ASFB Home > 2003 > Biological Invasions: Consequences for Parasites, Pathogens, Emerging Diseases, and Fisheries in the Marine Environment.

The influence of climate on the catch of King George whiting in Victorian bays and inlets

Greg Jenkins

Marine and Freshwater Resources Institute and Department of Zoology, University of Melbourne, P.O. Box 114, Queenscliff Vic 3225 Australia.
Email: greg.jenkins@nre.vic.gov.au

The King George whiting fishery in Victoria, Australia is based on sub-adult fish of 3 – 5 years age in bays and inlets. Previously, zonal westerly winds and the El Niño southern oscillation index (ENSO) cycle had been found to influence the larval stages and subsequent catches of some fishery species in south-eastern Australia. Offshore spawning and long larval life, together with a fishery based on a few year classes of juvenile fish, led to the hypothesis that the fishery would be strongly influenced by climatic conditions in the larval stage. A positive significant correlation was found when catch lagged the strength of westerly winds in the region by 5 years. These conditions may have influenced larval transport rates, or alternatively may have led to increased plankton productivity and therefore larval food supply. The ENSO cycle, however, was found to have an influence on catch at shorter lags, indicating an affect on the juvenile stages. This positive correlation suggested that La Niña, with low barometric pressure and associated conditions, such as increased rainfall, has a positive affect on growth and/or survival of juveniles. Finally, strong westerly winds have a direct negative affect on catches in the corresponding year. Overall, results suggest that climatic conditions exert a strong influence on this fishery, both in the larval stage occurring offshore, and the juvenile stage in bays and inlets. The results have implications both for forward prediction of catches and also the possible long-term effects on the fishery of climate change.

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