Recruitment and feeding of juvenile leaping grey mullet, Liza saliens (Risso, 1810) in the Neretva River estuary (south-eastern Adriatic, Croatia)

摘要

The recruitment of leaping grey mullet, Liza saliens juveniles in the Neretva River estuary (middle eastern Adriatic Sea, Croatia) started in July, was highest in August, decreased in September, and was unobserved later. The juveniles firstly occupied mouths of rivers and channels and then started migrating to more freshwater habitats. By feeding investigation, the harpacticoid copepods were the dominant prey in the stomachs of L. saliens juveniles during the period from August to December and nematodes replaced those as the dominant prey from January to April. Plant material in the stomachs started to appear at 24 mm of standard length, and was common prey in fish larger than 26 mm. In comparison with other Adriatic mullet's species, the leaping grey mullet juveniles first started to recruit during July and August, while other grey mullet species appeared later (in September) in the Neretva River estuary. Such intraspecies spawning and recruitment segregation together with the optimal quantity and quality of available and preferable prey could provide an explanation for the recent success and propagation of this species in this area.