Rankin Cod
Offshore / ReefWA-endemic tropical grouper of the Pilbara and Gascoyne, found across rubble bottom and broken reef from around Shark Bay north. Often comes up alongside red emperor on the same demersal rigs and shares the same 40–100m depth range. One of the better-eating grouper species on the WA coast and a regular guest in the mixed northern demersal bag.
Overview
Rankin cod (Epinephelus multinotatus) are a WA-endemic grouper, distributed from roughly Shark Bay north through the Gascoyne and Pilbara into Kimberley waters. They live on rubble, broken reef and coral edges in 30–100m, often holding alongside red emperor, spangled emperor and goldband snapper, and they're a routine catch on the same paternoster rigs that target reds. The Gascoyne and North Coast bioregions hold the bulk of the recreational fishery — charter boats out of Coral Bay, Exmouth, Onslow and Dampier put clients onto rankin most trips. Despite the shared 'cod' label with the unrelated coral trouts (Plectropomus species), rankin cod is a true Epinephelus grouper with a paler, mottled body and a dark tail margin.
Identification
Rankin, Rankin's cod, white-blotched grouper
A solid, big-mouthed grouper with rounded fins, pale grey-brown to olive, covered in irregular white blotches that fade in and out with the fish's mood, plus scattered darker flecks and a dark margin along the tail. The tail edge is the detail worth remembering — it stays put when the blotching does not. Coral trout share the reef but are more streamlined, distinctly blue-spotted and a different colour entirely. Other Epinephelus rockcods coming up on the same rigs are generally more heavily spotted or barred. Breaksea cod are a southern fish and do not overlap with rankin country.
How to Catch
Whole squid, butterflied mullet, slimy mackerel fillet, octopus, large pilchards
Slow-pitch jigs 150–300g, large soft plastics on heavy jigheads, vertical knife jigs
Paternoster rig with two 8/0–10/0 circle hooks on heavy droppers and an 80–100lb mono leader — the same rig you'd run for red emperor. Use 16–32oz of lead to hold bottom in deep water and current. Strong knots and quality terminals are non-negotiable; rankin cod fight hard for the bottom on the strike.
Drift or lightly anchor over rubble and reef edges in 40–100m, working baits hard on the bottom with a couple of cranks up. Rankin hold around the corners and edges of structure rather than the peaks, the same as reds. Slow-pitch jigging produces well when fish are aggressive, with short sharp lifts off the bottom. They strike decisively and try to bury you in the reef — lock up immediately and lift them clear before they get their head down. Carry a release weight; barotrauma is real at depth and undersized or surplus fish need to go back properly.
Year-round in northern WA, with the cooler April–October window offering the best weather for the Gascoyne and Pilbara grounds. Tide changes trigger the bite; neaps make bottom-fishing easier than springs. Dawn and dusk are most productive, but rankin will feed through the middle of the day on the right tide.
Up to 15kg, commonly 3–8kg
Year-round (Gascoyne, Pilbara)
Size & Growth
Commonly 3–8kg on the Gascoyne and Pilbara grounds, with a 10kg fish a very good one and the biggest around 15kg and a bit over a metre. They are slow-growing and long-lived — a couple of decades is normal for the larger fish — and protogynous, maturing as females and changing to male with age, so a big rankin is an old male that took a long time to get there. That combination is the whole reason the demersal bag sits at 4 across all species and why release weights matter more here than the size of any individual fish.
Diet & Habitat
An ambush predator that sits in cover and inhales whatever swims past — small reef fish, squid, octopus and crabs. They hold on rubble bottom, broken reef and coral edges in roughly 30–100m, favouring the shoulders and corners of structure rather than the peaks, and they share that water with red emperor, spangled emperor and goldband snapper, which is why all four come up on the same paternoster rig. In WA they run from around Shark Bay north through the Gascoyne and Pilbara into Kimberley waters, with the charter fleets out of Coral Bay, Exmouth, Onslow and Dampier working the core of it.
WA Size & Bag Limits
| Minimum size | No minimum size |
|---|---|
| Bag limit | 4 (Gascoyne and North Coast bioregions) |
| Counts toward | Counts within the demersal scalefish total mixed daily bag of 4. No species-specific minimum applies — rankin cod sit in DPIRD's Rockcods group, which sets a minimum size only for goldspotted rockcod. A Recreational Fishing from Boat Licence is required when fishing from a powered boat. |
No species-specific minimum legal size (rankin cod sits in DPIRD's Rockcods group, which sets a minimum size only for goldspotted rockcod). Individual daily bag limit: 4 in the Gascoyne and North Coast bioregions where the species lives, taken within the demersal scalefish TOTAL mixed daily bag of 4. The West Coast boat-based demersal closure (south of Kalbarri) runs until Spring 2027, but the rankin cod fishery sits north of that line. A Recreational Fishing from Boat Licence (RFBL) is required when fishing from a powered boat.
Eating Quality
Excellent — firm, white, mild flesh that holds together on the grill, in a curry or under a batter without breaking up, and some of the cleaner-tasting grouper meat on the WA coast. Skin it rather than scaling it; the fillets are thick enough to cut into portions and cook like steaks. Fish in the 3–6kg range are the pick, giving usable fillet thickness without the coarser texture the big old males develop. Bleed at the gills and ice on capture — tropical reef fish deteriorate faster than they look, and a rankin left in a warm kill tank loses its edge within the hour. The cheeks are worth taking on the larger fish. Fillets freeze well vacuum-sealed for a couple of months, which suits a species you will often catch alongside a bag of reds.
Perth Tips
Rankin cod are a routine bonus when targeting reds — same rig, same depth, same grounds. Charters out of Coral Bay, Exmouth, Onslow and Dampier put them on the deck most trips through the cooler months. Keep a release weight on board and use it; rankin pulled from 80m don't recover unassisted.