Otherwise known as the freshwater or eel tailed catfish, it builds a nest of pebbles and gravel with coarser material in the centre. The eggs are laid in the nest and take around 7 days to hatch. The male fish patrols the nest diligently during this time to clean or aerate the nest and guard the eggs from predators.
The one below spends all day chasing off nearby fish. You can make out the nest in the photo. It's roughly circular (taking up most of the photo) and consists of larger pebbles in the middle moving to smaller pebbles and gravel towards the outside.
Numerous threats have contributed to the catfish's decline in many Australian river systems. Concern has been expressed about the potential impacts of Carp and Redfin perch, cold-water pollution below dams, barriers to movement, changes to natural flow regimes and elevated salinity levels (juveniles have much lower salinity tolerance than adults) on the catfish population. The lack of formal recognition as a threatened species has hampered conservation efforts. Thankfully none of these potential problems occur in the river where our little neighbour makes his home.