Otolith micro- and macrostructure analysis to improve accuracy of growth parameter estimation for white mullet Mugil curema

Aquatic Biology

Eric Morize¹  Rosangela Lessa¹  Francisco M. Santana¹  Jacques Clavier¹ 

关键词: Mugil curema;    Otoliths;    Age and growth;    White mullet;   

DOI  :  10.3354/ab00189

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: Age and growth studies on the white mullet Mugil curema present (Valenciennes, 1836) dissimilarities with regard to the parameters estimated. It is therefore necessary to undertake a growth analysis based on micro- and macrostructures of otoliths from the species in order to reveal the cause of such dissimilarities. Microstructures were validated through otolith marking by balneation in alizarine complexone and demonstrated daily periodicity. Daily microstructures were observed in individuals up to 15.7 cm in fork length and exhibited 5 distinct growth zones. Zones I, II and III (62 d) composed the first macrostructure and Zone IV (223 d) composed the second. It was not possible to see microstructures in Zone V and, beginning with this zone, macrostructures were considered annual, based on the analysis of mean monthly marginal increments. Using daily microstructures and annual macrostructures, the von Bertalanffy function provided the following parameters: L_∞ = 34.4 cm, K = 0.365 and t₀ = 0.311 yr. The following factors caused the dissimilarities between curves for white mullet: (1) absence of samples for ages 0⁺ and 1 yr, which caused a high value of mean lengths for these age classes and a diminished K-value; (2) the tendency toward overestimation at the age of 1 yr when estimated from macrostructures; (3) identification of the first 2 macrostructures as annual; and (4) absence of young-of-the-year specimens, causing t₀ to be significantly different from 0. These factors lead to the underestimation of the parameters, which makes growth estimates imprecise.

【 授权许可】

Unknown