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In early 2011, PIRSA commenced a review of Snapper management arrangements in response to concerns about the future sustainability of the fishery as a result of increasing commercial fishing effort, and a concentration of targeted fishing activity on breeding aggregations by all fishing sectors – commercial, recreational and charter.

 

A number of changes have been implemented through the review process to control the level of commercial impact on Snapper stocks and provide great protection to Snapper spawning aggregations.s included below from the PIRSA website and also info regarding the special closures which continue on from the 15th of December.Just a reminder that the SA snapper fishing closure starts today!

 

A little info is included below from the PIRSA website and also info regarding the special closures which continue on from the 15th of December.

 

 

In early 2011, PIRSA commenced a review of Snapper management arrangements in response to concerns about the future sustainability of the fishery as a result of increasing commercial fishing effort, and a concentration of targeted fishing activity on breeding aggregations by all fishing sectors – commercial, recreational and charter.

 

A number of changes have been implemented through the review process to control the level of commercial impact on Snapper stocks and provide great protection to Snapper spawning aggregations. These include:

  • A 15-day extension to seasonal Snapper fishing closure, which commenced for the commercial sector in 2012 and will apply to charter and recreational fishers from 2013. The annual state wide closure now applies from midday 1 November to midday 15 December annually.
  • A commercial daily commercial catch limit of 500 kg was introduced across all South Australian waters, to control the level of commercial impact on Snapper stocks.
  • Commercial fishers were also restricted to using 200 hooks on set lines (longlines) – reduced from 400 hooks – when operating in Spencer Gulf and Gulf St Vincent to assist in constraining Snapper catches to the 500 kg daily limit and minimising discarding of excess Snapper.
In 2013, Snapper spawning spatial closures were introduced for the 2013/13 summer. The closures encompass five key breeding areas – four sites in Spencer Gulf and one site in Gulf St Vincent – the spatial closures will applied from midday 15 December 2013 to midday 31 January 2014. During this time all fishing sectors were prohibited from possessing, fishing for and taking Snapper within the four kilometre radius of each spatial closure area. These spatial closures are currently being reviewed for 2014/15 summer.

 

More information about the Snapper spatial closure

 

Click here to view the article

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About 20% (including charter sector which makes up just under half of that take) - but this is somewhat dated info based on the 07/08 Rec fishing survey.

This will no doubt be reset by another survey which I believe is currently underway(?)

 

And keep in mind that commercial catch is significantly down over the last couple of years, following the 2010 extraction peak - in fact 2012 was actually slightly less than 2008.

 

Also depends which region one is talking about - the state rec average was assessed as 20% but GSV was nudging 40%.

Then again, currently the Northern GSV area is where the pros get most of their total state catch...

 

How long is a piece of string?

;)

Toss a coin for now, rec catch could be anywhere between 1/6 and 1/3 of total extraction currently...

 

Commercial extraction figures from the 2013 stock assessment report, FWIW;

 

Commercial catch.JPG

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Wholly cow look at the increase in northern st Vincent gulf.

 

I know this has been said ad nauseum by many in the past but I think punishment should be targeted at the perpetrators or causes of the problem which is clearly the commercial sector.

 

In a state that's very light-on for quality decent size sport fish to catch a 1.5 month ban really hurts.....especially when we're not even the cause of the problem.

 

Spatial closures to protect spawning aggregation sites are fair enough to be closed to all but the rest should be open to recreational anglers considering our share of the catch is small by comparison.

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Before this get's into a political name calling match and members slagging off each other let's just remember the political closed season. Only until tomorrow anyway guys ;)

As sad as it is, unfortunately politics is a part of recreational fishing these days.

 

It's important to be politically aware of issues effecting recreational fishing otherwise the greens and politicians will continue to prey on our collective apathy.

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As sad as it is, unfortunately politics is a part of recreational fishing these days.

 

It's important to be politically aware of issues effecting recreational fishing otherwise the greens and politicians will continue to prey on our collective apathy.

 

Completely understand Nanman and I agree it has to be discussed and understood.

 

We're just trying to get some of the old excitement over getting out and actually fishing back into peoples blood and steer away from some of the attention seeking bickering that tends to go on in these topics.

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Nanman
I know this has been said ad nauseum by many in the past but I think punishment should be targeted at the perpetrators or causes of the problem which is clearly the commercial sector.

In a state that's very light-on for quality decent size sport fish to catch a 1.5 month ban really hurts.....especially when we're not even the cause of the problem.

Spatial closures to protect spawning aggregation sites are fair enough to be closed to all but the rest should be open to recreational anglers considering our share of the catch is small by comparison.

