 For those who don't know me, my name is Gavin Begg, I'm the Executive Director here for Fisheries and Agriculture at PERSA. Mike Stier on my left is the Research Director of Aquatic and Livestock Sciences here at SARTI and we'll be presenting the SNAP assessment. If you could hold questions to the end so Mike can just run through the presentation. I know this is eagerly awaited and it's a really important piece of work that SARTI has now completed. This is the first opportunity we've got to effectively brief you guys as key stakeholders and then we'll be rolling out to broader public sessions over the next two weeks. So with that we'll get straight into it. As I said if you could just hold questions to the end and then we'll have time to go through each of those. So over to Mike. Good morning everyone, thanks for coming everyone to my right. So this is a combination of the stock assessment report that was taken about a year in the making and today I'll just go through the key research findings. As we're familiar with SNAPR it's an iconic South Australian species. It's a community-shared species of importance both the commercial wreck, charter, Aboriginal traditional and the consumers. So a very proudly community-shared resource. It typically forms large aggregations to spawn. These aggregations and schools provide quite a good target for fishers. You know we quite often see high catch rates around targeted schools which you know presents alternative problems. It's a long-lived species. You can live up to about 30 years of age. If you look back in the 90s and 2000s and you see a little kid holding a snapper chances are the snappers older than the kid. So very very long-lived. They're slow growing. They take around about four to six years to enter the fishery so nothing happens with this species very quickly. They have variable recruitment means that the juveniles that are resulted from successful spawning contribute to replenishing the populations and with SNAPR we find that that recruitment is very episodic and infrequent. And finally we've seen over the years with our South Australian stocks evidence of stock declines particularly in the gobs. So just a bit of fisheries 101 just to get you back. This is a typical population dynamics figure where we've got the fishable biomass growing through time. As you can see the fish increase in size and diminish in numbers due to natural mortality and also fishing mortality and then we've got the successful recruitment that drives or replenishes the stocks through time. What we find the biomass can grow and respond on the basis of natural mortality in recruitment events. Fishing mortality is the only thing that we can really control through fisheries management. A lot of the other processes that are underpinning the increases in stock biomass are environmentally driven particularly around recruitment. So we go straight to the key findings for the report right up front. The assessment outcomes have indicated that there's been evidence of poor recruitment for more than a decade in both golf. So in fact more than two decades in Spencer Golf and around a decade in Goulson Vincent. We've seen that the closure that's been put in place since November 2019 appears to have arrested the decline in biomass. Through our egg surveys we've seen evidence of higher levels of schooling of fish starting to see that natural aggregation of those fish, those undisturbed schools coming together during the summer months to spawn which may be beneficial to increase that sporting potential into the future. But at this stage we're not seeing any evidence of stock recovery at this stage and I'll walk you through the science to support all those assumptions, all those findings. A lot of information comes into the stock assessment. There's multiple, multiple lines of evidence and this figure here just demonstrates what we feed into the snapper assessment. We've got heavy reliance on fisheries dependent data, fisheries statistics. We've got a considerable amount of statistics that goes back to around 1984. We also pull in very important biological information. So understanding the length and age structures of the snapper populations, both regional populations and stock populations throughout the state. And we also input a fishery independent estimate of biomass or abundance and historically we've used catch rates as a way of coming up with an estimate of abundance. However if you don't have a fishery operating we don't have any catch rates to record. In a closed fishery for example so we'll need alternative methods and we've used the the daily egg production method to come up with an estimate, a fishery independent estimate of spawning biomass and I'll step you through each one of those. All of those sources information then get pulled into a snappest model, a sophisticated model that then pumps out four metrics that we're interested in. Fishable biomass, which is the big one, that just tells us how many fish are in the water of legal size, patterns of recruitment through time. So effectively the engine room of recruitment that's there to replenish stocks into the future and what has occurred in the past. What the general harvest fraction is, so that's the proportion that is taken from that fishable biomass and what the egg production from that fishable biomass is. We pull all that information together through a weight of evidence approach and then we come up with a stock status for each of the stocks. So these are the stocks that we're interested in. We've got three that occur within South Australia. We've got the