Based on encouraging results from the fingerling tank trials (see results section), it was decided to proceed with field trails where trained hatchery-reared fish were stocked into the wild and their survival could be compared with untrained control fish. It was also decided to test the effectiveness of predator free enclosures (soft releases) to enhance post-stocking survival.
Selection of stocking sites
Three stocking sites were selected in the Condamine catchment. Cotswold Dam (a 250 ha dam on a tributary 800 m above its junction with the Condamine River), Reilly’s Weir (on the Condamine River) and Caliguel Lagoon (a large permanent waterhole on an anabranch of the Condamine River). A fourth site was added to the study in the upper Dumaresq catchment at Storm King Dam near Stanthorpe. This site was added because several flood events caused sampling difficulties at Reilly’s Weir. Predatory fish were known to be present at all sites, and other predators including piscivorous birds and turtles were also present. The location of all sites is shown in Figure 7. Figure 8 shows the habitat characteristics of each site.
Figure 7: Map showing location of study sites (red dots).
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