Stock assessment and population parameters for Triportheus spp. and Pellona flavipinnis in floodplain lakes, central of Amazon, Brazil

Abstract

It is essential to provide data on fish stocks, especially those that appeared more recently on fishing landings. The present study estimated growth, mortality and evaluated the fish stock of Triportheus albus, Triportheus angulatus, Triportheus auratus, and Pellona flavipinnis in floodplain lakes in central Amazon, Manaus (AM), Brazil. Samplings were carried out monthly between 2006 and 2007 and bimonthly until 2008 using gillnets. We evaluated the growth parameters (L∞, k, t0, t_achor, Ø, A0.95), natural, total, and fishing mortality, exploitation rate, and yield per recruit. The results showed T. auratus had the lowest estimated current fishing mortality pressure, while T. angulatus and T. albus had the highest fishing mortality pressure. It indicates that T. angulatus and T. albus are heavily exploited commercially. Considering current fishing mortality, T. angulatus and T. albus presented values above the maximum sustainable yield, indicating that these species are being exploited in an unsustainable way. This was the first time these fisheries stocks were evaluated. Despite the data being from a few years ago, these values are the only available and may be the baseline for the fisheries management plans.