Zonas y épocas de reproducción del atún aleta amarilla Thunnus albacares (Bonnaterre, 1788) en el Pacífico Mexicano

Abstract

In order to contribute to the knowledge of the reproductive behavior of yellowfln tuna Thunnus albacares in the Mexican Pacific, the female gonadal development was analyzed on the basis of samples taken from commercial catches made by the mexican tuna fleet from January 1984 to January 1986. It is concluded that yellowfin tuna can reproduce in this area from March to November; in April-May and October-November a higher reproductive activity was detected. The minimal spawning furcal length was found to be 70 cm; however 50% of the females area able to spawn when they reach 105 cm. Taking into account the results capture lenght composition by areas and the values of the gonadal index used,the neritic zone off Southern Mexico, the Revillgigedo Islands and the entrance to the Gulf of California, are defined in order of relative importance, as reproductive areas.