The eastern gobbleguts (Vincentia novaehollandiae) is a species of cardinalfish endemic to Australia’s southern coast. Like other cardinalfish, it is the male’s responsibility to care for the eggs, which he stores in his mouth until they are ready to hatch. What makes this otherwise drab-coloured fish stand out is the vivid colour of its egg clutch—bright orange when the eggs have just been transferred.

Southern summer is their mating season, and the best time to spot these usually discreet fish. At night, they venture out from the shelter of kelp and rock ledges to find a mate, with a chance to see a male carrying its brood, if you go slow and spend time looking.

This is one of my favourite subjects to photograph during night dives in Sydney Harbour. I used a single, directional strobe to help the subject pop against the murky background.