They have been known to grow to lengths of two metres or more. Potato cod can grow to weights of 100 kilos! They are very slow growing and to reach such a large size would take a very long time. The average adult is 1.5 metres long, weighing about 90 kilos.

Potato cod like to ambush their prey by hiding behind lumps of coral until their food swims past. They then lunge quickly and grab their meal. Large potato cod have such big mouths that they can often eat their prey in one gulp. Potato cod eat rays, crabs, squid, octopus, fish and western rock lobsters.

Potato cod are very inquisitive and like to check out human visitors, if the divers are careful they can get very close to them. As potato cod live in the same area throughout their life, fishers can locate these large fish easily. This means they are easy targets for spear fishers. This is one reason why potato cod are protected in WA.

Large potato cod like to live by themselves most of the time. They do get together in large groups when they are ready to spawn. Each fish might swim several kilometres to get to the spawning site. This is a long distance for potato cod as they don’t usually swim too far from their home.

Potato cod are ‘protogynous hermaphrodites’ which means they start their life as a female and as they get older become male. Not too much is known about this and it is possible that not all females become males and not all males start as females.

Scientific and other names
Potato cod ( Epinephelus tukula) are part of the groper family. Groper are commonly called cod in Australia. The second part of the potato cods name tukula is from a Malagash word which means ‘man-eater’. Potato cod are also known as potato grouper or potato bass in other ares of the Indo-Pacific region.

What they look like
The adult potato cod is pale bluish-grey in colour and covered with large dark brown or black blotches. There are dark spots and streaks on their head. Very large adults are reported to be almost entirely black. Juveniles have the same colour pattern and colourations as adults.

Where they live
Potato cod like to live among coral reefs from Ningaloo reef and north to the Northern Territory boarder, sometimes they can be seen further south. They move around the bottom of the reefs looking for food. Juveniles will be found in the shallow water of reef tidepools. The majority of large potato cod live by themselves in the same reef area, often for years.