Project number: 1995-025
Budget expenditure: $28,550.00
Principal Investigator: Bob Black
Organisation: University of Western Australia (UWA)
Project start/end date: 26 Jun 1995 - 25 May 2000
1. The aim of this research programme is to provide data needed for the effective management of serranids, including: Ecological and biological data on the chinaman cod within the Ningaloo recreational fishery.
2. Experimental simulation of line fishing on chinaman cod populations to determine how the social system of this fish is affected by fishing, and its ability to withstand such pressure.
3. Experimental manipulation of chinaman cod social units to determine the mechanisms controlling sex change and the effects of sustained fishing pressure on these mechanisms.
4. Biological and catch data on the bar-cheeked coral trout caught in the Pilbara trawl fishery. A solution to the present wastage of undersized trout caught in this fishery will also be sought.
Author: Robert Black
Final Report • 2000-01-10 • 2.84 MB
This study provides detailed biological and ecological information on the chinaman cod, Epinephelus rivulatus, and biological information on the bar-cheeked coral trout, Plectropomus maculatus, in West Australian waters. Both of these species are members of a large group of predatory fish known as the epinepheline serranids. Serranids are found throughout the tropical and subtropical marine waters of the world, and are valued catches within numerous fisheries. Although some species in the Caribbean have been well studied, there is generally a lack of detailed biological and ecological data on the serranids. In particular, there is little information on the processes controlling sex change in serranid species. This life history pattern, along with the fact that many are long lived and slow growing, may leave serranids particularly vulnerable to fishing pressure. However, without information on the mechanisms controlling sex-change, specific management options for serranid species remains somewhat speculative.
Various serranid species are targeted or caught as by-catch in Australian tropical waters. Nevertheless, apart from coral trout inhabiting the Great Barrier Reef, the biology and ecology of Australian serranids is poorly understood. The present study focussed on the chinaman cod since it is an important species within the Ningaloo Reef recreational fishery. Because it is abundant and accessible, the chinaman cod was also amenable to the logistically difficult task of determining the mechanisms of sex-change in this species. The study of coral trout biology was commenced in response to the capture of undersized fish within the Pilbara trawl fishery. As the current size limit may not be biologically appropriate, samples obtained from the trawl fishery were used to learn more about the biology of this species.