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Thread: SEQ Snapper stocks

  1. #1

    Exclamation SEQ Snapper stocks

    Rebuilding snapper stock a priority for new fishery working group


    Fisheries Queensland·Monday, August 27, 2018







    Queensland’s new Rocky Reef Fishery Working Group will be asked to identify options to rebuild the snapper stock, which continues to be considered overfished.


    Minister for Agricultural Industry Development and Fisheries Mark Furner announced the new working group, which will provide advice to the government on managing fisheries including snapper, pearl perch, teraglin jew, yellowtail kingfish, cobia and mahi mahi.


    Mr Furner said the Queensland Government’s Sustainable Fisheries Expert Panel had considered the latest snapper stock assessment, including an independent review and agreed with the findings.
    “Snapper is an iconic species and it is important that management arrangements ensure Queenslanders can continue to catch and eat a snapper into the future,” Mr Furner said.


    “The new Rocky Reef Fishery Working Group will now review all the information as a priority and recommend options to rebuild snapper stocks through development of a harvest strategy for the fishery.”
    Mr Furner said changes to size and possession limits introduced in 2011 have not been sufficient to improve snapper stocks since the previous stock assessment in 2009.


    “The latest scientific advice is that the biomass of the east coast snapper stock is 10-45% of the original biomass,” Mr Furner said.


    “The Queensland part of the stock, which has been considered overfished for the last six years, is potentially lower at 10-23% of the original biomass and anywhere below 20% is cause for concern.”


    Sustainable Fisheries Expert Panel Chair Associate Professor Ian Tibbetts said despite uncertainty about the exact biomass level, there are clear signs snapper stocks are in poor condition.


    This includes declining catches from both the commercial and recreational sector, fewer older fish in the population and declining numbers of juvenile fish in Moreton Bay recruitment surveys, particularly since 2013.
    “The Sustainable Fisheries Expert Panel was set up to provide independent, evidence-based advice on fisheries management and has recommended urgent and strong action to rebuild snapper stocks,” Associate Professor Tibbetts said.


    “Snapper has been classified as overfished for many years and there are no signs of recovery despite management interventions, marine park closures and bycatch reduction in Moreton Bay.
    “There may be some environmental factors such as water temperature affecting the stock, however, local action still needs to be taken.


    The Rocky Reef Fishery Working Group made up of commercial, recreational and charter fishers and science/conservation representatives, will meet in September to consider the snapper stock assessment and options to rebuild the stock.


    The group will also develop a harvest strategy for pearl perch which is also considered to be a depleting stock.


    As part of the Queensland Government’s Sustainable Fisheries Strategy, clear biomass targets have been set and harvest strategies are to be in place for all fisheries by 2020.


    The Stock assessment of Australian east coast snapper (Chrysophrys auratus) is available online at http://era.daf.qld.gov.au/6341



    For information about the Rocky Reef Fishery Working Group, visit https://www.daf.qld.gov.au/business-priorities/fisheries/sustainable-fisheries-strategy/fishery-working-groups



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  2. #2

    Re: SEQ Snapper stocks

    Here we go again. Of course Fisheries thinks the stock has continued to deplete. More boats got sold in QLD since 2009 and that directly correlates to less snapper in their models.

    All the anecdotal evidence I’m hearing is Snapper this year hasn’t been this good in ages. But I don’t fish the bay any more or the Gold Coast.
    Democracy: Simply a system that allows the 51% to steal from the other 49%.

  3. #3

    Re: SEQ Snapper stocks

    My last 5 trips to Mud island have been before dawn on a week day and in those 5 trips not one Snapper was caught, not even a little throw back, I just don't bother anymore.

  4. #4

    Re: SEQ Snapper stocks

    Quote Originally Posted by alleycat View Post
    My last 5 trips to Mud island have been before dawn on a week day and in those 5 trips not one Snapper was caught, not even a little throw back, I just don't bother anymore.
    come up the sunny coast. Plenty of Snapper around.
    Democracy: Simply a system that allows the 51% to steal from the other 49%.

