Lake Eyre Basin Rivers 38 native Australian fish species. Since 2009, intensive management has focused on recovery of red-finned blue-eye using three control techniques: use of the piscicide rotenone to remove gambusia, relocation of red-finned blue-eye (using a founder populations of 20 individuals) to safe habitats where gambusia have been removed or do not occur, and the installation of barriers around some springs to prevent gambusia colonisation (Kerezsy and Fensham 2013 Kerezsy 2015). Alien invasions Unlike the neighbouring and similarly sized Murray–Darling Basin, the Lake Eyre Basin and its rivers remain unregulated, with relatively few alien aquatic species in relatively low numbers (see Chapter 4). Carp (Cyprinus carpio), redfin (Perca fluviatilis) and various salmonids (trouts and salmon) are absent from the Bulloo, Cooper, Diamantina and Georgina Rivers. Small populations of gambusia and goldfish live throughout Cooper Creek (Table 3.1), although their impacts are largely unknown (with the exception of impacts on the spring species mentioned above). However, several translocated native fish species have established in the Lake Eyre Basin rivers, and they were probably first introduced by government agencies and/or local fishing clubs for recreational fishers or aquaculture. The largest and most iconic Murray–Darling Basin fish, Murray cod (Maccullochella peelii) was introduced into the Thomson River at Longreach in the Cooper Creek catchment in the late 1980s and early 1990s individuals still show up occasionally (A. Emmott, pers. comm.). This fish is a top order predator in rivers where it naturally occurs, and therefore has the potential to negatively impact populations of naïve prey species in rivers where it is translocated. From the 1980s to the early 2000s, far larger numbers of yellowbelly (Macquaria Fig. 3.4. The endemic and endangered Edgbaston goby, with a global population existing in only nine springs at Edgbaston and at two locations on adjacent properties in the Aramac district in central western Queensland (photo, A. Kerezsy).