There are four major types of freshwater crayfish in Western Australia.
A freshwater crayfish that lives in rivers and dams through out the state's south west. It is excellent eating but you must get a fishing license before catching any and size limits are enforced.
Marron are one of the largest freshwater crayfish on Earth and naturally ranged in freshwater rivers from Harvey to Albany. They have now been introduced to rivers that range from Hutt River to Esperance.
Sadly the salination of some rivers has seen the marron populations that once inhabited them destroyed.
Unlike yabbys and koonacs (that only have 4 'keels' on their heads, marron have 5 'keels'. They vary in colour from black to cobalt blue.
There are two types of marron in W.A., the smooth and the hairy. The hairy marron are restricted to the upper reaches of the Margaret River and are now protected.
Marron can grow to over 380mm.
Get more information on current size limits, licenses and open season from the Dept. of Fisheries website.
Smooth and hairy marron - Picture from the Department of Fisheries www.fish.wa.gov.au
Another type of freshwater cray called a Yabby can also be caught in rivers and dams. Yabbys are much smaller than Marron and don?t have the same limits to size or season. There are two types of Yabby in W.A. Cherax albidus and Cherax destructor.
Colour varies from brown to black and they rarely grow longer than 130mm.
Because they are introduced and because of their ability to out breed the marron and because they also transmit diseases, yabbys are regarded as a pest species and if caught should not be thrown back.
Yabby - Picture from the Department of Fisheries www.fish.wa.gov.au
Cherax plebejus and C. glaber
Usually found further inland than the marron, the koonac is a resident of farm dams and seasonal rivers. Koonacs have the ability to dig deep burrows and remain there for months at a time until rivers and dams re-fill.
They can grow up to 200mm in length and are usually blue-black or brown-black in colour.
Koonac - Picture from the Department of Fisheries www.fish.wa.gov.au
Cherax quinquecarinatus and C.crassimanus
Gilgies are common through out the south west and can be found in streams and dams. Like marron, gilgies have 5 keels on their heads but they only have two pairs of small spines on the rostrum and none on the telson. They can grow up to 130mm ad are usually black-brown to light brown in colour.
Gilgie - Picture from the Department of Fisheries www.fish.wa.gov.au