Age and growth of mapará (Hypophthalmus marginatus) in the Central Amazon

Abstract

The present work seeks to contribute for the conservation and management of the mapará(Hypophthalmus marginatus), an important export fishing resource of Amazonas for which is necessary to know essential information of its population dynamics. To contribute to this purpose, the present work established as objective to identify a structure for reading of age rings, to determine the parameters of growth of the mapará (H. marginatus), Central Amazon, Amazonas - Brazil. The work was made through the otoliths analysis collected in the period of December of 1996 to August of 1997. The otolith chosen for reading was the asteriscus, being the reading made in a stereomicroscope with coupled monitor. The mark structures were validated by means of the analysis of the relative marginal increment, being found two rings. The values estimated for the parameters in the period were L <FONT FACE=Symbol>¥</FONT> = 52,63 cm; k = 0,555 year; to = -0,029 and M = 0,552. The hydrologic cycle and reproductive behavior were the responsible factors for age rings.

Age; growth; Hypophthalmidae; Amazon