Primary Industries Minister Tim Mulherin has tabled in Parliament this morning the first interim report into the two-headed fish mystery at Noosa's Sunland Fish Hatchery, saying no definitive diagnosis has been found.
The Noosa Fish Health Investigation Taskforce has identified six separate syndromes relating to fish health at the Sunland Fish Hatchery.
Syndrome one refers to sudden deaths of multiple species between November 2005 and January 2006.
According to a statement from Mr Mulherin, it seems the hatchery owner and adjacent farmer at that time suspected that a spray event was involved.
In the absence of any samples to test or other material that can be investigated, the Scientific Sub-committee accepts contamination from a spray event is a plausible explanation.
Since that time there has been a change of management at the Macadamia farm.
Syndrome two refers to sudden deaths of silver and golden perch in October 2007.
The report states there is insufficient information available to explain this event.
Syndrome three refers to spinning juvenile silver and golden perch in October 2007 and October 2008 and syndrome four refers to deformities of silver and golden perch in February 2008.
In both cases the fish benefited from treatment with atropine which counteracts organo-phosphate and carbamate compounds.
The Sub-committee accepts that these chemicals may have played a part but the source and specific chemicals are not determined.
Syndrome five has drawn the most attention. In July 2008 four Australian Bass females produced deformed larvae including many with two heads.
These females were sourced from the Noosa River and spawned in a shed protected from spray drift.
At this point no explanation can be provided and investigations continue.
Syndrome six refers to the sudden death of silver perch in December 2008.
Again there is no definitive explanation.
Multiple factors including gill fluke infestation, chemicals, water temperature, or oxygen levels may be to blame.
"The Taskforce acknowledges that not finding a chemical does not rule out possible impact from a chemical," Mr Mulherin said.
"Two samples have tested positive for chemical contamination.
"The insecticide Cypermethrin was found in one fish feed sample (at 0.001 mg per kg).
"And as I reported last month low levels of agricultural chemicals Carbendazim, Atrazine and Metolachlor were found in Cooloothin Creek about 2 kilometres downstream from the farm.
"This is a complex investigation with no simple answers.
"Consequently it should be no surprise that there are differences of opinion regarding this matter.
"Some within the task force believe the report does not go far enough in identifying chemicals as the cause of the problems, but overall the consensus is that it is not possible to provide a definitive opinion on the cause at this stage.
"The overall assessment of the Sunland Fish Hatchery was that it was an effective producer of native fish species for Queensland and at the time of the inspection no significant husbandry, feed, genetic, infrastructure or staffing issues could be implicated in the fish kills and abnormalities experienced.
"The overall assessment of the neighbouring macadamia farm is that chemicals have been used legally and in accordance with label instructions.
"Currently the farm is considered to be operating under industry best practice guidelines."
Another interim report is expected in September with the final report due next February.
The next phase of the investigation will involve: finalising a review of available literature; determining if any experimentation or additional sampling or testing is possible or required; and having clear procedures and protocols in place by July for dealing with any future events (in preparation for breeding activities at the hatchery and spraying season on the adjacent macadamia farm).
* The first interim report will be available on the Queensland Primary Industries and Fisheries website.
Email a friend