Razorfish (Razorshell)
Shore / Sand flatsIn WA, 'razorfish' is not a fish at all — it's the razor shell or pen shell, a large fan-shaped bivalve (Pinna bicolor) that lives buried point-down in seagrass and sand flats. Gathered by hand on the shallow flats at low tide for its sweet adductor muscle, and a popular feed and bait around Cockburn Sound and Shark Bay. A gathered shellfish, managed under the molluscs/razorshell rules.
Overview
Worth clearing up first: in Western Australia 'razorfish' (also razor shell or razor clam) is not a finfish at all — it's the pen shell, a large triangular bivalve (Pinna bicolor and relatives, Family Pinnidae) that lives buried point-first in seagrass meadows and sandy flats, with the broad fan of the shell protruding from the bottom. They're gathered by hand on the shallow flats at low tide, prized for the sweet scallop-like adductor muscle inside, and they're a long-standing feed and bait source on the flats of Cockburn Sound, the Peel-Harvey, Shark Bay and similar sheltered waters. So this is a gathering activity, not angling — you wade the flats and collect them, you don't catch them on a line. Take care: the thin shell edges are sharp (hence the name) and the exposed shells can cut bare feet.
Identification
Razor shell, razorshell, pen shell, razor clam
Start with what it isn't: razorfish is not a fish. It's a large bivalve mollusc — the pen shell, Pinna bicolor — that lives buried point-down in the bottom with the broad, fan-shaped end of the shell standing up out of the sand or seagrass. The shell is thin, brittle, roughly triangular and olive to dark brown, often so fouled with weed and growth that it reads as a piece of rubbish until you look properly. You're not identifying this one at the end of a line; you're spotting it on the flats. The only real name clash is with the northern-hemisphere razor clam, a long narrow shell and an entirely different animal.
How to Catch
N/A — razorfish are gathered by hand, not caught on bait. (The muscle itself makes excellent bait for whiting, bream and other fish.)
N/A
No rig — razorfish are collected by hand on the flats. A glove and a knife or shucking tool to cut the adductor muscle, plus a bag or bucket, are all that's needed. Some gatherers cut the muscle in situ and take only the meat; others collect whole shells to shuck on shore.
Wade the shallow seagrass and sand flats at low tide and look for the protruding fan-shaped shells standing up out of the bottom. Reach down and cut the adductor muscle with a knife, or gently work the shell free. Move quietly over the flats — and watch your footing, as the buried shells are sharp underfoot. A rising day with clear, calm shallow water makes spotting them far easier. Collect only what you'll use.
Gathered year-round, best on the low tides that expose or shallow-up the flats, and in clear, calm conditions that make the shells easy to spot. Daytime low tides over the seagrass meadows are ideal. Warm, settled weather suits wading the flats.
Shell commonly 20–40cm long
Year-round
Size & Growth
Shells commonly run 20–40cm along the long axis, with the biggest on good Cockburn Sound and Shark Bay seagrass going larger again. What you're after is the adductor muscle inside — the round white 'scallop' that holds the shell shut — which in a decent razorfish is roughly the size of a large scallop, a few centimetres across. A bigger shell doesn't always mean a bigger or better muscle, and very large old shells are often thin and heavily fouled. They grow slowly and stay put for years, so a bed you clean out doesn't refill quickly. Good argument for taking only what you'll eat.
Diet & Habitat
Razorfish are filter feeders. They sit anchored point-first in the sediment by fine byssal threads, siphoning plankton and organic matter from the water column, which is why they favour sheltered, gently flowing water rather than surf. Look for them across shallow seagrass meadows and the adjacent sand flats, typically in knee- to chest-deep water and often scattered in loose beds. In WA the classic grounds are Cockburn Sound and the Warnbro and Shoalwater flats, the Peel-Harvey estuary, Geographe Bay and the vast seagrass meadows of Shark Bay. They need clear, stable, seagrass-backed water, so the health of a razorfish bed tracks the seagrass around it.
WA Size & Bag Limits
| Minimum size | No minimum size |
|---|---|
| Bag limit | 20 |
| Counts toward | Managed as a gathered mollusc rather than a finfish, so it sits outside the finfish mixed bags. Rules differ for collection from a boat and by area. |
Razorfish are razorshells (Family Pinnidae), managed as a gathered mollusc, not as a finfish: no minimum size, and a daily/possession limit of 20 (as listed for razorshells in the WA molluscs and invertebrates rules). A separate licence is not generally required for hand-gathering from the shore, but rules differ for collection from a boat and by area.
Eating Quality
Very good — the white adductor muscle eats much like a scallop: sweet, tender and clean, with a slightly firmer bite. The rest of the animal is usually discarded; the muscle is the prize. Sear it hard and fast in butter, a minute a side at most — it turns rubbery the moment it's overdone — or slice it thin through pasta, chowder or a seafood stir-fry. Big muscles from large shells can be cut through the middle so they cook evenly. Rinse the grit off thoroughly first, and use them the day you collect them; they don't hold and they don't freeze, going watery and tough on thawing. If you gather a surplus, the muscle makes a top bait for whiting and bream — better than most of what you'll buy.
Perth Tips
Cockburn Sound, the Peel-Harvey flats, and the Shark Bay seagrass meadows are classic razorfish grounds. Wear sturdy footwear or booties — the buried and discarded shells are genuinely sharp and cut bare feet easily. Take only what you'll eat, and don't leave broken shells scattered on popular flats. The muscle also makes a top bait for whiting and bream if you gather a surplus.