Spencer Gulf West Coast stock, the Gulfson Vincent stock and then we share the western Victorian stock with Victoria. So that represents the southeast region and we do an assessment on each of those three or those two stocks in that southeast region. So here's the commercial fishery statistics that very much underpin a lot of the input into the stock assessment and you can see for Spencer Gulf West Coast. In this example on the top we have trends in total catch. The green line represents the third highest, the red line represents the third lowest value. On the left here we've got trends in handline catch, targeted catch, targeted effort and catch rates and on these three panels on the right on this on this side here are representative on the long line catch. So we've got two different fishing gears that we that we analyse or consider in the assessment. So historically we've had you know back in the 80s and 90s a fishery around about 300 tonne, 300, 400 tonne it increased in the early 2000s and then again in around 2007 and then we've seen that subsequent decline down to very low levels that have been enduring for a number of years. You can see that the trends in handline catch and long line catch in terms of their targeted catch have declined in corresponding to that overall decline as well as a sequential reduction in targeted handline effort and targeted long lines remained relatively stable over the past well when towards the end of the open season. The other thing we're interested in too is the catch rates. Now remember I said these species aggregate which means that catch rates provide us well with information that we need to be cautiously aware of because in a school your catch rates can remain really high until you catch that last fish and then you'll see a real a real crash of those catch rates and we've seen evidence of precipitous declines in catch rates in the handline sector and in the long line sector historically. Similar for Gulfson Vincent same same information total catch on the top handline catch on the left long line on the right. We can see that historically Gulfson Vincent was a relatively low level fishery around you know less than 100 tonnes through time and then we've had this really ephemeral sort of increase population around that 2009 period 2010. Handline catches were relatively low that targeted catches and you can see the response in the in the long line targeted catch around that time so the very much transitioned from a handline to a long line fishery in Gulfson Vincent. You can see targeted effort for the long line catch went up in well corresponding to these increases in abundance as well as you know really high levels of catch rates in CPUE over that 2010 to about that 2016 or so period where we started to see declines in those long line catch rates. So a very ephemeral burst of of of the population in Gulfson Vincent and then you can see that it has slowly declined in those subsequent years. Southeast region this is the the stock that we share with West and Victoria. The most of the recruitment is driven through successful reproduction and spawning in Port Phillip Bay. As those animals those juveniles grow they spill out and then towards the west into our southeast region. You can see there historically the southeast region had very negligible snap of catch and it wasn't until around about 2008 where we saw a pulse come through which has effectively supported both the handline and the long line sectors and you can see catch rates in the long line sectors remaining relatively high and we've seen another little little blip little increase in around 2020. So that just identifies the historic information that we get that's dependent on the fishery. Questions always get asked also you know how do we account for the recreational catch this is a community shared stock. It's a really important species for the recreational fishery and we do integrate as much recreational all the recreational data that we have into the stock assessment model. So we base the information on the phone and diary surveys that were undertaken in 2000, 2001, 07, 08, 13 and 14 and we do have a just a plug we do have a recreational fishing survey coming out shortly so we'll keep an eye on that. In the intervening years you know we have to estimate recreational catch and we do that on a proportional basis so we understand the proportions that we've got through the recreational fishing surveys and we just apply that to the model. And then in recent years particularly in the southeast we've got the mandatory catch reporting since 2020 that's really shaped or provided a more robust estimate of recreational catch for that region. So all those data get incorporated into the assessment along with the commercial catch the charter boat catch is incorporated as well. Okay now another so we've got the fishery dependent statistics another really important component that goes into the model is our understanding of the population demographics so getting an understanding of the size and age structure of snapper populations throughout the state. So the aging information is really important so we have a routine program where we go and access commercial fish or in a during the close period we we've charted commercial fishes to to get us the samples that we need. We can then get size, age, sex, reproductive condition information from those from those animals. We take the otoliths out we we grind down the otoliths and we can determine the age it's really important to get the age because it gives us a rate based estimate for everything that we do in