This is an article I previously published in the Canberra Fisherman's Club's February 2018 Newsletter. I have reproduced it here as part of my series of articles on the proposed use of the Cyprinid herpesvirus (CyHV3) or (also known as the Carp Herpes Virus or Koi Herpes Virus) to reduce the Carp population in Australia's inland waterways. Please note that as this article was published in February 2018, the information and views I expressed in this article are based on my understanding and knowledge of the issues at that point in time.
In the May 2016 General Meeting, the members voted in favour of the Club supporting the release of Cyprinid Herpes Virus (CyHV3) to reduce the Carp population in Australia provided the Government adequately funds the clean-up of waterways of dead and dying Carp, habitat restoration and restocking of native fish.
To find out more about the possible release of CyHV3, Brian Hetherington from the ACT Fly Fishers, Jason Middleton from Canberra Anglers Association, and I attended a stakeholder workshop on 19 February 2018 co-hosted by the National Carp Control Plan (Matt Barkwick) and the ACT Government (Allison McInnes). The purpose of the workshop was to give an update on the latest news on the possible release of CyHV3 and to seek stakeholder feedback on a range of issues around the release. Peter Beutel from the National Capital Authority and Matt Beitzel from the ACT Government also gave presentations.
The NCCP is a large program of research and consultation to identify a smart, safe, effective and integrated suite of measures to control carp impacts. This includes exploring the potential use of CyHV3 as a biocontrol. Part of the NCCP's work includes stakeholder consultations, such as the workshop we attended on 19 February 2018.
At the end of 2018, the NCCP will make recommendations based on the evidence gained during this process, in a document entitled 'The National Carp Control Plan'. The release of the virus won't take place until it is approved by the Federal Government, and by each of the State and Territory governments in the Murray Darling Catchment.
Matt Beitzel talking about the latest ACT Carp numbers at the Stakeholder workshop (Photo by Jason Middleton, Canberra Anglers Association).
I am still processing all the information from the workshop but I'm happy to share the notes of my meeting if you are interested. A copy of my handwritten notes are now available at the end of this article. There's probably a lot you already know about the Carp and the virus in these notes. For me, the highlights of the workshop were:
- Matt Barwick discussed what methods have already been tried to reduce Carp populations and gave reasons why they all failed. This now leaves biological control as the only means by which we can reduce the Carp population on a continental scale.
- There is still a lot of research being done by the CSIRO, Charles Sturt University, University of Adelaide, University of Western Australia, Curtin University on different aspects of the impact of a big fish kill on our waterways, the clean-up, and disposal of dead carp.
- There won't be a 100% clean-up of our waterways from the dead carp, but the following areas will be prioritised:
- Urban areas
- Town waters
- High recreation areas
- High accumulation areas (such as weirs)
- Threatened fish habitats
- Other sensitive areas (my words as I can't remember what Matt Barwick called these bits of waterways).
- Therefore, the areas of the clean-up will be very small.
- Habitat restoration and restocking of native fish is outside the scope of the National Carp Control Plan.
- The plan for a staged deployment of the Carp Virus appeared credible but there is a risk of idiots being too impatient and deliberately transferring sick carp into catchment areas before their scheduled deployment. This will create a few problems and there needs to be a contingency plan to deal with this.
- The window of opportunity for deployment of the virus into the ACT's waterways will be narrower than the NSW catchments as ACT waterways are a lot colder.
Matt Beitzel estimated that there are about 600 to 900 kg of Carp per hectare in Lake Burley Griffin. In fact, this is down from 1200 kg per hectare in 2012. Matt thinks this is because our waterways in the ACT cannot support any more Carp. I spoke with Matt Barwick afterwards, he was also of the view that the Carp population probably can't get any worse as the Murray Darling Catchment cannot support any more fish. On the flip side, he said this means there is little scope for our native fish population to recover unless Carp numbers are reduced.
My thoughts from the workshop are that I'm comfortable that the case for releasing the virus is stronger and that the decision on whether to release virus is not being done in a cavalier manner. My main concern is that habitat restoration and fish restocking falls outside the scope of the National Carp Control Plan. If the release of the virus is approved, I believe we need to pressure on the State and Territory governments to use this opportunity to conduct habitat restoration work in our waterways and to restock native fish.
I think for me, I'd like to do some reading up on existing literature on fish kills and the impact on waterways when the dead fish are simply left to decompose where they are. This will probably help people decide whether they are comfortable with the idea that maybe only 5% of waterways are going to be cleaned up after the Carp virus is released. If I get around to this in my copious free time, then I'll add this to the Club's FAQ on the Carp virus.
I think we also need to explore whether we hold off on fish stocking activities until after the Carp virus is released so that we don't waste our money on fingerlings that will only die when the virus is released.
Getting rid of the Carp from our waterways won't just benefit our native fish. Removing Carp from our waterways is also expected to revive our aquatic bird population. Since writing this article, it appears that scientists now expect there will be a short to medium term decline in the population of aquatic birds that rely on Carp for food.
For those interested in reading my handwritten notes from the workshop, you can download them: Handwritten notes from the National Carp Control Plan stakeholder workshop, Canberra, 19 February 2018 (pdf).
Please note the notes are incomplete and you should seek clarification from me if you have any questions about the notes.
Since I published this article in the February 2018 CFC Newsletter, Matt Barwick stepped down as the NCCP Coordinator, and replaced by Jamie Allnut. Around the same time, the media reported concerns being expressed by scientists about the proposed release of the CyHV3 virus, and the Ausrtralian Government extended the delivery date for the National Carp Control Plan to allow further research. At this point, I am sorry to say I had lost interest in keeping up to date with the latest news on the NCCP, and never got around to updating the Carp Virus FAQ. That was until I received a request in August 2018 to participate in a stakeholder survey on the topic conducted by the University of Canberra. I have since reviewed a further 70 articles, NCCP Progress Reports, Discussion Papers and Scientific Papers. I am still digesting the contents of this material, but will publish a further article providing an overview of the latest research and other findings.