A sample of crabs, collected from the outer part of Bunbury Harbour, found more than 50 blue swimmer crabs that had developed the disease, which is caused by a naturally-occurring bacterium.
?A blue swimmer crab from Bunbury Harbour with bacterial shell disease.
The condition, which causes the shell to break down and lesions to form, is often found at low levels in crab populations. But the severity and high percentage of crabs affected in the outer Bunbury Harbour samples prompted further investigation.
So far, only crabs from Bunbury Harbour are showing high levels of this bacterial shell disease.
As a precaution, the Department of Health advises that recreational or commercial fishers should not collect or consume any crabs that are damaged or have shell lesions, or appear to be in poor health or condition, as they may be affected by bacterial pathogens or other agents which can affect human health.
Anyone who sees an affected crab in areas other than Bunbury Harbour is asked to take a photo if possible (but do not retain the crab), and report the find immediately to Fishwatch on 1800 815 507.
