Juvenile and adult food habits of Archosargus probatocephalus (Teleostei: Sparidae) in a tropical estuary of Veracruz

Abstract

Juvenile and adult food habits of A. probatocephalus were analysed during one annual cycle, sampling bimonthly over 24 h cycles, in two habitat types (with and without submerged vegetation) in the Pueblo Viejo lagoon. The species showed an omnivorous diet, feeding mainly on invertebrates (mostly peracarids) and plants (?80%), with detritus (?20%) as a secondary choice. Juvenile (small individuals) tended to consume more small invertebrates (>57%), while adult individuals (larger ones) fed mainly on plants (>40%). Some of these changes were associated with an increase in the intestine relative length as fish grew up. In the seagrass habitat and during the dry season predominated juvenile individuals, which showed a larger invertebrate consumption (mainly copepods and peracarids), whereas in the habitat without vegetation and during the rainy season, adult individuals were more common, consuming mainly detritus and plant items. Although diet was similar between day and night, feeding intensity was greater during daylight hours (P=0.041), suggesting a diurnal predator condition in this species. In this way, the life history of the species at Pueblo Viejo lagoon shows adaptations towards maximizing the use of trophic resources, according to its seasonal and spatial availability.