Feeding patterns of Nesogobius sp., Gymnapistes marmoratus, Neoodax balteatus and Acanthaluteres spilomelanurus from a Tasmanian seagrass meadow

Abstract

The diet, feeding chronologies, gastric evacuation rates and daily ration of four species of fish from a seagrass meadow in south-eastern Tasmania were determined by field and laboratory studies. Nesogobius sp. is an active species feeding mainly as intertidal regions are flooded and taking predominantly errant polychaetes and amphipods. G. marmoratus feeds continuously, mainly on malacostracan crustaceans. N.balteatus and A. spilomelanurus both feed only during the daylight hours; the former feeds mainly on slow-moving and benthic animals and some zooplankton whereas plant material and zooplankton are important in the diet of the latter. The gastric evacuation rate and daily lation are lowest in G, marmoratus. N. balteatus and A. spilomelanurus have high evacuation rates and, together with Nesogobius sp., high daily rations. These differences are probably due to the proportion of time spent feeding, the quality of the dietary items, and activity patterns.