Outbreaks of Marteilia sydneyi in Sidney rock oysters and their relationship with environmental pH.
An experiment was designed to determine whether changes in environmental pH were responsible for outbreaks of Marteilia sydneyi, the cause of QX in Sydney rock oysters, Saccostrea commercialis. The relationship was suspected since outbreaks of the disease usually follow annual summer rainfall which has been associated with acidification of many rivers of which M. sydneyi is endemic. Experiments were carried out in the Pimpama River and in the mouth of the Brisbane river. Outbreaks of QX were recorded at each site, however monitored pH values showed no causal relationship between pH and outbreaks of M. sydneyi.