  5. #5

    Re: SEQ Snapper stocks

    As FQ has eluded to, the rec fishing data and original bio-mass are largely an unknown. The scientists behind the data collection and resultant theories, management plans and suggestions do their best given the limited inputs.

    Anecdotal evidence varies so much it is hard to gauge any reliable status.

    What we do know is overall the rec fishing Snapper industry appears to be quiet. This data relies on surveys, FQ trolling through social media and online forums.

    If they looked at fishing magazines and TV shows, it would appear Snapper are in plague proportions. !

    The Moreton Bay long time fishos( hard core ) are doing just as good today as they were 10 years ago. The 10 % Vs 90% adage.

    Add into the equation the land drought of the last 6 years or so and we can get an idea of what is happening.

    The 3 things that have not changed significantly enough to make an improvement in Bioi-Mass are :-

    1.................Trawlling effort / by-catch

    2...................Artificial Reefs

    3............... subsequent increased fishing pressure due to green zones on other areas

    I won't go over and over the statements of the past in relation to this, nothing has changed........ despite new size and bag limits. IMO of course.

    LP
    Last edited by Lucky_Phill; 28-08-2018 at 01:53 PM.
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  6. #6

    Re: SEQ Snapper stocks

    Phill, going back to the previous RRFF review I got up and questioned the mathematician’s model to their faces.

    Part of that question/statement was that the assumption that there was a direct correlation between recreational boat sales and Snapper biomass reduction from the previously limited stock assessment (shit data in shit data out), meant that not only was their model biased towards always coming up with an answer that showed a reduction in biomass, but that using the same model in the future, regardless of actions taken at the time, meant that biomass estimates in the future would also show a reduction in biomass. They had no response to that. They sat there with blank stares on their faces because they knew they’d be back here with another paid gig within a decade. We were always on a hiding to nothing by allowing them to implement an agenda using flawed models. Here we are again going through the same thing.

    The other thing I criticised was their very quick rubbishing of their own data when one model showed no decline in biomass from solid data from commercial snapper fishermen. They automatically called the result “Hyper-Stable” because it contradicted data from Gold Coast charter operators (data that is highly area specific and prone to other factors that would suggest Hyper-Depletion). Then they did their magical mathematics using new formulas to show the stock was in decline. Using two completely different models they compared apples and oranges and came up with the result they wanted from the start.

    I have no argument that certain areas are over fished. I have no argument that the stock is “Growth Overfished” meaning that such a slow growing fish with over 100 years of fishing pressure is going to have a lot less larger fish in the biomass. That’s just common sense.

    On growth over-fishing, I am pretty sure I made the same point back in 2011. Snapper is a slow growing fish. A 70-74cm fish is on average about 10 years old. The move to allow only 1 fish over 70cm is only 8 years into action. A just legal fish in 2011 only started becoming partially protected 2 years ago. It’s going to take considerable time to assess if these previous measures are bearing any fruit and are actually working. By doing another review so soon, they’re guaranteeing that the result will be that “further measures are required”.

    On area specific over fishing. What does any stakeholder believe the chances are that FQ will look at Moreton Bay or GC data and label it “Hyper-Depleted”???. What does any stake holder believe the chances are that on the back of that, area specific measures for Moreton Bay and the GC area will be implemented??? I think the chances are somewhere between zero and F-All. There is a myriad of reasons to do so! 2.5 million people live in this area alone. That is a lot of potential pressure for what is a tiny area in the context of the fishery that goes as far north as proserpine. That’s 1200km of coast line. The vast majority of people are fishing in 1/6th of that area.

    There has to be a reason why from Caloundra north, there seems to be no complaints about Snapper stocks. IMO and from what I am hearing from a lot of Rec’s I talk to, the Snapper fishing seems to be getting better every year. What I am concerned about is 1200km of coast line receiving completely unnecessary further restrictions on the RRFF fishery because Moreton Bay and GC reefs are a car park in any decent weather. Something that we ALL knew would be made worse with the MBMP implementation.