 

 

 
One has to keep in mind a few things here;
 
- Belatedly, in the last year or two there actually was action taken to reel in commercial extraction (eg Gulf daily limits and hook number reductions). However there have been no additional new input or output controls implemented for the recreational sector (the non-charter component at any rate)
 
- The 6 week closure applies to all sectors, the aim being both to limit extraction and, perhaps more importantly, to minimise disturbance to spawning aggregations wherever they may occur during this period.
 
- The additional 6 week spatials closure also applies to all sectors, specifically to minimise disturbance at identified aggregation hot spots.
 
- Given recent changes in commercial extraction quantity, caution must be exercised when asserting that the rec component is small by comparison. It would not take much, given my first point and recent reductions in pro totals, for the rec component to be upped when the latest RFS results are known - for historical background, arising from the 200/01 NRIFS the rec snapper take was assessed at 42%.
 
- There is no suggestion (yet!) of a possession limit on snapper.
 
- SA is not the only state with extended species-specific closures.
 
And here`s an interesting one - [disregarding the reasons for the pre-existing Nov complete closure] - assuming there is an identified problem (regardless of how it was caused) does that then absolve a 20% (potentially say a 30%) contributor to ongoing extraction from any obligations to be part of the solution, purely because of that contributor (potentially arguably) not being the major cause of the problem?
Particularly given that the minor contributor is not being impacted by any newly implemented additional controls outside the closure period?
 
Cockles and lobbies extraction share by recs is arguably verging on inconsequential - snapper perhaps not quite so...
 
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Wholly cow look at the increase in northern st Vincent gulf.

 

I know this has been said ad nauseum by many in the past but I think punishment should be targeted at the perpetrators or causes of the problem which is clearly the commercial sector.

 

In a state that's very light-on for quality decent size sport fish to catch a 1.5 month ban really hurts.....especially when we're not even the cause of the problem.

 

Spatial closures to protect spawning aggregation sites are fair enough to be closed to all but the rest should be open to recreational anglers considering our share of the catch is small by comparison.

 

There is a bit more to this issue than just rec v pro.

 

Some pro fishers also lost out. What changed was the fishery went from by and large a handline fishery to a longline fishery. My workmate (an ex handline snapper commercial) was made financially untenable by the longliners so he handed in his licence.

 

The best data is on page 27, figure 3.1.a in the below link referenced by kon in his attached images.

 

http://www.sardi.sa.gov.au/__data/assets/pdf_file/0008/210050/Snapper_2013_Fishery_Assessment_Report.pdf

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The thing is that it`s somewhat dated information re commercials, if you superimpose the actual 2014 SAR figures there is an obviously declining pro catch.

 

As far as "only two data points" for recs are concerned - those are the recfishing surveys, and for better or worse that is what advises management decisions and sector allocations. Unfortunately this is the only source of formal or "official" information available to PIRSA...or whoever...to inform any directions or positions.

 

And as I have said in a previous post, there may (or may not) be a nasty surprise for recs arising from the latest recfishing survey in terms of extraction percentage.

;)

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Can hardly call it a trend when there is only two points of data.

Can hardly call any trend from the quality of SA's rec fishing data as already discussed. It simply doesn't exist.

 

 

That is not PIRSA's position, who afterall are responsible for publishing this data.  The differences between the Commercial and Recreational catches of Snapper are very clear as the graphs show.

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Can hardly call it a trend when there is only two points of data.

Can hardly call any trend from the quality of SA's rec fishing data as already discussed. It simply doesn't exist.

 

 

That is not PIRSA's position, who afterall are responsible for publishing this data.  The differences between the Commercial and Recreational catches of Snapper are very clear as the graphs show.

 

 

Well if that data didn't come from the rec fishing surveys where did it come from? Have there been some third party scientific assessments carried out in SA without public knowledge or something?

 

The reason why I ask is despite declining recreational fishing participation between the 2 'known' surveys, recreational caught snapper supposedly increased in 2007 compared to the previous survey. Section 5 page 3.

 

 

Snapper Total numbers of Snapper caught increased by 17% from 333 000 to

384 000 fish, with similarly very high release rates in both years (74%). The

recreational harvest (97 000 fish or 177 tonnes) comprised 19.3% of the total harvest

weight;

 

 

http://www.pir.sa.gov.au/__data/assets/pdf_file/0005/123539/A618891_South_Australian_Recreational_Fishing_Survey_2007-08__3_.pdf

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nok
The differences between the Commercial and Recreational catches of Snapper are very clear as the graphs show.

