Ask Dr Dazza | Queensland Groper

THERE has been much excitement in local recreational fishing circles this week by the capture (and safe release) of a Queensland groper in the Pine River.

It is certainly a very rare, but not unknown catch in the local waters. A 500lb specimen was captured in the 1970s by an angler in the Caboolture River.

Queensland groper is one of the largest bony fish, reaching a maximum length of three metres and weight of more than 600kg. That’s a lot of fish. Queensland groper have been totally protected in Queensland for a long period of time.

The Queensland groper belongs to the Family Serranidae which also includes common angling species such as coral trout and estuary cod. Like many members of the family, they are hermaphrodites - the young are predominantly female but turn into males as they develop. The species aggregates for spawning but may not spawn every year.

Both adults and juveniles can be found on a variety of habitats like estuaries such as the Pine River right out to offshore reefs. Many lagoons in the Swains Reef have resident populations of Queensland groper. Although the adults are a drab brown, small juveniles have striking yellow markings.

They are a widely distributed fish, being found in Australia from south of Sydney northwards and all around northern Australia and then down as far as Shark Bay. Elsewhere in the world, they are found in the waters of India, Japan, Fiji, Hawaii, Philippines, Kenya and Tanzania to name a few.

While their diet is very broad, adult Queensland groper on coral reefs have expensive tastes – they prefer eating crayfish. Overall, they also eat other large fish, sharks, mud crabs and marine turtles.

Due to their fast growth rate and market demand for the small colourful juveniles, they are farmed in many countries, although most of the farmed fish tend to be hybrids with the flowery cod. They can be farmed in large indoor tanks or ponds.

A specimen washed up in northern NSW of 2.2m was aged at 37 years.