The color of Australian bass varies from metallic gold in light sandy streams to the more common bronze or bronze-green coloration in streams with darker substrates and/or some tannic coloration in the water. Deep-sea fish (hapuka, cod, perch groper, gemfish+, blue-eyed cod) Dams and spillways that block the migration of Australian perch to estuaries and upper freshwater foothills of coastal rivers are the main cause of the decline.  Most coastal rivers today have dams and spillways. When Australian perch is prevented from migrating through an impassable dam or weir to breed in estuaries, it becomes extinct above that dam or weir. Some dams or spillways exclude the Australian perch from the vast majority of its habitat. For example, it is estimated that the Tallowa Dam on the Shoalhaven River, once an Australian stronghold of bass, currently excludes wild Australian perch from more than 80% of its former habitat (however, a „fish elevator” was installed on the dam in early 2010). Dams and spillways also reduce or eliminate the flooding necessary for the effective reproduction of adult perch and the effective recruitment of juvenile Australian perch. A related problem is the myriad of other structures along coastal rivers, such as poorly designed road crossings that block (often unnecessarily) the migration of the Australian perch. The Australian perch is found at its highest altitude in the freshwater areas of rivers during the months of December, January and February. Research shows that there is gender segregation for resource sharing purposes during this spawning-free season.
 Males inhabit the lower freshwater streams of rivers, while females move far into the middle and even upper freshwater foothills (highlands). The distance travelled by the Australian sea bass upstream seems to be limited only by impassable currents and barriers (historically waterfalls; today often dams). For example, the effective altitude limit for Australian sea bass in some river systems has always been 400 to 600 metres. For example, Australian bass first migrated to the Dalgety area in the Snowy River, well above Oallen Crossing on the Shoalhaven River and far upstream of the Warragamba And Coxs Rivers before these rivers were dammed: another important cause of decline is habitat degradation. Unfortunately, poor land management practices have always been the norm in Australia. The complete clearing of riparian vegetation (river banks), the trampling of banks and the massive siltation caused by these bad practices, as well as bad practices in the watershed, can severely degrade and bewitch coastal rivers until they are uninhabitable for australian perch. The Bega River in southern New South Wales is a particularly salutary example of a coastal river so stripped of riparian vegetation and so silted with coarse granite sand due to poor land management practices that most of it is now completely uninhabitable for Australian perch and other native fish. Australian bass is not found in the Murray-Darling system. Although the system is vast, it ends in a succession of coastal lakes and lagoons and has only a shallow and changing entrance into the Southern Ocean – features that seem incompatible with the breeding habits of australian sea bass and other aspects of its life cycle. However, the Australian perch is a wild predatory fish, and any small creature that swims through a pool of bass, such as mice (introduced) and native lizards or frogs, runs the risk of being attacked by a large Australian sea bass and is regularly taken away. This type of movement leads to some genetic exchange between river systems and is important for maintaining a high level of genetic homogeneity („equality”) in Australian sea bass stocks and for preventing speciation. However, this movement did not prevent different genetic profiles and subtle morphological differences („body shape”) from developing in different flow systems.
   These findings, along with research showing significant differences in the seasonal timing of spawning and migration in populations in the far south, underscore the importance of using appropriate regional stocks of Australian perch for artificial breeding and stocking projects. A rather surprising and unexpected result of this research is that the presumed genus Percalates (i.e. Australian perch and muzzle perch) appears to be genetically closer to the genus Maccullochella (Murray cod and other cod species) than to the residual genus Macquaria (golden bass and Macquarie perch).  In the 1970s, the Australian perch and snout bass were placed in the genus Macquaria – one of the many Australian genera of the Percichthyidae family – along with two species of perch native to the Murray Darling Basin, the golden perch (Macquaria ambigua) and the Macquarie perch (Macquaria australasica).  Before that, Australian bass and muzzle bass belonged to a separate genre, Percalates. (The genus name Percalates is a combination of the genus names Perca and Lates and comes from an early erroneous taxonomic belief that the Australian sea bass was an ancient world perch related to Barramundi (late limestone). Artificial rearing of Australian bass is maintained at much higher salt levels than natural levels. Australian perch fishing is a summer pastime practiced during the warmer months in the freshwater areas of the rivers they inhabit. The Australian perch is eagerly caught as it is an excellent sport fish, exceptionally fast and powerful for its size.
Their exceptional speed and power are probably due to their large and arduous annual hikes to spawn and a generally migratory way of life. The Australian perch in their natural river habitats should not be underestimated; They head straight to the next hooks (sunken wood) when hooked, and light but powerful tackles with rigid drag settings are required to stop them.   For fishermen, it should be remembered that wild Australian perch is still highly migratory in freshwater areas of rivers and can also be an extremely cautious fish in these habitats, much more so than exotic trout species. Australian sea bass adults and larvae can also enter the sea during winter spawning during periods of high tide (the latter may be unintentionally). It has been reported: Lake Bulls Merri: a total of 5 for one or more species of Australian perch, mouth perch and hybrid species. A general description of the typical migration pattern of adult Australian perch in the central (NSW) part of their range would be as follows: As a slow-growing fish, australian perch is prone to overfishing, and overfishing has been a factor in the decline of Australian perch stocks in recent decades. However, the situation has improved considerably as the majority of fishermen practice catching and releasing Australian sea bass. Australian wild perch stocks have declined sharply since European colonization.
Steindachner does not explicitly state the reasons for the surprisingly ambiguous specific name novemaculeata, which he created for australian bass. There are several possibilities. It may be a Latin interpretation of „new” (novem) and „spotted” (maculeata) and refer to the pronounced black spots with which young bass are temporarily marked when they are very small (i.e. <6–7 cm). It could be a Latin rendering of "in an unusual way" (nove) and "spotted" (maculeata) and refer to the fact that the specimens he studied were "spotted": the Australian perch is found in coastal rivers and streams from Wilson`s promontory in Victoria to the east and north along the east coast to the rivers and streams of the Bundaberg region of central Queensland. All other Victorian waters: a total of 5 fish (no more than 2 of which may be Australian perch) Australian perch farming and stocking is used to create fisheries over dams and spillways, but these raise concerns about genetic diversity issues, the use of perch squid from different genetic strains, and the introduction/relocation of undesirable harmful fish species. in the shallows. Stocking can also mask attention and divert attention from severe habitat degradation and declining game populations in watersheds.
Some of Australia`s best perch fisheries are coastal rivers and tributaries where access is difficult. Fishing in these more remote locations can be extremely rewarding for fishing and the landscape. Fishing in the more distant bass water is therefore usually the domain of the hardened backpacker or the dedicated kayak fisherman who is willing to pull his kayak on many tree trunks and other obstacles. The Australian perch (Macquaria novemaculeata) is a small to medium-sized species of fish mainly freshwater (but spawning estuary) found in coastal rivers and streams along the east coast of Australia. A member of the genus Macquaria (although some researchers place it more in the genus Percalates) of the family Percichthyidae (temperate perch), the Australian bass is an important member of the native fish collections found in the river systems of the East Coast. It is a native predatory fish and a species of wild fish extremely popular among fishermen.   The species was simply called perch in most coastal rivers, where it was caught until the 1960s, when the name Australian Bass gained popularity.  Australian bars are powerful swimmers of all sizes and can easily cross rapids and fast-flowing water. However, they usually avoid sitting directly in the currents to save energy. Responsible fishermen now avoid fishing for wild Australian perch in estuaries in winter so that this increasingly pressured native fish can spawn at rest.