Distributed throughout the Murray-Darling river system, except for those streams at altitudes higher than about 600 m. The northern limit of the species' natural distribution is the headwaters of the Georgina River (Ref. 2906). Golden perch also inhabit rivers in the eastern Lake Eyre and Bulloo drainages, the Dawson-Fitzroy river system in south-eastern Queensland and in many of the floodplain lakes of western Victoria and New South Wales. They have been stocked in farm dams and reservoirs outside of their natural range (Ref. 27439).

Stock structure: Genetic data from a study (Ref. 27444) indicate that Macquaria ambigua is most probably composed of two different species, with each species comprising two distinct subspecies. Because the type material for M. ambigua is recorded only from localities within the Murray-Darling basin (Ref. 7300), golden perch from central Australia must be regarded as a new species. Until this new species is described formally, it will be referred to as the 'central Australian form of M. ambigua (Ref. 27444). Furthermore, this 'central Australian form' of M. ambigua comprises two subspecies - each from Lake Eyre drainage and Bulloo River. M. ambigua oriens is a subspecies of M. ambigua, from the Fitzroy River (Ref. 27444).

Commercial fishery: Golden perch have been part of the catch from the inland fishery since its inception in the mid to late 1800s (Ref. 27446). In the early 1900s they constituted about 25% of the catch, of which the rest was Murray cod, Maccullochella peeli peeli (Ref. 27446). With the decline in Murray cod numbers, golden perch has become the dominant native species in inland catches.

The inland fishery is centred on the lower reaches of the Murrumbidgee, Lachlan and Murray rivers and associated floodplain lakes in New South Wales and South Australia. Fishers also work in Lake Albert and Lake Alexandrina in South Australia and lakes and backwaters associated with the Darling River in New South Wales (Ref. 27447, 26403). The fishery is opportunistic, i.e. it operates in response to seasonal flooding.

Drum nets and gillnets are used to catch golden perch. Drum nets are the favoured method in rivers. They are checked twice daily when fish are running, less frequently at other times (Ref. 27448). Gillnets are used in the lake fishery and in slow flowing backwaters.

The fishery targets adult fish. The catch is strictly for domestic markets and is sold locally (Ref. 27447), or as wet, gutted fish through the Sydney, Melbourne and Adelaide fish markets.

Recreational fishery: Golden perch are taken by anglers throughout their natural range. Most effort centres on impoundments throughout southeastern Australia that have been artificially stocked. Fishing effort is heaviest in the spring and summer months. In rivers, effort increases during flooding when fish begin to migrate. Large numbers of fish may accumulate below weirs and barriers when migrating and so become easy targets for anglers.

Golden perch are caught using handlines, rod-and-line or set lines. Artificial lures have been used but live baits such as worms, yabbies (Cherax species), 'bardi grubs' (burrowing moth and beetle larvae - Lepidoptera) and small fish are more successful. A creel survey of catch in a New South Wales reservoir in 1981-82 estimated a recreational catch of 50 t, equal to 13% of the commercial catch for that year (Ref. 27439). This suggests that the recreational catch is significant. The largest golden perch in the records of the Australian Anglers Association is a 7000 g fish taken in New South Wales in 1975.

Resource status: Catches of golden perch fluctuate widely, and abundance is thought to be related to flooding (Ref. 26403). Construction of dams and weirs throughout the Murray-Darling river system has altered both flow and thermal regimes. Changes induced by such barriers in the Murray River flooding regime may also affect catch sizes. Furthermore, because golden perch move extensively, high barriers without facilities for fish passage limit the amount of river available to them.

While catches remain good, the range and abundance of golden perch has declined since European settlement (Ref. 27450). Illegal use of drum nets and gillnets in remote western rivers is a major management problem. Also Ref. 2156, 44894.