Earlier this year, the Victorian Murray Cod Reference Group was invited to comment on a range of changes that DEPI (Department of Environment and Primary Industries) is currently seeking public comment on. These changes are a dramatic departure from historic management methods, and to some people, may seem totally foreign.
While I was not part of the reference group, I did have the opportunity to ask Anthony Forster (Manager – Inland Fisheries) from Fisheries Victoria a range of questions about the proposed changes. I will say before you read this that after listening to the answers I am an advocate for these changes. I see it as a sensible use of available science to improve regulations to enhance fish populations and give those wanting to take a cod an opportunity to do just that. So let’s learn more about what’s proposed.
Q: Anthony, can you provide our readers with a list of the proposed changes?
Currently in Victoria, recreational fishers can take Murray cod above a minimum size of 60cm and below a maximum size of 100cm. A bag limit of 2 Murray cod per day applies.
Fisheries Victoria is proposing to introduce a revised minimum size for Murray cod of 50cm and a maximum size of 70cm, in all waters. We are also proposing a bag limit of two cod per day for lakes and impoundments and 1 cod per day in rivers.
Q: Dropping the size limit to 50cm seems like a big departure from all the fuss made about protecting the ability of a fish to breed once when the size limit was raised to 60cm. Can you elaborate on this please?
You’re right Stephen. For a long time, fisheries managers set minimum sizes that would afford a young Murray cod the opportunity to breed at least once before it could be harvested. That’s why, as we learned more about size and age at maturity, the minimum size for Murray cod increased a number of times e.g. in 1975 (50cm minimum size) and in 2009 (60cm minimum size). This approach assumes early maturing Murray cod (e.g. under 60cm) successfully breed in their first season however this may not be the case.
From hatchery experience, we know that Murray cod greater than 70cm are more effective breeders because they are more experienced and yield more and larger eggs. For example, a first maturing female Murray cod of 53 cm will produce around 10,000 eggs, compared with 90,000 eggs for a 100cm fish. For wild stocks of many fish species around the world, it’s now been shown that the large, older females contribute proportionally the most to raising the next generation.
Q: A slot limit is an interesting management tool, how did you arrive at a slot limit of 50-70cm?
During 2012, in collaboration with researchers at the Arthur Rylah Institute and the University of Florida, Fisheries Victoria gathered together decades of Murray cod population data and tested a number of bag and size limit scenarios using two independent Murray cod fish population models. The results clearly showed that narrower slot limits e.g. 50 to 70cm, were far superior in protecting breeding fish and rebuilding Murray cod numbers than current size limits.
We have also had feedback from recreational fishers that they were more comfortable in taking a smaller, immature Murray cod for the table than a larger, more important breeding fish. Also, smaller Murray cod are less fatty and more palatable than larger Murray cod.
Q: Reducing river bag limits to 1 fish will create some waves within the river fishing community that likes to keep a couple of fish. How was the proposal to reduce the bag limit in rivers reached?
Recreational fishing pressure has altered the natural size distribution of Murray cod, such that there is a peak in the abundance of cod just below the legal size of 60cm. Although few fishers currently take their bag limit of 2 Murray cod a day, there was concern that a pulse of fish between 50 and 60cm could be harvested soon after the introduction of a new 50 to 70cm slot limit. A bag limit of 1 Murray cod a day will moderate this initial take and, in the longer term, improve Murray cod breeding success in rivers. Recreational fishers we spoke to felt that, because Murray cod of 50 to 70cm are likely to weigh between 2 and 7 kilograms, this represents a reasonable daily take for the purposes of a meal.
Q: You talk about scientific modelling and how these proposed changes will improve outcomes for Murray cod populations, what exactly do you mean by improve outcomes?
The results of our fish modelling analyses strongly indicated that over a 15 year time-frame, by adopting the 50-70cm slot limit scenario, we might look forward to a 42% increase in Murray cod sustainability, a 146% increase in the number of trophy fish and a 12% increase in the number of fish available to harvest.
Q: So your modelling suggests there will be more Murray cod, does this mean anglers, in years to come, can expect to see more Murray cod on their line?
The modelling predicts recreational fishers will catch more Murray cod with a lot more larger Murray cod being encounter (and released) in the future.
Q: I note that the bag limit in lakes remains the same, why is that?
Because Murray cod are less likely to breed in lakes than in rivers. Victorian lakes and impoundments are primarily managed as stocked fisheries. For example, one million Murray cod were stocked into Lake Eildon over a recent three year period.
Q: So stocked fish are there to be taken by anglers, while wild fish are more protected? Can you elaborate further on this?
Yes. While we encourage Murray cod fishing in rivers and lakes, rivers experience more fishing pressure and these Murray cod are more vulnerable to harvest. By developing strong and viable lake fisheries, we are also diverting fishing pressure away from critical breeding populations of Murray cod in rivers.
Q: The reference group were briefed on the proposed changes and given access to some of the science behind the decisions. What did they think of the proposals?
The Murray cod reference group included some of Australia’s most experienced Murray cod fishers and advocates. After a detailed explanation of the science behind the proposal the group was supportive of the proposed changes.
Q: Traditionally, reference groups are made up of government friendly advocates, but this focus group was different. Can you explain how participants were selected?
Because we wanted to road test the science with recreational fishers, we invited a wide cross section of representative and independent fishers who brought to the table a variety of fishing methods, opinions and perspectives. We also invited a few fishing journalists who write about cod fishing to help us communicate our messages to the wider fisher audience.
