Biología reproductiva del bagre cominate Occidentarius platypogon (Pisces: Ariidae) en el sureste del golfo de California

Abstract

The cominate sea catfish from the southeastern Gulf of California is an important species that is commercially exploited. However, studies on biology of this species are scarce; therefore, harvest regulations do not exist for this species in Mexico. The aim of this work was to describe reproductive biology of Occidentarius platypogon. Gillnet samples were carried out from October 2008 to December 2009. In total, 480 fish were dissected; gender sex and gonad maturity stage were determined macroscopically. Results indicated that the spawning season runs from May to August and generally with synchronic gonad development. Fecundity of the chihuil sea catfish was 37, which is low because this species shows parental care via oral incubation of fry, reducing mortality. Estimated length at first maturity is 37.6 cm total length (TL). Average length at first catch from the artisanal gillnet fishery is 23.4 cm TL, indicating that this fishery is harvesting fish that have yet to have had a single reproductive event. A large number of captured fish consisted of males that were incubating fry; thus, likely causing large fry mortality.