    Do we need area specific management plans? Absolutely!

    Do we need to dig our heels in this time and demand that credible data collection systems to be put in place for the Rec sector? Absolutely! We were almost unanimous in agreement last time on this but it was put in the too hard basket.

    Do do we need more artificial reefs? Absolutely, but not just in the bay and GC. Give people in this area an incentive to fish north of this over-fished region.

    Do do we need to seriously consider stocking? Absolutely, but I guess that needs to coincide with area specific measures that will ensure increased fecundity. No point spending big bucks adding millions of snapper fingerlings if the vast majority of them will never make it to legal size and add to recruitment.

    Do we need to target other measures that contribute to a healthy nursery? That’s pretty hard to do when even a green Labor government are willing to landfill estuaries and clear hectares of mangroves just so Brisbane airport corporation can add a shopping precinct in their airport upgrade.

    Last time around, even as bad as FQ were in this, even they weren’t listened to. We had a moron minister make a decision that not even FQ were asking for. What’s the point in even participating in a working group when we got shat on last time and will likely get shat on again?
    Democracy: Simply a system that allows the 51% to steal from the other 49%.

  7. #7

    Re: SEQ Snapper stocks

    Review of the snapper stock assessment 2018 - Queensland component
    Barry Pollock
    OVERALL CONCLUSIONS
    The report, “Stock assessment of Australian east coast snapper, Chrysophrys auratus: predictions of stock status and reference points for 2016” (Wortmann et al. 2018), was recently released by the Qld Department of Agriculture and Fisheries. This is a review of that report, providing a scientific appraisal of the Qld component of the snapper stock assessment. This review has found that the Qld catch rate time series (snapper catch and effort over time) are inaccurate, and in some cases dubious, and should not be regarded as reliable indicators of snapper abundance. The single exception to this is the Qld commercial logbook time series. The fishery independent survey in the Moreton Bay region of age group 0+ snapper, outlined in the report, lacks details on methodology and a robust discussion of results. The results showing low levels of snapper recruits per hectare in juvenile habitat suited to beam trawl sampling (?), even in years when recruitment was stable, raises uncertainties about the accuracy and efficiency of the sampling methods. Consequently the relationship between the results of the survey and total recruitment of juvenile snapper in Qld is uncertain. The known biology of snapper (rapid early growth and small size/young age at maturity, high fecundity, disbursed and relatively small spawning aggregations in Qld, ability to live in an extremely wide variety of habitats over huge inshore and offshore areas) and the highly restrictive characteristics of the Qld snapper fishery (lines only with limited hooks, weather dependent, very high minimum size limit, very low possession limits on recreational and charter fishers, variability in snapper fishing skills – especially recreational fishers) leads to the conclusion that recruitment overfishing is extremely unlikely if not impossible. The presence of very large/old snapper (> 70cm total length, 15+ yo) at low levels in the population indicates the possibility of growth overfishing. However if growth overfishing is present, it is not expected to significantly reduce egg production by the total population. (Note the recent rebuttal comments by Hilborn that the value of large females in population egg production is overstated).
    Given the dubious nature of the inputs to the model, especially supposedly declining catch rates over time as an indicator of reductions in snapper abundance, the conclusions that major declines have occurred to snapper biomass in Queensland are questionable and probably incorrect. The resulting management imperative to rebuild the snapper biomass in Queensland is therefore unnecessary. Snapper fishery management has been very restrictive in Queensland particularly since the previous management review in 2008 - 2011. From a biological viewpoint, maintaining the existing Queensland snapper management interventions is adequate and responsible, given incorrect projections about declining biomass. Further restrictions on the Qld snapper fishery which might include an increase in the minimum size, reduction in the possession limit, further restrictions on keeping large snapper, or seasonal fishing closures are regarded as unnecessary, even irresponsible.
    REVIEW DETAILS
    This review provides a scientific assessment of Queensland catch rates that were used as “input data” to the current snapper biomass modelling described in the report. These snapper catch rate time series include data from commercial logbooks and Qld Fish Board landings, historical assessments of charter fishing from old media reports, and the series of Queensland annual State-wide recreational fishing surveys to estimate total catch and total effort by the recreational sector. It also considers the validity of the snapper recruitment surveys in the Moreton Bay region. The relationship between snapper biology and the snapper fishery in Queensland is described and assessed. In conclusion, this review provides a critical assessment of the efficacy of the predictions from modelling that the Qld snapper population is severely overfished.
    The publication “Stock assessment of Australian east coast snapper, Chrysophrys auratus. Predictions of stock status and reference points for 2016” states:
    “The key population status indicators were snapper catch rates and age frequencies.”
    “The current stock assessment using data from New South Wales and Queensland, was run from 1880–2016”,
    “Stock levels for this assessment were estimated to be low (between 10–45 per cent of virgin or unfished spawning biomass)”,
    “Model analyses that used line catch rates (New South Wales and Queensland data) as the index of abundance estimated spawning biomass ratios in 2016 between 10 per cent and 23 per cent.”
    1. Catch rate time series as an index of snapper abundance
    The report on snapper stock assessment released in 2018 states that “The key population status indicators were snapper catch rates and age frequencies.” The fundamental issue in assessing the snapper stock is whether the catch rate time series (catch and effort over time) is proportional to snapper abundance. This point was strongly made in the evaluation by the expert consultant Chris Francis of the Qld snapper model by Campbell et al. (2009).
    The validity of four different time series on Queensland snapper catches as indicators of snapper population abundance is appraised:
    (a) Qld commercial logbook data and Queensland Fish Board landings
    Figure below. Qld commercial CPUE for snapper over time as determined from compulsory logbooks (graph copied from Qld Fisheries DAF 2016 Queensland Stock Status Workshop Report).

