King Threadfin Salmon

Surf / Estuary
Polydactylus macrochir

Large inshore predator of WA's North Coast — Eighty Mile Beach, Cambridge Gulf and the Pilbara estuaries are the headline waters. Not a true salmon despite the common name; a threadfin closer in habits to a mulloway, hunting beach gutters and creek mouths on the rising tide. Soft mouth, easy to bust off.

Overview

King threadfin are one of the great beach and estuary species of tropical WA — long-bodied, silver, with the distinctive trailing pectoral filaments that give the family its name. They patrol surf gutters, sand flats and creek mouths from the Pilbara through Eighty Mile Beach and into the Kimberley, hunting prawn, mullet and small baitfish on the run-in tide. Eighty Mile Beach is the iconic shore-based fishery, with Wyndham and the Cambridge Gulf creeks producing fish from boats. They have notably soft mouths, so a soft strike and steady pressure beat a hard hookset. Often caught alongside blue threadfin in the same waters.

How to Catch
Best baits

Live mullet, prawn, fresh mullet fillet, herring, strip baits

Lures

Soft plastics on 1/4–1/2oz jigheads, suspending hardbodies, soft vibes, slow-rolled paddle-tail plastics

Rigs

Running sinker rig with a 4/0–5/0 circle hook and 30–40lb fluorocarbon leader on the beach, with enough lead to hold in the surf. From a boat or creek bank, a lighter unweighted live-bait rig works well on the run-in tide. Avoid heavy drag — soft mouths tear out under load.

Technique

On Eighty Mile Beach, find a deeper gutter close to the sand and fish baits or plastics across the rising tide. In the creeks, cast plastics and hardbodies into the run-out at change of light, working them slowly along the sandbank edges. Keep drag moderate and pressure steady once hooked — they'll often head back into the wash, which is fine if you don't over-tighten. Use a long-handled net or a slide on the beach; lifting them by the line will tear the hook free.

Best time

April through November is prime, covering the dry-season tourist window when the beaches and estuaries are fishable. Run-in tides in the last hour before high are the standout window, with the first of the run-out also productive. Dawn and dusk consistently outproduce midday.

Size

Up to 1.5m and 20kg, commonly 60–90cm

Peak season

Apr–Nov (dry season peak)

Eating quality

Excellent — moist white flesh, mild flavour, holds together well when grilled or pan-fried. Bleed and ice on capture in the tropical heat. Considered one of the better eating fish of the North Coast, on a par with mulloway.

Regulations (WA)

Bag limit: 2 (within the threadfin combined daily limit). Minimum size: 60cm. Possession limit applies. Always check current DPIRD rules — regulations may change.

Perth Tips

Eighty Mile Beach Caravan Park is the obvious base for shore-based threadfin fishing, with the run-in tides on the new and full moons producing the best of it. Wyndham and Kununurra charters target threadfin alongside barramundi in the Cambridge Gulf creeks. Don't over-strike — feed line briefly on the take, then lift into the fish.

Where to Catch King Threadfin Salmon