In situ feeding rate and diet selectivity in Tasmanian mysid species (Crustacea, Mysidacea)

We determined in situ feeding rates of three co-occurring coastal mysid species using [methyl-³H]-thymidine-labelled algal detritus (Lessonia corrugata), NaH¹⁴CO₃-labelled phytoplankton (Isochrysis galbana) and zooplankton (Artemia sp. nauplii). All three species showed a wide and overlapping range of feeding rates on the three food types, suggesting they were broadly omnivorous. However, selectivity studies often showed a strong preference for animal prey. Although there was an overlap in the types of food the mysids ingested, some degree of feeding niche partitioning was demonstrated. Paramesopodopsis rufa tended to be more carnivorous, Tenagomysis tasmaniae fed least on zooplankton and phytoplankton, and largely on algal detritus, and Anisomysis mixta australis ingested few zooplankters, and moderate amounts of algal detritus and phytoplankton.