    Log books for commercial fishers became mandatory in 1988. The above graph indicates relatively stable catch rates for snapper from 1988 to 2015 – except for increases during the period 2003 to 2008 when an investment warning was issued by the Qld Government. These short-term increases are typical of fisher’s behaviour following investment warnings – increasing reported catches in individual logbooks so as to benefit from possible management interventions. The average catch is approximately 35kg per day which equates to about 25 snapper per day.
    From 1937 to 1975 the commercial catches of snapper were recorded by the Queensland Fish Board. However not all snapper caught by commercial fishers were sold through the Fish Board. For example fishermen’s cooperatives at Mooloolaba and Sandgate operated in competition with the Fish Board in procuring fish from the fishers. Fishing effort was not recorded. Therefore the calculation of catch rates from annual landings at Qld Fish Board depots (Figure below) is not possible.

    (b) Charter boat historic catches – from late 1800s to present (Thurstan et al. 2014)

    Comparisons with contemporary data (from Thurstan et al 2014, Fig 3). “Contemporary catch rate data were sourced fromthe southern offshore Queensland charter boatindustry (data provided by Ray Joyce, Pacific MarinelifeInstitute), which recorded numbers ofsnapper and other fish species landed by charterboats fishing out from the Gold Coast from 1993to 2013 (open circle in Fig 3 above). The advantages of this particular contemporarydata source as a basis for comparisonare that it has a reliable measure of fishing effortin number of hours and number of fishers, andthe historical data also relate primarily to charterfishing.”
    An example of catch exaggeration (from Thurstan et al 2014): “The Brisbane Courier presents the longest unbroken series of catch rates, between 1871 and 1933. On two occasions, reported catch rates exceeded 37 snapper per fisher per hour.”

