Marron
Cherax cainii
Also known asWestern Australian marron · Cherax
Water parameters
Minimum tank: 300 L per individual at harvest size.
Feed and growth
- Feed protein
- 32% target
- Daily feed (warm)
- 1.50% of body weight
- Daily feed (cool)
- 0.60% of body weight
- Max density
- 25 g per litre
A 400 g adult eats about 6.0 g of feed per day at optimum. 10 fish at adult size: ~60 g daily.
Legality
Rules vary by jurisdiction and change over time. Verify with your local fisheries or wildlife authority before stocking.
| Jurisdiction | Status | Notes |
|---|---|---|
| Western Australia | legal | Native species in Western Australia; no permit required for personal aquaculture verified 2026-05-13 |
| South Australia | permit required | Translocation permit required outside native range verified 2026-05-13 |
| Victoria | permit required | verified 2026-05-13 |
| New South Wales | prohibited | verified 2026-05-13 |
Unlisted jurisdictions default to "check local regulations".
Origin and habitat
Cherax cainii, the smooth marron, is a freshwater crayfish native to the south-west of Western Australia, ranging roughly from Geraldton south and east to Esperance. It is the largest freshwater crayfish in Western Australia and the third largest in the world, behind only the giant Tasmanian crayfish (Astacopsis gouldi) and the Murray crayfish (Euastacus armatus), growing past 40 cm and 2 kg in exceptional animals, though culture stock is usually harvested at 60 to 150 grams. It lives in clear, well-oxygenated streams among woody debris and undercut banks. The closely related hairy marron, Cherax tenuimanus of the Margaret River, is a separate and critically endangered species; the smooth marron itself is listed as Least Concern. Marron are a prized food in Western Australia, with firm, sweet, lobster-like flesh, and farming of the species took off through the 1970s and expanded quickly in the late 1990s into a notable Western and South Australian industry.
Climate and outdoor ponds
- Climate
- temperate (handles seasonal swings)
- USDA zones
- 7–10 (winter low around -18°C or warmer)
- Heating needed
- no
- Cooling needed
- yes, if summer water exceeds upper tolerance
Care notes
A premium freshwater crayfish for temperate aquaponics with cool to mild water, best around 15–25°C and peaking near 22°C. Marron grow slowly next to tropical crustaceans, reaching 60–150 g in eighteen to twenty-four months on a crayfish pellet of about 28 to 35 percent protein, with feed conversion typical of crayfish, roughly 2 to 3. The reward is flavor and price, $30 to $80 per kilogram in Australian markets, so even small harvests pay. Temperature tolerance is moderate, about 8–28°C, but growth nearly stops below 15°C and the animal stresses above 28°C. Marron need good oxygen, above about 5 mg/L, and are less forgiving of low oxygen than warm-water crayfish such as red claw; overfeeding that crashes dissolved oxygen is a common cause of losses. Stock by bottom area at roughly five to ten per square metre, with shelter, lengths of pipe, stacked tile, or mesh bundles, to cut aggression and cannibalism during molting, and keep ammonia low since marron are fussier about water than yabbies or red claw. Juveniles come from Western Australian hatcheries. The species is legal to farm in Western Australia and, with permits, some other states, but interstate and international movement is regulated. Outside Australia marron are seldom available, and red claw crayfish or freshwater prawn are easier alternatives.