Stock identification of tainha (Mugil liza) by analyzing stable carbon and oxygen isotopes in otoliths

Abstract

We investigated the use of 13 C and 18 O stable isotopes in otoliths of juvenile tainha (Mugil liza) as indicators of the stock structure of this species of mullet in the southern Atlantic Ocean. Our analysis identified 2 different spawning stocks along the Brazilian coast: the southern stock, from So Paulo (25S) to Chui (33S), with distinct seawater temperature requirements for spawning (18-21C), and the northern stock, from Rio de Janeiro (23S) to the north (up to 19S), spawning in seawater temperatures of 21-24C. These results will contribute to the development of appropriate stock management measures.