Print version ISSN 1679-6225
NOBREGA, Marcelo Francisco de and LESSA, Rosangela Paula. Age and growth of Spanish mackerel (Scomberomorus brasiliensis) off the northeastern coast of Brazil. Neotrop. ichthyol. [online]. 2009, vol.7, n.4, pp. 667-676. ISSN 1679-6225. http://dx.doi.org/10.1590/S1679-62252009000400016.
Age and growth of the Spanish mackerel (Scomberomorus brasiliensis) caught off northeastern Brazil were determined. A total of 831 otoliths were examined - 296 from males (12 - 75 cm FL), 212 from females (11.5 - 72 cm FL) and 323 from specimens of undetermined sex (12.4 - 75 cm FL). There was a high percentage of juveniles in the catches, resulting mainly from the use of gillnets. Marginal increment analysis of the otoliths indicated that the shortest distances from the last ring to the edge occurred from November to May, laying down just one ring annually. One to eight rings were found, with specimen lengths ranging from 11.5 to 75.8 cm. The Schunute model was used to determine what model was best fit the data, demonstrating that the specialized von Bertalanffy growth equation is the most appropriate. Curves were established for males (L∞ = 79.52 cm, K = 0.189, t0 = -0.384 year) and females (L∞ = 109.18 cm, K = 0.114, t0 = -0.414 year), which resulted in distinct growth patterns between sexes. Based on the parameters estimated for the sexes separately, males have an approximate longevity of 15.5 years, whereas female longevity is 25.9 years. Specimens between 2 and 6 years of age represented 86% (n = 5,290) of the catch composition, characterizing the species as a catchable stock in the region. The present study updates essential information for assessing the stock of this important resource, for which the last growth studies in the region were carried out approximately thirty years ago.
Keywords : Otoliths; Scombridae; Neritic species.