    Other exaggerations and dubious reports on snapper catches are common in early media reports. Highly skilled recreational snapper fishers and charter operators report that it is physically impossible for a charter group of anglers to catch 37 snapper per fisher per hour. The time series of catch rates for snapper in Fig 3 (from Thurstan et al. 2014) above compares media reports of outstanding/exaggerated snapper catches (1871 to 1939) with records of Ray Joyce who interviewed charter skippers on the Gold Coast (1993 to 2002). The Joyce data covers all charter catches even when snapper were not targeted, and many low catches were recorded for a variety of reasons (groups not wanting to bag out on snapper, poor weather conditions, lack of angler skill, use of inferior bait and fishing gear). A valid comparison would be obtained by comparing “like with like”. In the period 1993 to 2002 the data should be confined to only the most noteworthy snapper catches. Numerous such examples are available on the websites of charter operators who target large catches of snapper. The photo below is one such example of a Gold Coast catch taken on a short charter in 2017 (all participants with bag limits of 4 snapper, all over 35cm).



    (c) Queensland recreational fishing data – State-wide surveys
    From Taylor et al. 2012. “The statewide telephone-diary surveys conducted by Fisheries Queensland from 1996–2005 (McInnes, 2008) used a different survey design to the current survey. The catch data obtained from these surveys provided indicative catch information for each survey year but could not estimate with confidence the detailed catch and effort statistics such as those presented in this report. The results from the 2010 survey are considered to be more accurate as the design of the survey gives far greater consideration to known sources of bias (Harthill et al., 2012). More information on how this survey differs from previous telephone-diary surveys is provided in the Diary survey section of this report.”
    The problem with the Qld State-wide surveys 1996–2005 is that the catch diaries were subject to “recall bias”, the tendency for recreational fishers to exaggerate their catches (both in terms of numbers and fish-size). The latter surveys by Taylor et al (2012) and Webley et al. (2015) undertook validation procedures to eliminate recall bias, and hence reduce the estimates of total snapper catch. The results for the time series of recreational catches in Qld is that the early surveys, 1996 to 2005, over-estimate total catch in comparison to the later surveys, 2010 to 2015.
    Table below. Summarises estimates of Qld total snapper catches by recreational fishers from State-wide surveys
    Year, survey reference, total snapper kept in Qld, total weight of kept-snapper in tonnes.
    1997 RFISH (Higgs 1998) 577000 519
    1999 RFISH (Higgs 2001) 527116 474
    2000 RFISH (Henry and Lyle 2003) 252229 227
    2002 RFISH (Higgs et al. 2007) 296440 267
    2005 RFISH (McInnes 2008) 327783 552
    2010 SWRFS (Taylor et al. 2012) 83898 135
    2013 SWRFS (Webley et al. 2015) 55625 82

    Qld recreational fishing effort - overall participation levels decreasing. (From Webley et al 2015)