 

 

 
As I previously indicated, the graph from the RFSA site (April 2013 from memory) has now been supplanted by the SARDI 2014 SAR (for commercials at any rate), and the rec extraction...toss a coin...to be advised.
 
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nok
The differences between the Commercial and Recreational catches of Snapper are very clear as the graphs show.

 

 

 
As I previously indicated, the graph from the RFSA site (April 2013 from memory) has now been supplanted by the SARDI 2014 SAR (for commercials at any rate), and the rec extraction...toss a coin...to be advised.

 

 

Kon, one can attribute any claimed increase in rec snapper catches between the two surveys to the shift in rec effort moving offshore to boat based fishing. Page 3, section 4, bullet 2.

 

 

Fishing effort The number of fisher days decreased by 42% from 1.8 million in

2000/01 to 1.01 million in 2007/08. The percentage decline was greater with

increasing distance from the Adelaide SD and was most pronounced in the

freshwater regions of the state. There was a much greater decrease for

shore-based effort (55.9%), than for boat-based fishing (18%).

 

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TB
The reason why I ask is despite declining recreational fishing participation between the 2 'known' surveys, recreational caught snapper supposedly increased in 2007 compared to the previous survey. Section 5 page 3.

 

 

 
This is where it gets a little tricksy. Numbers or weight? Or should that be...supposed weight...
 
Note the sentence in the first para on p3 of the attached.
 
"It was assumed that the size structure of the fish taken by recreational fishers was the same as that taken by the commercial handline fishers in the same region..."
 
And this 2005 follow-up gives 115,000 harvested by recs - yet the "re-analysed" data for 2000/01 in the 2007/08 RFS states there were 85,000 harvested. As compared to 97,000 in 07/08.
 
Except, the 2005 re-appraisal of the 2001 NRIFS ascribes a weight of 3.6 kg per fish...but it`s only 1.8 kg per fish in the 07/08 RFS.
 
Confusing, much?
Have I missed something?
 

SARDI 2005 Snapper re NRIFS.pdf

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I note the statement "projections performed by the chairman of Recfishsa" in your original post above that graph.

 

Please explain?

 

I showed the graph given by the Chairman of Recfish SA, where he plots the weights of snapper caught by reccos.

Yes, I assume these values were from the 2000/2001 and 2007/2008 surveys, and on checking appear close to the values stated.

Your value for 2001 is not correct according to the original survey.  I have not misled anyone, and the graph was produced by Recfish SA.

I am unsure what I have to exactly explain.  I just thought the graph would be useful to reccos.

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I note the statement "projections performed by the chairman of Recfishsa" in your original post above that graph.

 

Please explain?

 

I showed the graph given by the Chairman of Recfish SA, where he plots the weights of snapper caught by reccos.

Yes, I assume these values were from the 2000/2001 and 2007/2008 surveys, and on checking appear close to the values stated.

Your value for 2001 is not correct according to the original survey.  I have not misled anyone, and the graph was produced by Recfish SA.

I am unsure what I have to exactly explain.  I just thought the graph would be useful to reccos.

 

 

The term 'projections' has no place in historical data. A 'projection' is a term used to guess future trends based on existing trends and anticipated variables.

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TB
The reason why I ask is despite declining recreational fishing participation between the 2 'known' surveys, recreational caught snapper supposedly increased in 2007 compared to the previous survey. Section 5 page 3.

 

 

 
This is where it gets a little tricksy. Numbers or weight? Or should that be...supposed weight...
 
Note the sentence in the first para on p3 of the attached.
 
"It was assumed that the size structure of the fish taken by recreational fishers was the same as that taken by the commercial handline fishers in the same region..."
 
And this 2005 follow-up gives 115,000 harvested by recs - yet the "re-analysed" data for 2000/01 in the 2007/08 RFS states there were 85,000 harvested. As compared to 97,000 in 07/08.
 
Except, the 2005 re-appraisal of the 2001 NRIFS ascribes a weight of 3.6 kg per fish...but it`s only 1.8 kg per fish in the 07/08 RFS.
 
Confusing, much?
Have I missed something?

 

 

Hmmmm....weight based on such a small sample of participants and a 'reflected' comparison made by a scientist sitting at a desk?

 

And the order of accuracy is your honour :huh:

 

Stuff all and nuttin I am guessing?

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nok
Your value for 2001 is not correct according to the original survey. I have not misled anyone, and the graph was produced by Recfish SA.

 

 

 
I`m admittedly not sure what the "your" refers to, but the RFSA graph is technically "correct" based on the 2005 MSF re-appraisal - it certainly is not correct looking at the 07/08 RFS readjustment of the 00/01 NRIFS...which would have been, to me, more of an apples/apples approach, resulting in an approximately horizontal line at just under the 200 tonne mark for recs.
 
