ABSTRACT
Another kind of brackish waters are lagoons where salinity are subject to strong alteration during seasons. In the Lagoon Maugio at the French Mediterranean coast the salinity varies between 10 and 37 ‰. Gobius niger consumes there predominantly fishes but also larger crustaceans and some algae, totally 16 components (Joyeux et al., 1991). Th ese food items represent the genuine lagoon organisms. In a Corsican lagoon with salinities between 9 and 50 ‰, Pomatoschistus microps feeds almost exclusively on harpacticoids, whereas in other lagoons Gobius niger, G. paganellus, Zosterisessor ophiocephalus and Pomatoschistus marmoratus include a broader food spectrum with a preference of diverse amphipods and chironomid larvae (Casabianca and Kiener, 1969). Th e infl uence of salinity on the species richness is therefore mirrored by the food of predators, referred to a lesser level also by the group of gobies. Th ey can thus confi rm the rules of Th ienemann (1939) for extreme habitats and of Remane (1958) especially for brackish waters.
