Oyster mortality information
Why report oyster mortality?
A number of oyster diseases pose a significant threat to the NSW oyster industry, these diseases are listed as declared under the Fisheries Management (Aquaculture) Regulation 2007. These diseases include QX disease (caused by Marteilia sydneyi) and Winter mortality (caused by Bonamia (Mikrocytos) roughleyi).
It is a condition of every Class A Aquaculture Permit:
The permit holder must report to the local fisheries office the details of any suspected disease or unusual mortality affecting the fish or marine vegetation on the leased area, as soon as practical, and no later than 48-hours from becoming aware of any such occurrence.
Protocol for reporting oyster mortality:
In the event that a significant oyster disease/mortality is observed:
1. Within 48 hours phone either:
- 24 hour hotline 1800 043 536
- your local NSW DPI Fisheries office, and ask to speak to a Fisheries Officer.
- Manager Aquatic Biosecurity & Risk Management (02) 4982 1232
2. Complete a NSW DPI Fisheries Veterinary Laboratory Specimen Advice form and a Oyster Mortality Report form. Accurate information is required as it will assist in determining the cause of the disease event. Please provide comments on any suspected cause or unusual environmental conditions.
3. Collect and package the samples as directed by NSW DPI.
4. Attach these forms, taped in a plastic bag, to the outside of the container in which the samples are being sent to the laboratory.
5. Arrange freight of samples to laboratory or seek assistance from NSW DPI or your local fisheries officer.
6. Await laboratory diagnosis. While awaiting this result stock movements should be minimised, in case you may be spreading an infectious agent (eg virus, new parasite).
Oyster mortality is often due to predation or environmental effects such as heat or freshwater input and may not be the result of a disease. Even so, it is important that all events of unusual mortality are reported. Why? Causes of disease can go undetected to the naked eye.