|Changes in predation by the juvenile goby Deltentosteus quadrimaculatus (Teleostei, Gobiidae)|
Villiers, L. (1980). Changes in predation by the juvenile goby Deltentosteus quadrimaculatus (Teleostei, Gobiidae). Neth. J. Sea Res. 14(3-4): 362-373
In: Netherlands Journal of Sea Research. Netherlands Institute for Sea Research (NIOZ): Groningen; Den Burg. ISSN 0077-7579, more
Juveniles of the goby Deltentosteus quadrimaculatus hunt at sight lying in wait for their prey. They feed mainly on benthic organisms which are swallowed alive. The stomachs were analysed. The preys counted belong to 11 zoological groups of which seven are crustacean orders. The crustaceans comprise on average 92% of the total number of preys or 85% of the weight of preys. The species composition of the food changes during early growth. The postlarvae feed on zooplankton. Once the gobies reach 15mm total length, the contribution of zoobenthos to their diet increases, to become the almost exclusive food source above 20mm length. They then pass through two stages according to the size of their prey, feeding firstly on meiobenthos and passing over progressively on macrobenthos. This development in the choice of food is related to the goby's behaviour. Food composition also appeared to depend on water depth. For youngsters, the frequency of harpacticoid copepods in the stomach contents decreased with depth whereas the occurrence of amphipods increased. The selective character of predation was also evident from the fact that the mean size of preys increased regularly with that of the gobies. This increase, even as that of the total weight of the stomach contents, followed exponential trends.