One would hope the information source chosen for the 00/01 amount in the graph was for a reason other than to merely cherry-pick "to advantage"...then again the 2010 SAR also mentions the 42% figure for recs!
 
To me, it would have been more appropriate to stick with the 07/08 RFS and go with about 153 tonnes for 00/01 and 177 tonnes for 07/08 - unless of course the average weight of rec-captured snapper was in fact halved from 3.6 kg to 1.8 kg over an 8 year period !!??
:huh:
And even then the number of fish estimated to have been caught by recs would have remained about the same, ie 85K > 97K.
Okay, let`s even use 115K > 97K, still within a bull`s roar given CLs?
 
The MFA (Development RFC predecessor) at around the same time actually came up with a draft position paper on snapper management including the graph below.
 
[And oops, my bad, the latest Snapper SAR was 2013, not 2014 as a I had stated!]

Capture.JPG

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I`m admittedly not sure what the "your" refers to, but the RFSA graph is technically "correct" based on the 2005 MSF re-appraisal - it certainly is not correct looking at the 07/08 RFS readjustment of the 00/01 NRIFS...which would have been, to me, more of an apples/apples approach, resulting in an approximately horizontal line at just under the 200 tonne mark for recs.

 
One would hope the information source chosen for the 00/01 amount in the graph was for a reason other than to merely cherry-pick "to advantage"...then again the 2010 SAR also mentions the 42% figure for recs!

 

I think you should exercise more restraint before insinuating someone has tried to misled readers.

 

The graph in question (see earlier post) was from an article written by Brenton Schahinger (Chairman, Recfish SA) on p11 of the Black Point Progress Association, Spring 2012 newsletter. You then presented a similar graph (from the MFA?) which had a substantially lower snapper recreational harvest weight for the 2000/2001 survey, deemed 'correct' by yourself and the Brenton Schahinger value 'dubious'.

 

Your position and conclusions however are unsound based on the published record.

 

Schahinger's 2000/2001 is correct (almost) based on available primary documentation.  There are only two published estimates, 371 and 417 tonnes.  Currently PIRSA uses 417 tonnes.

However your further comment

 

it certainly is not correct looking at the 07/08 RFS readjustment of the 00/01 NRIFS

 

 

is incorrect, as no re-adjusted harvest weight for the recreational snapper catch in 2000/2001 was calculated in that report. You "chose" to determine that value (153 tonnes), based on assumptions, which apparently are incorrect.

 

The point of contention is that the Henry & Lyle 2000/2001 survey calculated the recreational snapper catch at 371 tonnes (average fish caught 3.2kg, number 115,798).  The Fowler et al 2005 study you refer to re-calculated that to 417 tonnes (average fish caught 3.61Kg, number 115,801).  The latter is not generally available, so the exact reasons and supporting evidence for the changes are something I cannot comment on at this time.

 

Jones subsequently published the 2007/2008 Recreational Survey in 2009.  He determined the recreational snapper catch at 177 tonnes (average fish caught 1.81kg, number 97.010).  Jones then compared the 2000/2001 and 2007/2008 surveys by removing the interstate component from 2000/2001. The number of snapper caught in 2000/2001 now fell to 85,951.  However Jones made NO attempt to re-estimate the annual recreational harvest weight for snapper in 2000/2001.  More importantly the only value PIRSA use for the annual recreational harvest weight for snapper in 2000/2001 is apparently 417 tonnes, and that is as recent as 2013 [see Fowler, A.J., McGarvey, R., Steer, M.A. and Feenstra, J.E. (2013). The South Australian Marine Scalefish Fishery Status Report - Analysis of Fishery Statistics for 2012/13. SARDI Publication No. F2007/000565-8. SARD1 Research Report Series No. 747. 44pp].  At no stage or in any manner does Jones (2009) address the difference in average snapper weight between 2000/2001, or that in 2005 when the average was raised from 3.2 to 3.61kg.

 

The figure of 153 tonnes for 2000/2001 is not cited by anyone except yourself in that draft position graph. Your insinuation of "cherry-picking for advantage" not only lacks support, but is much more applicable to your own graph, for using a figure - 153 tonnes - which has no actual precedent in the literature.

 

Only PIRSA is in a position to elaborate further on this matter, and not individuals who lack access to the methodology and how it was implemented.  

 

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nok
 
- I most certainly did not insinuate that anyone was trying to mislead, read again what I wrote.
 
- How did you get "dubious" out of "technically correct based on" ?
 
