Yellowfin Bream Research Articles

An assessment of the angling fishery for yellowfin bream, Acanthopagrus australis (Günther), in Moreton Bay, Australia

Yellowfin bream, Acanthopagrus australis, support an important angling fishery in Moreton Bay, a large estuarine system on the east coast of Australia. An analysis of the records of catches by anglers indicates that abundance and mean size of yellowfin bream have changed little in Moreton Bay during the period 1945 to 1980. Over the past 5 years substantial increases have occurred in the total angling effort for yellowfin bream at surf bar spawning areas in Moreton Bay. This has resulted in a decrease in mean catch per unit effort but no apparent decrease in total yield. Reclamation and development projects which cause degradation of the surf bar spawning areas have the greatest potential to cause reduction in abundance of yellowfin bream in Moreton Bay.

Spawning period and growth of yellowfin bream, Acanthopagrus australis (Günther), in Moreton Bay, Australia

Monthly changes in the gonosomatic index indicate that yellowfin bream, Acanthopagrus australis, in Moreton Bay have a short spawning season with a peak during the period July to August each year. The growth rate of A. australis was estimated from tag‐recapture data and by length‐frequency analysis. Modes representing age classes 0, I and II often appeared in length‐frequency distributions, however modes for older age classes were difficult to identify. The von Bertalanffy growth curve parameters calculated from release–recapture data are: L∞= 29.5 cm; K= 0.51; t0=– 0.32 years.

Movements and migrations of yellowfin bream, Acanthopagrus australis (Günther), in Moreton Bay, Queensland as determined by tag recoveries

Yellowfin bream were tagged and released in three non‐spawning areas and two spawning areas in Moreton Bay, a large estuarine system on the east coast of Australia. A total of 194 fish were recaptured. Juvenile fish made only small‐scale movements (less than 6 km) from the release site. Small‐scale movements were also recorded for adult fish, although large‐scale movements from 10 to 90 km were also recorded. The large‐scale movements appear to be associated with the migration of adult fish to or from surf bar spawning areas. Some adult fish remained in feeding areas during the spawning season (May‐August). There was no indication from tag recoveries of any movements of yellowfin bream outside Moreton Bay and the results indicate that adult yellowfin bream in Moreton Bay may be regarded as a unit stock for the purpose of fisheries management.

The effects of fish on growth and survival of school prawns Metapenaeus macleayi (Haswell) in some Australian brackish water farming ponds

Juvenile tarwhine ( Rhabdosargus sarba) and yellowfin bream ( Acanthopagrus australis) were shown to be competitors with school prawns in farming ponds. Relatively small yellowfin bream also appeared to be predators of these prawns. In contrast, sea mullet ( Mugil cephalus), tiger mullet ( Liza argentea), silver-biddies ( Gerres ovatus), transparent gobies ( Gobiopterus semivestita) and estuarine shore crabs ( Paragrapsus laevis) apparently had little effect on school prawns. The above relationships are discussed in terms of dietary overlap and a detailed description of the stomach contents of school prawns from a farming pond is given. The effect of sea mullet stocking density on the growth of this species of fish is briefly discussed.