Population parameters of main fishery resources in the basin of the Apure River, Venezuela (2000-2003)

Abstract

Population parameters, performance index (∅) and exploitation rates (E = F/Z), of the 14 most important commercial fish species, in the Apure River, were estimated from length frequency distributions of commercial catches in the period 2000-2003. Growth parameters were used to determine the status of the principal fisheries resources of the Apure River. The analyzed species represented 83% of the total commercial species. The results showed a predominance of values relativity low of K and high L∞, common in longevity species. This data combined with the high values from estimations of Z and F showed a survival annual high rate and low stock tuner-over rate. The E estimations for the 14 fish species were high. E0,1 (0.50- 0.94). The overfishing indicators to four most fish species abundant (P. mariae, P. tigrinum, M. duriventre y H. littorale), showed that at least three species were heavy exploited. In general the analysis indicate that these 14 fish species have been strongly fished, and the data obtained is a starting point (as biological reference point) to be used for the assessment and management of fisheries resources in the Apure River.