The Hawkesbury basin is well known for its oyster farming operations. They are often seen from the highway or the train on the way to Sydney and help cater for the Aussie appetite for fresh seafood.
Recently a virus is affecting Pacific oysters in the Georges River, Parramatta River and Hawkesbury River causing a condition known as Pacific Oyster Mortality Syndrome or POMS for short. It hasn't been know to affect Sydney Rock oysters at this stage and there are no health implications for people. Oysters are killed within days of being infected and up to 100% of the population can be affected.
It was first detected in NSW in 2010 in the Georges River when farmers reported oyster deaths to DPI and the virus was subsequently identified. POMS has been detected in oyster populations after mortality has ceased indicating that survivors may act as carriers for the virus. Little is known about the virus life cycle and how it can be treated. All life stages are susceptible but juveniles are particularly vulnerable. Outbreaks tend to be affected by temperature. They tend to occur above 22°C but not below 16°C.
It's not known how POMS got to NSW. Since an outbreak in France in 2008 it has since been detected in UK, Ireland, Netherlands, Spain, Italy, Asia and NZ. There are movement controls and strict biosecurity conditions in place to prevent movement of oysters and gear from Georges and Hawkesbury Rivers and Brisbane Water to any other NSW waterway to reduce the risk of spreading the disease.
The public can help by reporting mortality outbreaks in wild Pacific Oyster populations to DPI Aquatic Biosecurity Unit on (02) 4982 1232. Maintain vigilance and ensure recreational boats and equipment are cleaned after using these waterways (especially before moving to another waterway) helps maintain the biosecurity protection. Make clean part of your routine!
This geocache is one of a series of Pest Watch geocaches focusing on the biosecurity of NSW, developed by the NSW Department of Primary Industries (DPI). These geocaches are designed to provide information to the public in an effort to protect the environment of NSW. DPI has a lead role in preventing, responding to and overseeing the recovery from invasion or spread of plant pests and diseases.
If you suspect the presence of an exotic plant disease or pest, or if you see unusual symptoms on your plants, you can report it to the Exotic Plant Pest Hotline on 1800 084 881. Further information on this and other biosecurity threats currently faced by NSW can be found on the DPI Biosecurity website www.dpi.nsw.gov.au/biosecurity.
Cache Details
From the carpark you can head towards a picnic table and a nice secluded area down towards the river. The cache is small so no room for swaps and you will need to bring a pen.