Sought-after blue marron demystified
These striking blue marron are found in the wild throughout the South West and Great Southern and have been a popular addition to lounge room aquariums for at least 30 years, but why are they blue?
The Great Southern Herald spoke with Department of Fisheries’ principal research scientist for freshwater fish production Craig Lawrence to learn more about these crustaceans.
Dr Lawrence said the bright blue hue of the marron is due to a genetic mutation but they are the same species as the common black and brown marron.
He said it was a simple recessive gene being expressed that gave the normally black or brown creatures their distinctive blue colouring.
“They used to be very, very rare until people started farming them,” he said. “If you mate two blue marron, you will get blue progeny but if you mate a black and a blue, you will get mainly black progeny and if you mate those progeny together, you will get some blues too.”
Dr Lawrence said the blue marron had been cultivated for the ornamental market as they fetched a good price from people wanting to use them in aquariums.
“But you wouldn’t really want to have blue marron in a commercial food marron farm,” he said. This is because the blue marron turn an orange colour rather than the bright red associated with cooked crayfish.
“Restaurants prefer the dark black or brown marron because they cook up a bright red,” Dr Lawrence said.
“It’s an amazing resource to have in WA and I think we should really appreciate. “Marron is the third largest freshwater crayfish in the world and overseas ... marron are really very highly regarded outside of Australia and I think we take our rather unique fish for granted.”
These blue marron were caught in the Great Southern.