the assessment. Now for just an example in the report there'll be age structures for each each of the regions so just as an example here these data are from northern spencer gulf you can see that from 2010 through to 2021 there's the age composition but what I want to draw your attention to is that historically around 2010 through to about 2014 we had old fish in the population so this red line just delineates the 10-year-old fish so everything to the right of this red line indicates fish that are older than in 10 years so you can see that we've had you know a relatively good showing of old fish particularly those that were you know in that recruitment year of 97 and 99 that persisted in the fishery for a number of years but if you look at the most recent data over you know from 2021 back you've not seen those 10-year-old fish in the same sort of numbers in fact we're starting to see a truncation in the size of that composition is the fish that generally around about five to seven years or age that are contributing to that population. Now if we go back to 1990 we're seeing fish that were 20 years old 30-year-old fish so we've seen quite an erosion of those those older fish within within both Gulfson Vincent and Spencer Gulf West Coast stocks so it highlights the very important information that we have from a biological perspective to go into the model. The next bit is the fishery independent assessment of abundance like I said historically we used trends in catch rates derived from the commercial fishing statistics we don't have that in a closed fishery so we need an alternative method the daily egg production method has been developed for snapper since around about 2013 or 2014 where we had an FRDC project to refine it over the years we've got better at refining the information that goes into that. This is effectively determines what the proportion of well how many how many fish are required to spawn the amount of eggs that we're finding in our in our samples. The thing that we have to rely on with this particular method is making sure that we validate that the eggs that we're seeing are actually snapper eggs because they spawn during summer time where a lot of other species are spawning you have mixed plankton a whole heap of different eggs from a whole range of different species many of them look very similar snapper in particular have a fairly generic egg so it's really important for us to delineate or identify those snapper eggs from all the others and we've got a a rigorous process in place where we go through the plankton we identify eggs of a particular size that are considered possible snapper eggs we then refine that on the basis of our understanding of the morphology of those eggs and we've had samples grown on eggs grown on sites so we can get a really good understanding of what the morphology is and then we go through and we apply a molecular probe that links the DNA with a substance that turns the eggs blue so we can then identify snapper eggs from everything else we've got quite a really good stepwise approach to identifying those eggs this is important information I don't want you to get confused about this uh this the maths here there's there's two points that I want to highlight here this is the calculation that we use this morning biomass on the top line the PO and the A that represents the information that we get from the egg survey so where we go out and and identify patterns of egg abundance and then on the bottom everything in the purple that's the important bit that we get from the adult sampling you know the spawning fraction the sex ratio the weights the batch fecundity etc all that information then comes in together give us an estimate of spawning by MS4 Spencer Golf and Golf Sun Vincent so if we look at the patterns of egg production since 2013 when we when we developed the methodology and you can see changes in in the the the sampling as we evolved through time but if you look you can see the distribution of eggs the red represents the hot spots of egg of egg abundance so in 2013 we had a relative hot spot in the middle of the northern spencer golf the pattern in 2018 was was quite well distributed in 19 it was a little bit more peppery and then we've seen a real contraction in 2021 and this is that that the return to the aggregation behavior or that schooling behavior that we are hypothesizing is because the the schools have left largely undisturbed the area the spawning area is a really key fundamental part of the assessment of the of spawning biomass and it does have quite a level of weight into the estimate of the spawning biomass and you can see here through time that we've had a reduction in that that measured spawning area and if we compare 2021 to 2019 it's been almost a halving of that spawning area interestingly the number of eggs that were that were collected both in 2019 and 2020 were virtually identical but they were just more contracted into of particular areas. Golfs and Vincent similar story we saw that incredible hot patch in 2014 just off of your peninsula there and if you can compare the the last two you can see a real contraction in spawning activity from 2019 to 2021 and once again we've seen that really large 58% decline in spawning area and there's been a reduction in the number of eggs that we've detected in that survey. So just to reiterate we're seeing this contraction of spawning activity and the hypothesis is because those basic that those stocks have been left largely undisturbed. We're pretty confident in in the fact that we've collected or really got a good understanding