling. The authors believe that the cultivation of the jaú can be overcome, and they raise some hypotheses to justify the extinction in natural environments. Possible causes include changes in natural systems such as climate change, fishing, predation of juveniles by introduced species, diseases introduced, changes in food chains, limitation or restriction of habitat area, physical changes in the environment (formation of lakes for electricity generation), eutrophication or pollution from different sources. The development of larviculture protocols for this species would be an important tool to prevent the extinction, enabling at least its cultivation in the laboratory.