Thanks Marks. I've been meaning to write a scientific paper about this issue for years (Murray cod reproduction in impoundments). I must get on with it!
- Unfortuantely most the eggs in this particular shot appear to be dead (white, opaque insteady of yellowish, translucent). More concerningly, there seems to be a fair bit of Saprolegnia parasitica infection of the eggs (the greyish hazy stuff). Perhaps in the absence of river currents Murray cod struggle to keep Saprolegnia infection of their eggs matts at bay. (Saprolegnia is a notorious and intractable infector of Murray cod eggs in hatcheries.)
- Beautiful, beautiful fish. Love the patterning on the forehead and the pectoral fins.
- This is amazing footage, and it offers insights into Murray cod reproductive behaviour. However, I would urge a bit of caution in obtaining such footage, in regards to getting too close and scaring off the male fish guarding the eggs. It has been the experience of other researchers investigating the closely related eastern freshwater cod (M. ikei) that 'spooked' male fish do not necessarily return to the nest to pick up their nest guarding behaviour again, and in that case, the nest is rapidly destroyed by various predators including turtles and Macrobrachium shrimp (refer to papers by Rowland and Butler).