of the the spawning activity and this is a great figure to identify that. As we were going out collecting the eggs doing the egg surveys we also contracted commercial fishes because they're the best at catching the fish we're the best at collecting the eggs and they went around and simultaneously targeted the adults. Those spots that are red indicates those snapper that are in spawning condition so they are actively contributing to the spawning population with spawning fractions approaching 100% and those that are in white fish that were collected that were not in spawning condition and you can see we've got quite a good overlap of those red dots those highly active spawning adults and the distribution of eggs as part of that that survey. Right so now we've got the fishery dependent information the historic catch. We've got the biological information from our age length sex and spawning information. We've got an estimate of fishery independent spawning biomass or estimate of abundance. Now we pull all that information together into our SNAPEST model and these are the overwhelming results. So Spencer Gulf and West Coast here on the top we have trends in the fishable biomass through time and then in the bottom we have patterns of recruitment. So you can see historically we had a fishable biomass around 4,000 tons back in the mid 80s dipped down a little bit and then dropped up to around about 5,000 tons that are about 2006 and then precipitously declined through to the closure and you can see in 2022 that we've arrested that decline it's sort of flatlining some might say you might have a little bit of an inflection upwards but there's no variation there's no difference in those standard errors. You can also see on the bottom the recruitment events from 1980. So what's that 40 plus years of data and we can see three very clear recruitment of events. Now if we join them up so we see a huge recruitment event in 1991 that really helped build the biomass in Spencer Gulf and then we had subsequent notable recruitment events in 1997 and 1999 that also contributed to bumping up that biomass. What you do see here is that recruitment does contribute to increases in biomass but you don't necessarily see good recruitment when biomass is high because it's not a strong stock recruitment relationship. What we have also seen that over the past 20 years or more in Spencer Gulf West Coast that we've seen no marketed recruitment events and a subsequent decline in biomass and that would have been through fishing activity, natural mortality. So you clearly can see a relationship around how recruitment is required to replenish those stocks. Some Vincent it's a different pattern but similar philosophy where you've got you know fishable biomass historically was around about a thousand tons. We've seen that increase quickly into that 2008 period reflected of those catches that we saw earlier and you can see how recruitment events which have been more frequent than Spencer Gulf have helped contribute to increasing that biomass and then a period of 10 years of low recruitment although we did see a bit of a blip in 2014 but didn't appear to manifest markedly into that fishable biomass. So once again those declining and reduced biomass through fishing and we've seen in 2022 the latest one where we've arrested that decline and that clearly would have been as a result of the closure. So I guess if you think about it like a bank account you know you have a savings account that you deposit money in through time and that's your recruitment and you withdraw money. It appears in both Gulfson Vincent and Spencer Gulf that we've been withdrawing from that account much more than we've been depositing. So if we pull that into a graphic this is the one we saw earlier so historic sustainable fishery would look like this you know we've got a healthy biomass that's growing you've got reproduction that's driving the the replenishment of those stocks you've got natural mortality occurring and you've got fishing mortality occurring under under some level of management and then if we look at what the situation we have now it appears that we've got a depleted fishable biomass not a lot of spawning potential because the the biomass has been eroded. With that we've got probably not the propensity for having strong recruitment events because you don't have that spawning biomass to generate their positive recruitment and we also don't have an understanding of what the environmental conditions are required to embolden that that that that positive recruitment. So it appears that we've now got a situation in both Spencer Gulf of West Coast and GSV where we have these depleted stocks. Southeast region different story we are on the top here you can see that we've had that increase in the fishable biomass you can largely see that that's been driven by very strong periods of recruitment from Port Phillip Bay and their surveys that occurred in Port Phillip Bay that be able to let us know or give us some sort of indication of those the strength of the incoming recruitment and relatively low exploitation. So this this southeast region is is stabilised and considered relatively stable. The fact that we've got huge standard areas here is just reflective of the we've had to change how we've incorporated the estimates of abundance through standardising our catch rates. We've gone from a handline fishery to a long line fishery and those there's no comparability in that change over so what we've done is standardised our understanding of catch rates by looking at the number of hooks rather than