Characterization of spawning rhythms of a sparidae aquaculture species, the white seabream (Diplodus sargus), in the south of Portugal

One of the most visible features of fish reproduction is seasonality; however, daily rhythmicity is present in most species and should not be disregarded. This study investigated the seasonal and daily spawning rhythms of the white seabream (Diplodus sargus) in captivity, and a possible endogenous control of the daily rhythm. Spawns were monitored daily, during an entire reproductive season by using an automatic and programmable egg collector. The spawning season lasted 5 months, from January until June, when temperatures oscillated between 11.5 and 24.4°C. Female fecundity was higher between 17.5 and 20.4°C, suggesting a temperature influence in spawning. This species showed a very clear daily spawning rhythm (Cosinor analysis, p