    The accurate Qld State-wide survey data from 2010 and 2013 show that the total snapper kept-catch has decreased from 84,000 to 56,000. However the total recreational fishing effort has also decreased. In addition the bag limit for snapper was 5 in 2010 and 4 in 2013 – also contributing to decreases in snapper catches. Considering these factors, snapper catch rates by Qld recreational fishers from 2010 to 2013 are much more stable than those used in the current modelling.
    CONCLUSION 1. Catch rate time series as an index of snapper abundance.
    The report on snapper stock assessment released in 2018 states that “The key population status indicators were snapper catch rates and age frequencies.” The fundamental issue in assessing the snapper stock is whether the catch rate time series (catch and effort over time) is proportional to snapper abundance. This point was strongly made in the evaluation by the expert consultant Chris Francis of the Qld snapper model by Campbell et al.2009.
    In the current review four different Queensland time series are considered. The commercial logbook snapper series, 1988 to 2015, appears to be the most accurate. It shows stability of catch rates other than for a brief period corresponding to the Government’s investment warning, 2003 to 2008. It is possible that hyperstability may be involved where commercial fishers move to more productive areas, however the presence and impact of hyperstability needs careful examination. Fishing power may also have increased, but this is unlikely to be highly significant during the period 1988 to 2015. The Queensland Fish Board records of commercial landings from 1937 to 1975 are an unknown part of the total commercial snapper catch. No matching effort data are available for Fish Board landings data. Therefore the calculation of accurate catch rates from annual landings at Fish Board depots in Queensland is not possible.
    Comparisons of old media articles with contemporary information on snapper catches by charter fishing (eg. Thurstan et al 2014) are dubious. The media articles, 1871 to 1939 contain details of outstanding catches, often with exaggerations. Contemporary data collected by Ray Joyce from Gold Coast charter operators, 1993 to 2002, is not directly comparable with old media articles. During recent times outstanding catches are often made by charter groups of recreational fishers on the Gold Coast, equivalent to those made in the late 1800’s and the early 1900’s. Comparisons of snapper catches over time should have matched the outstanding media reports (discounting for exaggerations) with outstanding contemporary snapper catches by charter operators – not with the Ray Joyce data.
    The Queensland State-wide recreational fishing surveys used different methodology from 1997 to 2005 compared with more recent surveys, 2010 to 2015. The early surveys overestimated total snapper catch due to recall bias in the catch diaries. In addition total fishing effort has decreased substantially from 1997 to 2013. Changes to size limits and possession limits on snapper have also occurred during the period of these State-wide surveys. For these reasons the time series of catch and effort for snapper in the recreational fishery, based on the State-wide surveys are not accurate indicators of changes in snapper abundance.
    2. The snapper recruitment survey in Moreton Bay, a fishery independent survey
    Figure 3.11 below. Standardised catch rates from the Moreton Bay sampling program of young snapper (From snapper stock assessment report 2018 by Wortmann et al.)


    CONCLUSION 2. The snapper recruitment survey in Moreton Bay.
    The accuracy of the snapper recruitment survey results in the Moreton Bay region is uncertain – given the absence of information provided on survey methodology, and lack of a robust discussion of the findings. It is surprising that such low levels of abundance (eg. 10 to 15 snapper of the 0+ age group per hectare) occur in prime juvenile habitat areas from 2007 to 2013 - prior to “recruitment reductions”. This result alone raises questions about the accuracy and efficiency of the sampling methodology. The notion that Fig 3.11 demonstrates snapper recruitment failure for the entire Qld snapper stock due to overfishing is questionable to say the least.

    3. Snapper biology and fishery relationships
    In Queensland, snapper reach sexual maturity at 26cm total length and approximately 1.7 years of age (Stewart et al. 2010). They are serial spawners over a protracted period each year. They do not form dense spawning aggregations in Qld like mullet or tailor, but have smaller spawning aggregations at a variety of water depths and locations. Fecundity is very high, but egg production within the entire adult population by the very large female size-classes is expected to be low in comparison to the small and mid-size females. (Several mainly theoretical/modelling papers have been published in recent years advocating protection of large highly fecund female teleosts. Other modellers have disagreed. For example the rebuttal by the much respected Ray Hilborn: "Ray Hilborn, a fisheries biologist at the University of Washington in Seattle (does not agree). He argues that because superspawners are relatively rare, even in unfished populations, their overall contribution to the population is not particularly great. Accounting for superspawners would make “little difference to how you manage a fishery,” he says).
    Snapper have a short planktonic larval stage in open waters. Juveniles occur in inlets, embayments and other sheltered marine waters, often over sand, mud, seagrass and rocky habitats. The adult fish are remarkable in relation the extent, diversity and large area of habitats and depths they are able to colonise. For example adult snapper can inhabit estuaries (eg. Brisbane River and Pumicestone Passage), embayments (eg. Moreton Bay and Hervey Bay), intertidal areas (eg. Peel Island and Mud Island) and offshore to depths of 60m or more. In these offshore habitats they occur in both the water column and close to the substrate.
    These biological characteristics of snapper and the existing constraints on the snapper fishery in Queensland, particularly limitation to only line fishing with limited numbers of hooks makes snapper unlikely to be depleted by fishing in Qld. Other characteristics which reduce their vulnerability to fishing are their dawn/dusk feeding patterns, and most of the adult habitat is subject to weather which makes fishing difficult/impossible for much of the year. Recent minimum size limits (35cm since 2002) enables mature snapper to spawn for one or two years before entering the fishery.
    The snapper fishery is dominated by fish in the range up to 40 cm total length. However fish in the range 30cm to 35cm are extremely common in catches (Fig 10.15). At present the entire recreational catch of snapper in Queensland is made up of 75% discards due to being undersize, and 25% kept catch. Snapper is a long-lived species, but very few individual fish over 70cm total length are taken in the Qld fishery. (Ferrell and Sumpton 1993. Fig 10.15 below for example shows the size-frequency of snapper taken by recreational (charter) fishers). However the extreme size/age distribution of snapper makes them vulnerable to growth overfishing – that is reduction in the larger size-classes (eg. greater than 70cm total length).