the fishing gear. So the overall outcome both Spencer Gulf West Coast and the Gulf's and Vincent stocks remain classified as depleted on the basis of low biomass and extended periods of poor recruitment. The expected time frames for recovery are unknown well given what we know about the slow growth of snapper and the fact that we've got episodic recruitment it's it'd be very difficult to put in a time but we can say that recovery may take several years or possibly longer on the basis of our understanding of their slow life history and in the end there's been no changes to the stock status. Spencer Gulf and West Coast still considered depleted Gulf's and Vincent stocks still depleted and the southeast region that we share with the Western Victoria stock remains sustainable. So that's the overarching results from the stock assessment. The stock assessment is comprehensive and will be released shortly and much much greater level of detail in that assessment for your perusal. Just need to say there's a lot of work that has gone into this and a pretty massive team. The SARDI team has has been singularly focused and delivering the stock assessment. We've had really good collaboration with the Moran Scarfish Fishes to collect the important adult sampling and also the the charter boat sector and then the fish processes that also helped us ensure that none of those fish that were sampled went to waste and were donated to the food bank. That's it from me. Very happy to open it up to any questions. Yep, do you have biomass estimates? Well they're here. So the biomass estimate for Gulf's and Vincent is what is that around 400 tonne and then Spencer Gulf, there are more than that less than a thousand tonne but that they will be in the report. Sorry I didn't see if there's anyone online. There's no one online so it's just us. Okay, I've got a spawning area because obviously you know giving that as a key driver in terms of surveys but I assume in certain terms if you have a contraction of spawning area to see recovery you expect to see a huge amount of beings in that contracted area through that period of time. So it's probably for me about the alignment of the surveys with spawning time. Yep, yeah and look that's Sophie go to this figure here or this so what happens the alignment so say for example spawning fraction is low so we're not seeing what we can adjust for the relative proportion of spawning activity by getting an estimate of spawning fraction. So if we're out there and the spawning fraction is 10% then we adjust for that in the estimate of spawning biomass. So it is captured in the fundamentals for the daily production. Oh Danny. There'll be zero because it's closed. Oh no that didn't put that in there but it's in the report. And this spawning area, the validation that you go against changing environmental conditions. Well we've got some it's a real struggle actually to understand what's driving recruitment. We are two years into a three-year FRDC project that's trying to understand what the dynamics are that are shaping recruitment processes in our Gulf. What we do know from Port Phillip Bay, there's been quite a lot of work done around patterns of recruitment there, that it's really about the timing of the eggs that hatch and that grow to a larvae with the flushing of the Yarra River, the nutrient mix of the fighter plankton so they're effectively matching with the hatching with times of high food availability. So they've seen that that's been like the you know the Goldilocks sort of approach where conditions are just right. The difference that we have in the Gulf compared to Port Phillip Bay is we don't have that input of fresh water hyper saline or very very very very hyper saline northern part of the Gulf. So this project is looking at trying to disentangle some of those drivers that shape the recruitment. Because you see the contraction that it's actually in some different areas of the Gulf? Yeah yeah and look I think here you know we're seeing fish up in the northern part of the Gulf, right up in Northern Spencer Gulf. Point up up here. So we're catching we're catching fish they're just not spawning they're just not spawning up there. So the short answer is that you know that there is likely environmental drivers but we don't know what what they are yet. It doesn't seem to be an unexpected result given our understanding of the life history of Snapper and given our understanding of the history of the fishery and in particular those episodic recruitment events. We've got any historic data? 319.84 it's sort of yes yep so we go right back to the 70s in Spencer Gulf from 1970 something we've had like five good recruitment events. Is there any evidence previously of this global depletion regarding data around that? Well the evidence from this level of depletion it's only more contemporary from 2006 or so. Yeah but we do and in fact you know there's quite a lot of historic information that I think we're aiming to. We've had a a stalled scientist that's been just just retired from Saudi who's got quite a considerable amount of snapper expertise and through his retirement he's pulling all of that information together so we'll have it. Okay well that's it. Well thanks for your attention and I appreciate you coming this morning. Like Gavin said we'll be on a road show providing this this presentation the same one and happy for you guys to reach out with any questions. Once you've had a a pour through the stock assessment it's a big one but feel free feel free to ask ask questions for scientific clarification if needed. Thanks everyone.