The Macquarie perch,Macquria australasica (Pisces: Percichthyidae), of Lake Eildon,Victoria

The results of a field study carried out between 1966 and 1969 indicate that the spawning migrations of Macquarie perch, Macquaria australasica, from Lake Eildon, Victoria, into the inflowing Delatite, Howqua, Jamieson, Goulburn and Big Rivers occurred when water temperatures in the rivers reached 16.5°C. Because of different temperature regimes the times of the spawning migration and spawning differed from river to river. Migrating fish were of a uniform size and were in their fifth to tenth years of life. Recaptures of tagged fish suggest that some fish use the same river each year for spawning. Observations on pre-spawning and spawning behaviour and on the characteristics of the spawning site are recorded. Fecundity of fourteen fish in the size range 305–405 mm standard length varied from 50189 to 107 724 eggs per fish. The virtual disappearance of Macquarie pereh from Lake Eildon was probably caused by a combination of several factors, including changed habitat, overfishing of the spawning stock and predation by, and competition for food with, introduced fish.