Marine and Freshwater Research Marine and Freshwater Research Society
Advances in the aquatic sciences

Effects of freshwater flow on the year-class strength of a non-diadromous estuarine finfish, king threadfin (Polydactylus macrochir), in a dry-tropical estuary

Ian A. Halliday A C , Julie B. Robins A , David G. Mayer B , Jonathan Staunton-Smith A and Michelle J. Sellin A
+ Author Affiliations
- Author Affiliations

A Department of Primary Industries and Fisheries, Southern Fisheries Centre, Deception Bay, Qld 4508, Australia.

B Department of Primary Industries and Fisheries, Animal Research Institute, Locked Mail Bag 4, Moorooka, Qld 4105, Australia.

C Corresponding author. Email:

Marine and Freshwater Research 59(2) 157-164
Submitted: 13 April 2007  Accepted: 11 January 2008   Published: 27 February 2008


The year-class strength of the commercial catch of king threadfin (Polydactylus macrochir (Gunther, 1876)) was correlated with freshwater flows into a dry-tropical estuary over five consecutive years. The year-class strength of king threadfin, a non-diadromous estuarine species, fluctuated and correlated significantly with freshwater flow and coastal rainfall in spring and summer; a result similar to that found for the catadromous barramundi (Lates calcarifer) within the same estuarine system. All sub-sets general linear models were used to screen relationships between year-class strength and freshwater variables. King threadfin spawn from spring to summer in north-eastern Australia, when hydrological conditions adjacent to estuaries have high salinities and are optimal for egg and post-larval survival. Young-of-the-year enter estuaries during the wet season, enabling them to take advantage of salinity gradients and the seasonal blooms in prey species such as Acetes spp. and juvenile penaeids that are accentuated in wet years. Freshwater flows in spring and summer are important drivers of the year-class strength of estuarine finfish, and reduction in these flows, through the development of water infrastructure and abstraction or long-term climate change, will potentially reduce the size of the population of estuarine fish available for human harvest.

Extra keywords: environmental flows, fish recruitment, otoliths, year-class strength (YCS).


The present study was funded by the Cooperative Research Centre for Coastal Zone Estuary and Waterway Management and the Fisheries Research and Development Corporation. We thank the seafood processors and commercial fishers of the Fitzroy River region for their cooperation and allowing access to the commercial catch of king threadfin. Technical support was provided by Richard Marsh, Nicola Barnard, Marie Younger and Denise White. We also thank Infofish Services for providing access to the ANSA tag–recapture data and Gary Hargraves, Hans Mulder, Mike Keane (Department of Natural Resources, Mines and Water, Queensland) and Quentin Rider (Fitzroy River Water) for providing freshwater flow data.


Aleem, A. A. (1972). Effect of river outflow management on marine life. Marine Biology 15, 200–208.
CrossRef |

Bonvechio, T. F. , and Allen, M. S. (2005). Relations between hydrological variables and year-class strength of sportfish in eight Florida waterbodies. Hydrobiologia 532, 193–207.
CrossRef |

Brewer, D. T. , Blaber, S. J. M. , Salini, J. P. , and Farmer, M. J. (1995). Feeding ecology of predatory fishes from Groote Eylandt in the Gulf of Carpentaria, Australia, with special reference to predation on penaeid prawns. Estuarine, Coastal and Shelf Science 40, 577–600.
CrossRef |

Cardona, L. (2000). Effects of salinity on the habitat selection and growth performance of Mediterranean flathead grey mullet Mugil cephalus (Osteichthyes, Mugililidae). Estuarine, Coastal and Shelf Science 50, 727–737.
CrossRef |

Clewett J. F., Clarkson N. M., George D. A., Ooi S. H., Owens D. T., Partridge I. J., and Simpson G. B. (2003). Rainman StreamFlow version 4.3: a comprehensive climate and streamflow analysis package on CD to assess seasonal forecasts and manage climate risk. Queensland Department of Primary Industries, Information Series QI03040, Brisbane.

Copeland, B. J. (1966). Effects of decreased river flow on estuarine ecology. Journal of Water Pollution and Control Federation 38, 1831–1839.

Drinkwater K. F. (1986). On the role of freshwater outflow on coastal marine ecosystems: a workshop summary. In ‘Proceedings of the NATO Advanced Research Workshop on the Role of Freshwater Outflow in Coastal Marine Ecosystems’. (Ed. S. Skreslet.) pp. 429–438. (Springer-Verlag: Germany.)

Drinkwater, K. F. , and Frank, K. T. (1994). Effects of river regulation and diversion on marine fish and invertebrates. Aquatic Conservation: Freshwater and Marine Ecosystems 4, 135–151.
CrossRef |

FishBase (2006).FishBase. ICLARM: Panang. Available at Accessed April 2007.

Garrett R. N. (1997). Biology and harvest of tropical fishes in the Queensland Gulf of Carpentaria gill net fishery. Queensland Department of Primary Industries, Queensland Fisheries Information Series QI98018, Brisbane.

GenStat (2006). ‘GenStat for Windows, Release 8.1.’ 8th edn. (VSN International Ltd: Oxford.)

Gillanders, B. M. , and Kingsford, M. J. (2002). Impact of changes in flow of freshwater on estuarine and open coastal habitats and the associated organisms. Oceanography and Marine Biology: An Annual Review 40, 233–309.

