As the critically endangered hairy marron is now found only in three pools in the Margaret River, a captive breeding program was established at the Pemberton Freshwater Research Centre, with the goal of releasing captive-bred marron back into the wild.
Fisheries scientists have years of experience breeding Australian freshwater crayfish, including yabbies, redclaw and smooth marron. However, breeding the hairy marron is proving to be a challenge.
Given the right conditions and facilities, freshwater crayfish usually reproduce easily. Marron are also highly fertile, producing hundreds of juveniles. So even with a low percentage of females ‘berrying up’ (producing fertilised eggs), the program should easily and quickly be able to produce hundreds, if not thousands of hairy marron for restocking…but things have not gone exactly to plan.
In 2013, 15 berried females produced about 200 juveniles and expectations were high for 2014. Only five females berried that year, but we were still able to produce more than 150 juveniles. With good numbers of healthy animals, all the signs were positive for 2015.
However, only two females berried properly. Though this may still produce another hundred or so juveniles, it is not the increase in numbers we had been hoping for. Despite this, our hairy marron ponds are at about 50 per cent capacity and their numbers are still slowly increasing.
With wild populations still under threat, we will be trialling some new techniques to improve our success rate and aim to have enough animals for a release into the wild in 2017.