Introduced to the Murray-Darling basin, in the State of New South Wales (NSW) and released in the freshwaters of highland areas. Also introduced to Tasmania with a reproducing population in Clarence Lagoon, Tasmania (Ref. 7300). Also known from streams and lakes of the Tyndall Ranges, Tasmania, and from the one stream near Armidale, NSW (Ref. 44894). The species has established self-sustaining populations in at least five streams and several lakes in New South Wales. It has been stocked, and is now also established by natural reproduction in the Thredbo River (including its tributary Little Thredbo River, and Lake Crackenback), Lake Jindabyne (near Jindabyne), Three Mile Dam (near Kiandra), Dry Dam (near Cabramurra), Rainbow Lake (near Perishers Creek), the upper Tooma River (near Khancoban), Ogilvies Creek (a tributary of the Tooma River), Pinch River and Jacobs River (near Ingebyra). In Tasmania, the species' distribution has been expanded considerably in recent times. While the Clarence Lagoon and Clarence River population continues to flourish, there are also self-sustaining populations in the Anthony/Henty river systems on the West Coast of Tasmania. The large hydro-generating Lake Plimsoll (near Tullah) and the nearby natural waters Lake Rolleston and Lake Selina (and their tributaries) all contain self-reproducing populations of brook trout. In addition to these established populations, hatchery reared brook trout (1+ aged fish) now also comprise a significant share of the liberations of trout made for ‘put-and-take’ angling purposes within Tasmania’s Central Plateau and lower elevation hydroelectricity reservoirs such as Dee Lagoon, Bronte Lagoon (near Bronte Village), Brady’s Lake, Lake Binney (near Tarraleah), Lake Leake (near Campbell Town) Lake Meadowbank (near Maydena), Brushy Lagoon (near Westbury) and Craigbourne Dam (near Colebrook) (Glen Power, pers. Comm., 2007).

The species has self-sustaining populations in at least five rivers and one lake in New South Wales. They are the Thredbo River and its smaller tributaries and Lake Jindabyne (Snowy Mountains), Ogilvies Creek (a tributary of the Tooma River, NSW, where the species was stocked in the 1980s and 90s), the Pinch and Jacobs Rivers (tributaries of the Snowy River) and one stream in the New England Tablelands District of New South Wales. In Tasmania, the species' distribution has been expanded considerably in recent times. While the Clarence Lagoon and Clarence River population continues to flourish, there are also self-sustaining populations in the Anthony/Henty river systems on the West Coast of Tasmania. The large hydroelectric lake and the nearby natural lakes Rolleston and Selina (and their tributaries) all contain brook trout (Glen Power, pers. comm., 2001).