Bentes, L. Age and growth, reproduction and feeding ecology of Mullus surmuletus L. 1758, red mullet, from the Southwest coast of Portugal.

Growth, feeding ecology and reproduction of red mullet (Mullus surmuletus) from the south-west coast of Portugal were studied. Growth was studied by means of length frequency analysis, and age-length keys were constructed from fish which were aged by reading growth rings on otoliths and scales. Linear and non-linear fitting methods were used to estimate parameters of the von Bertalanffy growth curve from mean lengths-at-age. The best parameter estimates were obtained for scale data and non-linear least-squares fitting: L¥ = 31.5, K = 0.429, and t0 = -0.00157.

Separate analyses for males and females showed that females grew faster. Stomach content analysis, diet indices, the feeding coefficient, and the index of relative importance suggest that the diet of the red mullet consists primarily of prey from the Phyla Arthropoda and Annelida, with the Phylum Echinodermata being of lesser importance. In terms of feeding ecology the red mullet is an opportunist, with the type of substrate being of primary importance in determining the diet. The spawning period extends from April to June, with females dominating the samples during the spawning months while males were more common during the resting period.