Halliday I. A., and Robins J. B. (2007). Environmental flows for sub-tropical estuaries: understanding the freshwater needs of estuaries for sustainable fisheries production and assessing the impacts of water regulation. Final Report to the Fisheries Research and Development Corporation. Project No 2001/022, Canberra.

Hecht, T. , and van der Lingen, C. D. (1992). Turbidity-induced changes in feeding strategies of fish in estuaries. South African Journal of Zoology 27, 95–107.

Hilborn R., and Walters C. J. (1992). ‘Quantitative Fisheries Stock Assessment: Choice, Dynamics and Uncertainty.’ (Chapman and Hall: New York.)

Hughes, L. (2003). Climate change and Australia: Trends, projections and impacts. Austral Ecology 28, 423–443.
CrossRef |

Kailola P. J., Williams M. J., Stewart P. C., Reichelt R. E., McNee A., and Grieve C. (1993). Australian Fisheries Resources. Bureau of Resource Sciences, Canberra.

Livingston, R. J. , Lewis, F. G. , Woodsum, G. C. , Niu, X.-F. , Galperin, B. , Huang, W. , Christense, J. D. , Monaco, M. E. , Battista, T. A. , Klein, C. J. , Howell IV, R. L. , and Ray, G. L. (2000). Modelling oyster population response to variation in freshwater input. Estuarine, Coastal and Shelf Science 50, 655–672.
CrossRef |

Loneragan, N. R. , and Bunn, S. E. (1999). River flows and estuarine ecosystems: implications for coastal fisheries from a review and a case study of the Logan River, southeast Queensland. Australian Journal of Ecology 24, 431–440.
CrossRef |

Long P. E., and McKinnon S. G. (2002). Habitats and fisheries resources of the Fitzroy River estuary (Central Queensland). Queensland Department of Primary Industries, Information series QI02104, Brisbane, Australia.

Maceina, M. J. (1997). Simple application of using residual from catch-curve regressions to assess year-class strength in fish. Fisheries Research 32, 115–121.
CrossRef |

Motomura, H. , Iwatsuki, Y. , Kimura, S. , and Yoshino, T. (2000). Redescription of Polydactylus macrochir (Günther, 1867), a senior synonym of P. sheridani (Macleay, 1884) (Perciformes: Polynemidae). Ichthyological Research 47(3–4), 327–333.
CrossRef |

Peters, J. C. (1982). Effects of river and streamflow alteration on fishery resources. Fisheries 7, 20–22.
CrossRef |

Robins, J. B. , Halliday, I. A. , Staunton-Smith, J. , Mayer, D. G. , and Sellin, M. J. (2005). Freshwater-flow requirements of estuarine fisheries in tropical Australia: a review of the state of knowledge and application of a suggested approach. Marine and Freshwater Research 56, 343–360.
CrossRef |

Robins, J. , Mayer, D. , Staunton-Smith, J. , Halliday, I. , Sawynok, B. , and Sellin, M. (2006). Variable growth rates of the tropical estuarine fish barramundi Lates calcarifer (Bloch) under different freshwater flow conditions. Journal of Fish Biology 69, 379–391.
CrossRef |

Russell D. J. (1988). An assessment of the east Queensland inshore gill net fishery. Queensland Department of Primary Industries, Information Series QI88024, Brisbane.

Russell, D. J. , and Garrett, R. N. (1983). Use by juvenile barramundi, Lates calcarifer (Bloch), and other fishes of temporary supralittoral habitats in a tropical estuary in northern Australia. Australian Journal of Marine and Freshwater Research 34, 805–811.
CrossRef |

Salini, J. P. , Blaber, S. J. M. , and Brewer, D. T. (1990). Diets of piscivorous fishes in a tropical Australian estuary, with special references to predation on penaeid prawns. Marine Biology 105, 363–374.
CrossRef |

Shepherd, J. G. , Pope, J. G. , and Cousens, R. D. (1984). Variations in fish stocks and hypotheses concerning their links with climate. Rapports et Procès-Verbaux des Réunions du Conseil International pour l’Exploration de la Mer 185, 255–267.

Sobrino, I. , Silva, L. , Bellido, J. M. , and Ramos, F. (2002). Rainfall, river discharges and sea temperature as factors affecting abundance of two coastal benthic cephalopod species in the Gulf of Cadiz (SW Spain). Bulletin of Marine Science 71, 851–865.

Staunton-Smith, J. , Robins, J. B. , Mayer, D. G. , Sellin, M. J. , and Halliday, I. A. (2004). Does the quantity and timing of freshwater flowing into a dry tropical estuary affect year-class strength of barramundi (Lates calcarifer)? Marine and Freshwater Research 55, 787–797.
CrossRef |

Stuart, I. G. , and McKillup, S. C. (2002). The use of sectioned otoliths to age barramundi, Lates calcarifer (Bloch, 1790) [Centropomidae]. Hydrobiologia 479, 231–236.
CrossRef |

Whitfield, A. K. (2005). Fishes and freshwater in southern African estuaries: A review. Aquatic Living Resources 18, 275–289.
CrossRef |

Williams L. (2002). Queensland’s fisheries resources. Current condition and recent trends 1988–2000. Queensland Department of Primary Industries, Queensland Fisheries Information Series QI02012, Brisbane.

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