    CONCLUSION 3. Snapper biology and fishery relationships.
    The reproductive characteristics of snapper (size at maturity 26cm total length, and age 2yo), rapid early growth rate, high fecundity, relatively small and dispersed spawning aggregations over wide areas in Qld, extreme diversity of habitat from intertidal zones to deep (60m) offshore waters, and the snapper management arrangements (eg hook only fishery, min size 35cm, 4 possession limit) makes recruitment overfishing unlikely in Qld. Their long-lived characteristic (eg. > 70cm and 15+ years old) could result in growth overfishing. However if growth overfishing is present in snapper in Qld, it is not expected to significantly reduce egg production by the total population. As a result of the low levels of large snapper in the Qld population, their overall contribution to egg production is not particularly great.

    4. Predictions from the 2018 snapper stock assessment modelling and future management
    The 2018 snapper stock assessment report states in summary:
    “There was an accelerating nature of decline in estimated spawning biomass relative to estimated virgin spawning biomass from 1950 to 1990. This decline was consistent with the harvest increases during that time period. After 1990, estimated spawning biomass ratios levelled off. For model analyses that used trap catch rates (New South Wales data) as the index of abundance, estimated spawning biomass ratios in 2016 were between 20 per cent and 45 per cent. Model analyses that used line catch rates (New South Wales and Queensland data) as the index of abundance estimated spawning biomass ratios in 2016 between 10 per cent and 23 per cent. The different signals in the New South Wales commercial trap catch rates and the line catch rates complicated the status of the stock as a whole, but suggests that localised depletion in Queensland is likely to have occurred.
    Despite the differences/range of biomass estimates, the assessment recommends a reduction in overall fishing mortality to rebuild the stocks of this long-lived and iconic species to more sustainable levels. Effort will need to be reduced for any rebuilding of population sizes to occur. The rate of recovery will depend on the extent of the restrictions on harvest.”
    The inconsistency in estimated spawning biomass levels between NSW trap fishery data (20% to 45%) and Qld/NSW line fishery data (10% to 23%) highlights the dubious nature of the model projections using inaccurate data. The explanation above – that line fishing in Qld has caused localised depletion is highly speculative and dubious – given the heavy fishing pressure of the NSW trap fishery which has much less comparative impact on the snapper stock, according to model projections.
    CONCLUSION 4. Predictions from the 2018 snapper stock assessment modelling and future management
    Given the dubious nature of the inputs to the model, especially information on reductions in catch rates over time as an indicator of declining snapper abundance, the conclusion that major declines have occurred to snapper biomass in Queensland are incorrect. The resulting management imperative to rebuild the snapper biomass in Queensland is therefore questionable.
    Snapper fishery management has been very restrictive in Queensland particularly since the previous management review in 2008/2011. From a biological viewpoint, maintaining the current Queensland management interventions is reasonable and responsible, given the uncertain status of the current (2018) assessment findings on stock status. Further restrictions on the Qld snapper fishery which might include increase in the minimum size, reduction in the possession limit, further restrictions on keeping large snapper, or seasonal fishing closures are regarded as unnecessary, even irresponsible.

