Spatial, temporal and size-class variation in the diet of estuary perch (Macquaria colonorum) in the Hopkins River, Victoria, Australia

• Published in: Hydrobiologia Vol. 515; no. 1-3; pp. 29 - 37
• Main Authors: HOWELL, Timothy, LAURENSON, Laurie Jon, MYERS, Jackie H, JONES, Paul L
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer 01.03.2004; Springer Nature B.V
• Subjects: Agnatha. Pisces; Animal and plant ecology; Animal, plant and microbial ecology; Animals; Aquatic ecosystems; Autoecology; Biological and medical sciences; Brackish; Diet; Estuaries; Fish; Fundamental and applied biological sciences. Psychology; Macquaria colonorum; Paratya australiensis; Predation; Vertebrata; Australia; Victoria; Oceania; Australia, Victoria; ISW, Australia, Victoria, Hopkins Estuary; Brackish water environment; Estuaries; Rivers; Macquaria colonorum; Feeding; Freshwater environment; estuary perch; Aquatic environment; Vertebrata; Hydrobiology; Diet; Pisces; Victoria estuary freshwater; Teleostei; Osteichthyes
• ISSN: 0018-8158; 1573-5117
• DOI: 10.1023/b:hydr.0000027315.51291.fd

The dietary importance of prey of estuary perch (Macquaria colonorum; Percicthyidae: Günther) was examined spatially, temporally and among size classes. Fish were collected from the Hopkins River, south-western Victoria, from September 1998 to February 1999. The species is a euryhaline, euryphagic carnivore with spatial, temporal and size class variations in diets. Fish caught from estuarine locations consumed primarily Paratya australiensis (40% IRI) while freshwater fish consumed mostly Tricopteran larvae (63.5% IRI). In both freshwater and estuarine locations, the relative importance of P. australiensis decreased with increasing length of fish. Diet changed seasonally, indicating opportunistic changes in prey. The species selected particular prey items relative to environmental availability (P. australiensis, Amarinus lacustrine).[PUBLICATION ABSTRACT]