Crayfish vs Lobster: What’s the Difference in WA?

There are really three different animals tangled up in “crayfish vs lobster” in WA.

Rock lobsters (saltwater, no big claws). These are the spiny lobsters — the western rock lobster (Panulirus cygnus) that drives the famous west-coast fishery, plus the tropical painted crayfish (Panulirus versicolor) and its relatives up north. Long spined antennae, a heavily armoured shell, and — crucially — no large pincer claws. This is the “cray” or “crayfish” almost every WA angler means.

True clawed lobsters (saltwater, big claws). The animal most people picture when they hear “lobster” — the Boston or American lobster, with two heavy front claws. These belong to a different family in the cold North Atlantic and are not found in WA waters. That’s the single biggest source of confusion: the lobster in the picture and the lobster on the WA reef look nothing alike.

Freshwater crayfish (freshwater, clawed). WA’s genuine crayfish — marron (Cherax cainii), plus the smaller gilgie and koonac. These live in south-west rivers, dams and weirs, have proper claws, and are the closest thing WA has to a textbook “crayfish”.

Habit, mostly. Western rock lobster has been “crayfish” or “cray” in WA vernacular for generations, long before anyone worried about scientific tidiness. It’s a rock lobster by biology and a crayfish by conversation. Fisheries paperwork and menus say “rock lobster”; the bloke pulling pots off Rottnest says “cray”.

It’s easier than the naming suggests.

• Big front claws? It’s either a true clawed lobster (not WA) or a freshwater crayfish — and fresh water means marron, gilgie or koonac.
• No big claws, long spiny antennae, salt water? That’s a rock lobster — western rock lobster down south, painted or ornate up north. The western rock lobster is reddish-brown on cool west-coast reef; the painted crayfish is banded blue-green and white on tropical reef.

Western rock lobster is a metro-and-mid-west reef catch — pot or free-dive only, no rod and line. The inshore reefs off Rottnest Island and the metro grounds out from Mindarie Marina fish well early in the season, with the mid-west grounds off Lancelin, Cervantes and Jurien Bay producing through summer.

Marron is a south-west freshwater catch, taken by drop net or snare — never on a rod. The reliable public-access waters are Wellington Dam, Waroona Dam and the rivers and dams around Pemberton. Gilgie and koonac share those waterways but rarely get targeted — more kids’ dip-net catch than dinner.

Painted crayfish and the other tropical rock lobsters are a far-north job, hand-collected or potted on shallow coral reef in the Pilbara and Kimberley.

This is where the terminology stops being academic — the two main “crayfish” of WA need two different licences.

Western rock lobster requires a Recreational Rock Lobster Licence — separate from any boat licence — and can only be taken by pot or by free-diving (no scuba, nets or spears). The minimum size is a 76mm carapace for the southern fishery, the daily bag limit is 8, and every lobster must be measured in the water and tagged before it leaves. Berried (egg-carrying) females go straight back.

Marron requires a separate Recreational Marron Licence and a short open season — typically a few weeks in midsummer, around January. They’re taken only by approved drop nets or snares, with a carapace size limit and tighter rules in designated trophy waters. Buy a marron gauge before you go; eyeballing the size is how people end up with a fine.

Both fisheries are actively patrolled, and the exact dates, sizes and bag limits shift between seasons — confirm the current numbers with the DPIRD recreational fishing rules before you set a pot or a net.