19 Crown Road
Umina, NSW, 2257
May 5, 2015
The Hon. Niall Blair, MLC
Minister for Primary Industries, Minister for Land and Water.
NSW Department of Primary Industries
52 Martin Place
Sydney, NSW, 2000
Re: Permit to cultivate Pacific Oysters in the Hawkesbury River estuary system.
Dear Mr Blair,
I write to you today out of concern for my future and the future of the native oyster industry within the Brisbane Waters region. A friend of mine that farms oysters in the Hawkesbury River has bought to my attention your idea to start cultivating non-native Pacific oysters as a way to beat QX disease. I understand the thought behind the idea, as a farmer I can understand how hard it would be to lose my stock to a disease like QX however I’m concerned about whether this is the best solution and that it may result in further problems along the line.
As I’m sure you’re aware, QX disease is widespread. However, there are many instances where QX is yet to be found. My farm is located about 33Km from Hawkesbury River, in the Brisbane Waters catchment near Gosford. Currently QX disease has not affected my stock at all. Although at the moment the coast is clear I’m worried about my future and that of my business and family if QX is to eventually find me.
I’ve done some research into triploid Pacific oysters and have a few concerns about introducing them as a replacement for Sydney Rock Oysters.
1. Their ability (however slight) to reproduce.
2. Other diseases
3. Appearance and customer demand for local produce.
I’m aware that currently Pacific Oysters are being farmed for aquaculture in Port Stevens NSW without an issues. However elsewhere within NSW these oysters are considered to be a foreign pest and overseas there has been issues with this species. Have we not learnt our lesson with introducing “pests” into our ecosystems? Look at the Queensland Cain toad for example, they were introduced to help and combat a problem, only to become a bigger problem themselves. How can we be sure this will not happen with the Pacific oyster? I don’t believe one example in Port Stevens in enough to support an entire idea. Although their ability to reproduce is low it’s still a possibility. It may take years and years for them to reproduce enough to create a problem but what do we do then?
My next concern was that other diseases, other than QX may cause the exact same problem among the Pacific Oyster populations. I’ve done some research and found an article about mass mortality in commercially farmed Pacific oysters in the Hawkesbury River from a disease called Ostreid herpesvirus -1. This seems to be fixing a short term problem only to deal with it again later.
My final concern was the appearance of the Pacific Oyster in comparison to the Sydney Rock oyster. I read another article that warned that Pacific oysters undergo changes to the shape of their shell, which makes them less attractive.
The Brisbane Water Oyster Festival is held in November each year at the Ettalong Beach waterfront. The festival allows local oyster farmers to sell their oysters. It is extremely important to me to have the best produce for my customers at this event in order to boost my income and support my family and business.
I believe that with further research there may be other methods of saving the Sydney Rock oysters from QX disease. I request look further into the matter before making any firm decisions that may affect the oyster industry for everyone, not just those affected by QX disease.
Thank you and regards,
Sydney Rock oyster farmer from Brisbane Waters.
Bishop, M. J., Krassoi, F. R., McPherson, R. G., Brown, K. R., Summerhayes, S. A., Wilkie, E. M., and O’Connor, W. A. (2010). Change in wild-oyster assemblages of Port Stephens, NSW, Australia, since commencement of non-native Pacific oyster (Crassostrea gigas) aquaculture. Marine and Freshwater Research 61, 714–723.
Green, T., Raftos, D., O’Connor, W., Adlard, R., Barnes, A. (2011). Prevention Strategies for QX Disease (Marteilia sydneyi) of Sydney Rock Oysters (Saccostrea glomerata)
Journal of Shellfish Research, 30, 47-53.
Paul-Pont, I., Evans, O., Dhand, N., Rubio, A., Coad, P., Whittington, R. (2014) Descriptive epidemiology of mass mortality due to Ostreid herpesvirus-1 (OsHV-1) in commercially farmed Pacific oysters (Crassostrea gigas) in the Hawkesbury River estuary, Australia. Aquaculture, 422, 146-159.