So with all of that information, I hope you can come up with some of your own thoughts on the proposals. There is a limited time in which you can have your say due to our publication deadlines, however, as you read this there will be around five weeks left to comment. I know I’ll be commenting and I hope you will too.
I love fishing for Murray cod and regulations that might allow me the chance to tangle with more cod, keep one that will not impact on the population too much and know that all those big beautiful green fish are protected, seems like a good choice. Ultimately we recreational anglers will sway decisions by input, so now’s the time to let Fisheries Victoria know what you think.
How to get involved
Fisheries Victoria is providing a 60 day period of consultation and encourage recreational fishers to submit their feedback in writing about the proposal.
For more information about this proposal, including a consultation paper, video presentation and details of a public forum, please visit the DEPI website at www.depi.vic.gov.au/murraycodslots .
Proposed Regulation Snapshot
|Bag Limit River:||1 (in possession)|
|Bag Limit Lakes:||2 (in possession)|
|Closed Season:||Sep1 – Nov 30 inclusive|
Murray cod slot lengths
The science and projected benefits of applying slot length regulations to Murray cod is hard to ignore. And while I like and support the idea, I also understand that nothing regarding these fish is ever simple. I wrestle with what I have seen on the water in real time fishing as opposed to long term benefits and wonder on how the two will marry.
The projected increase in larger fish will provide an undeniable boost in breeding terms and angler satisfaction. At the same time what of the larger fish that refuses to swim? Should it be left to float loading another bullet in the barrel for those who already question our sport? As I said nothing regarding these fish is ever simple other than the fact that improving their stocks is something that we should all have a say in.
Some Focus Group Comment
I took the time to ask several of our writers who were part of the focus group what they thought of the proposals. Below are their thoughts on the changes.
Robbie has written for V&TFM for over 8 years and loves his cod fishing in and around Wangaratta. He also visits lakes such as Eildon and Mulwala, but his passion is shore-based fishing with lures in a total catch and release mode.
“At first I was sceptical about the new slot limits. After speaking to senior fisheries managers and scientists, and viewing the scientific evidence including growth rates, maturity sizes and seeing results from similar slot limits overseas I am now very excited about this proposal.
Anglers who wish to keep a fish will find it easier to catch a legal fish, and sportfishers who practice catch and release will win with a larger number of Murray cod in years to come.
Under the new proposed slot limits Murray cod will be protected for a much larger period of their life span than they currently are.”
Known widely as CodMac, Rod Mackenzie is certainly one of the leaders in the recreational cod fishing world. He has popularised and showcased big cod fishing in cooler water and his passion for these big fish, their welfare and fishing for them is unquestioned.
Roger is one of the most successful guides for Murray cod in the country and has an intimate knowledge of Murray cod, their habits and how to catch them. His livelihood depends on good Murray cod stocks so he protects that with great vigour encouraging catch and release of all Murray cod caught on tour.
“The proposed change to introduce a new slot limit for Murray cod in Victorian waterways is a very complex issue. My opinion on the proposed changes is mixed. I believe there are some real positives for the introduction of the [tighter] slot limit however I also believe there are potential negative ramifications in the current proposal.
My major objection is to the proposed reduction in the minimum size limit because
1 The increase in the number of Murray cod which will be available to be taken by anglers may have a negative impact on the state of the fishery as a reduced amount of fish may make it to a breeding size.
2 The current minimum 60cm limit has been working.
3 A reduction in the minimum size limit runs the risk of disenchanting the anglers who practice catch and release.
4 The current minimum 60cm size limit for Murray cod helps promote and educate recreational anglers to the benefits of catch and release.
5 The current minimum 60cm size limit provides anglers with a good challenge and a higher skill level is required to land a Murray cod which is 60cm or over in size.
6 The reduction in the minimum size limit will see a significant increase in the amount of Murray cod which are being taken by anglers.
I think reducing the minimum size limit for Murray cod runs the risk of the old saying ‘Robbing Peter to pay Paul’.
I do agree with the introduction of an upper size limit for Murray cod. This will help protect those larger Murray cod and provide anglers with greater angling opportunities in the future. Hopefully greater numbers of larger Murray cod will produce increased natural recruitment in the future.
I do agree the current proposal of a 50-70cm slot limit does have some significant benefits. The introduction of the upper limit automatically protects all of those Murray cod above 70cm in Victorian waterways. Murray cod will grow quicker in the proposed slot limit of 50-70cm and therefore are in the slot limit for a smaller time period compared to the 60-80cm slot limit I favour.
The 60-80cm slot limit for Murray cod would be the best option. This would continue to protect the smaller Murray cod and also protect those larger fish. I believe that the upper size limit would then be able to be addressed in the future. This would keep those anglers who would like to take a Murray cod for a feed and those anglers wanting to practice catch and release satisfied, whilst also achieving the end goal of seeing greater numbers of Murray cod in our waterways.
Ross Winstanley has had a long career in fisheries management and is currently a vital source of sensibility in most debates about fishing in Victoria. Ross is my go to man on topics that relate to fish welfare, fish populations and the exploitation of those populations. Oh yeah, he also loves lure casting for native fish with a fervour I remember having 20 years ago!
“Over the past 10 years, Victorian anglers have invested a lot in cod stocking, habitat improvements and in research which has included investigations into anglers' fishing experiences and their attitudes towards the fishery and its management.
The collaboration between researchers at Snobs Creek and ARI has produced some outstanding results - it's great to see that all this work and investment will be applied in the form of modern management arrangements that improve both our fishery and our cod stocks.”