    September 2018
    Literature cited
    Campbell, A. B., M. F. O'Neill, W. Sumpton, J. Kirkwood, and S. Wesche. (2009). 'Stock assessment of the Queensland snapper fishery (Australia) and management strategies for improving sustainability'. Queensland Primary Industries and Fisheries Report.

    Ferrell, D. and Sumpton, W. (1993). “Assessment of the fishery for snapper (Pagrus auratus) in
    Queensland and NSW”. FRDC Report 93/077

    Henry, G. W., and J. M. Lyle. (2003). “The National Recreational and Indigenous Fishing Survey”. Final Report No. 48, National Heritage Trust, Canberra.

    McInnes, K. (2008). “Experimental results from the fourth Queensland recreational fishing diary program (2005)”. Queensland Department of Primary Industries and Fisheries.

    Stewart, J. (2015). Snapper (Chrysophrys auratus) in “Status of fisheries resources in NSW 2013-2014”. NSW Department of Primary Industries.

    Taylor, S., J. Webley, and K. McInnes. (2012). “2010 Statewide Recreational Fishing Survey”,
    Queensland Department of Agriculture, Fisheries and Forestry.

    Thurstan, R., Campbell A., and Pandolfi, J. (2014). “ Nineteenth century narratives reveal historic catch rates for Australian snapper (Pagrus auratus)”. Fish and Fisheries 17: 210-225.

    Webley J., McInnes, K., Teixeira, D., Lawson, A and Quinn, R. (2015). “ State-wide Recreational Fishing Survey 2013-2014.” Queensland Department of Agriculture and Fisheries.

    Wortmann, J., O’Neill, M., Sumpton, W., Campbell, M. and Stewart, J. (2018). “Stock assessment of Australian east coast snapper, Chrysophrys auratus. Predictions of stock status and reference points for 2016”. Qld Dept of Agriculture and Fisheries, New South Wales, Department of Primary Industries.
    Author profile. Barry Pollock (PhD, U of Q) has been the Scientific Editor of a Queensland scientific journal, Proceedings of the Royal Society of Queensland, for the past four years. He is often invited to peer-review for other scientific journals on fish biology. Prior to retirement he held positions of Director, Fisheries Branch QDPI, General Manager, Fisheries Resource Management QDPI, Deputy Director, Pacific Islands Forum Fisheries Agency. He completed many fisheries related consultancies for the UNDP and FAO, United Nations. Several recreational fishing bodies in Queensland have requested his scientific advice. He has served on several fisheries management advisory committees (eg, Burn’s Inquiry into recreational fishing in Queensland ca.1993, Qld East Coast Finfish Management Advisory Committee ca. 2005, Qld Rocky Reef Stakeholder Network ca. 2008). Barry was raised at Redcliffe, Queensland and has a long family history of recreational fishing in Moreton Bay, including 65 years of family snapper fishing. He has a strong scientific publication record on the fish stocks and fisheries of SE Queensland.

    Reproduced here by permission from Dr Barry Pollock.

    cheers LP
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  8. #8

    Re: SEQ Snapper stocks

    Well said Barry Pollock! That is something we can get behind as it makes so much sense.

    its obvious that those doing these assessments are doing so with a pre-conceived bias towards there being a depleted fishery. How could such methodology be used, and conclusions drawn with such poor data and assumptions, and we not come to that belief.

    I personally wouldn’t mind a change in MLS to 40cm if they give us back the 5 bag and over 70 restriction. I think it would be a better outcome for the fishery, and considering the slow growth of the fish after maturity, increasing the population of 35cm+ fish can’t hurt can it?
    Democracy: Simply a system that allows the 51% to steal from the other 49%.

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