IDADE E CRESCIMENTO DE PEIXES DE RIACHO: MÉTODOS E DESAFIOS PARA A OBTENÇÃO DE ESTIMATIVAS ROBUSTAS

Abstract

Age and growth are key elements on the fish population dynamics, allowing the age structure identification, age of first maturity, mortality rates and longevity calculations, among others. There are also age-based fisheries and ecological models that depends on these studies. It is a challenger field due to the intrinsic variability of growth process at individual and population levels, influenced by endogen and exogen factors. For freshwater fishes, the modal progression analysis, and the analysis of growth rings on scales are widespread applied for age and growth. Like all methods, premises and limitations exist and they must be observed. Otolith analysis is more accurate, unless difficult to stream fishes due to sample size requirements, small otolith size and rings record, specially at the Neotropical region. In this study, sample techniques, material and data acquirement and analyses are presented, focusing stream fishes. Limitations were identified in the results available in the scientific literature due to no consideration of methods premises allied to the mechanic use of software and manuals. For further studies, length frequency analysis, otolith daily rings and experiments are recommended to estimate age and growth of fishes from brooks and streams.