Where and when to catch Blue Threadfin in Queensland: the QLD season, the spots in our guide that hold them, and where to find QLD's current size and possession limits.
Called Blue Salmon on our Western Australian guide.
Up to 1.2m, commonly 40–70cm (captures to ~3kg common)
QLD season
Year-round (best Mar–Aug)
QLD spots
3
QLD Size & Possession Limits
QLD limits for Blue Threadfin are set by Fisheries Queensland and change from time to time, so we link them rather than copy them.
Check Fisheries Queensland's limits before you fish.
Western Australian limits don't apply in Queensland.
Live prawn, mullet, herring, fresh mullet fillet, strip baits
Lures
Soft plastics on 1/4–3/8oz jigheads, soft vibes, small suspending hardbodies, slow-rolled paddle-tails
Rigs
Light to medium estuarine spin gear — running sinker rig with a 3/0–4/0 circle hook and 20–30lb fluorocarbon leader, with just enough lead to hold in the wash or current. Unweighted live baits work well on the run-in. Keep drag moderate; the soft mouth tears under heavy load.
Technique
Cast plastics and small hardbodies into beach gutters and along creek-mouth sandbanks, working them slowly with the current on the run-in tide. On bait, drift a prawn or mullet through the wash and feed line on the take before lifting into the fish. Blue salmon often hold where freshwater or a creek meets the sea — fish those edges at change of light. Slide or net them rather than lifting by the line.
Best Time
Through autumn and winter in Queensland's rivers and creek mouths. The last hour of the run-in before high and the first of the run-out are prime, and dawn and dusk outproduce the middle of the day.
From the Boyne River and Tannum Sands north, including Gladstone, the Calliope and Fitzroy rivers and the Capricorn Coast creeks, this is crocodile country: stay back from the water's edge, don't wade, and clean fish away from the water. Be Crocwise.
Identification
Also known asBlue threadfin, threadie, Cooktown salmon, bluey
A slim silver fish with a blue-green sheen, a blunt fleshy snout overhanging an underslung mouth, and small eyes — plus the family's odd party trick: separate free filaments hanging below the pectoral fin, used to feel for food in dirty water. Blue threadfin have four of them, which is what tetradactylum means. King threadfin (Polydactylus macrochir) have five, a longer and more sloping head, and grow far bigger. The two are caught in the same water under different limits, so counting filaments is worth the ten seconds. Neither is any kind of salmon.
Size & Growth
Most blue salmon off northern beaches and creek mouths are 40–70 cm and one to three kilos; a fish over 80 cm is a very good one, and the maximum runs to about 1.2 m. They grow quickly and are relatively short-lived compared with the reef fish caught nearby. Like king threadfin they change sex with age — fish start as males and the larger individuals are females — so the better fish in a school are generally the older ones. In practice a session produces numbers of similar-sized fish, because they school tightly by year class.
Eating Quality
Excellent — among the better eating fish of the tropical north, and arguably better than its bigger cousin. The flesh is white, moist and mild with a fine, soft flake, at its best simply pan-fried or grilled with the skin on, or crumbed. There is little oil in it, so it dries out if you cook it hard; take it off the heat early. Smaller and mid-sized fish are the pick, since big blue salmon and big king threadfin both coarsen. The flesh is soft to begin with and gets softer in heat, so bleed on capture and get it into ice immediately — a fish left in a hot boat is a fish for the bin. It freezes only fairly, losing texture within a month or so, which is a good reason to keep what you will eat and let the rest go.