Marron

Cherax cainii

The marron (Cherax cainii), also known as the smooth marron, is a large freshwater crayfish in the family Parastacidae, endemic to southwestern Australia. Adults can reach up to 38 cm and over 2 kg, making them the third-largest freshwater crayfish species in the world. They have a robust body with large, smooth-edged claws and coloration varying from dark brown to olive-green, with some individuals displaying striking blue tones. Marron inhabit permanent freshwater rivers, streams, and dams at depths of 0-5 meters in southwestern Western Australia. They are omnivorous, feeding on decomposing plant material, algae, small invertebrates, and detritus. Marron require well-oxygenated water with adequate shelter such as submerged logs and undercut banks. They are an iconic Western Australian species, important both culturally and as an aquaculture product. Their impressive size and endemic status make encounters in clear Western Australian rivers a memorable freshwater diving experience.