- Your statement "no re-adjusted harvest weight for the recreational snapper catch in 2000/2001 was calculated in that report. You "chose" to determine that value (153 tonnes), based on assumptions, which apparently are incorrect." and the rest of your post dealing with that was exactly my point in my previous post.
ie my "assumptions" are based on trying to make sense of an anomaly whereby the average weight for a (rec) caught fish "fell" from 3.6 (3.2?) kg, in 8 years, to 1.8 kg.
 
I am missing something here...from the 2007/08 RFS
 
p57 - the overview explanation in relation to the re-analysis
p57.JPG
 
p64 - 2000/01 figures
p64.JPG
 
p39 - 1.82 kg mean live weight
p39.JPG
 
Finally, I did state
"unless of course the average weight of rec-captured snapper was in fact halved from 3.6 kg to 1.8 kg over an 8 year period"

 

 

...which means that effectively one of three things is applicable to this whole construct;
 
- the 00/01 catch tonnage is incorrect because the average fish weight was grossly overestimated OR
- the 07/08 live mean weight is incorrect because 1.82 kg is too low OR
- the average snapper weight, as caught by recs, reduced by 50% over 8 years.
 
So, to justify your position in terms of your scathing response to my last post - which one of the three is it?
If the last option can be categorically verified, then I stand corrected.
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People, this is what it boils down to.

 

Let`s take all the re-analyses, all the 3.2, 3.6, 1.8 kg weights as a given, whatever...but here`s the thing.

 

According to the 00/01 and 07/08 recfishing surveys, we caught about 150% more biomass in 00/01 than in 07/08, but a very similar number of fish.

 

Am I the only one who can see just a wee bit of an anomaly here in terms of what information it is appropriate to use, and for what purpose?

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...which means that effectively one of three things is applicable to this whole construct;

 
- the 00/01 catch tonnage is incorrect because the average fish weight was grossly overestimated OR
- the 07/08 live mean weight is incorrect because 1.82 kg is too low OR
- the average snapper weight, as caught by recs, reduced by 50% over 8 years.
 
So, to justify your position in terms of your scathing response to my last post - which one of the three is it?
If the last option can be categorically verified, then I stand corrected.

 

I am at a loss why you continue to engage on an issue where you are so clearly struggling.  

 

First, is it not a fact that you used the following phrase,

other than to merely cherry-pick "to advantage"

and its attendant implication, in relation to the 2000/2001 snapper harvest weight in Brenton Schahinger's graph?   And was that 'barb' merely invoked because "your" figure of 153 tonnes for 2000/2001 was not used, even though "your" figure is unsubstantiated and has never appeared in the literature?  So again how can anyone possibly "cherry-pick" when only TWO (2) values are available (417 or 371 tonnes), and are not greatly  disparate?.  It is inconceivable that anyone would be expected to use a value that does not exist (153 tonnes).  That you are unwilling to concede this very simple point, is extraordinary.

 

There was no need to 'muddle' your last response by including swathes of data Tables, since I presented all the relevant values in my last post.  So I am again at a loss to understand your need to repeat them?

 

When you write

How did you get "dubious" out of "technically correct based on

 

please re-examine your original post.  You wrote

but the RFSA graph is technically "correct" based on the 2005 MSF re-appraisal - it certainly is not correct looking at the 07/08 RFS readjustment of the 00/01 NRIFS

if this does not represent a clear challenge to the verity of the 2000/2001 figure, then we again have a problem.  From your initial decision to use the 'correct' word written as - "correct" - to the categorical statement "certainly is not correct".  You wrote it so please don't try to play word games to obfuscate.

 

You fail to acknowledge the significance of 2000/20001 data re-analysis in 2005 which produced the 417 tonnes estimate.  That means the 2000/2001 data was examined twice and provided similar values.  In contrast the 2007/2008 survey never re-analysed the 2000/2001 data in terms of weight or size.  You did that yourself without knowing anything whatsoever about the sample characteristics.  Instead, why didn't you use 3.6kg for the 2007/2008 survey rather than 1.8kg if you wanted a 'direct-type' comparison?  Is this not indicative of bias on your part to present values in a graph more suited to the outcome you desire?? Accordingly the critical question for you is - why do you believe the 2007/2008 snapper average weight  is more correct than that in 2000/2001 (also re-analysed in 2005)? I would like to read your justification.

 

My response was not 'scathing' but simply re-stated the known facts.  That you have chosen that interpretation suggests an aversion to be shown 'incorrect', or challenged on the unnecessary innuendos used.

 

I myself don't have to justify anything, no incorrect information was presented, and I certainly did not employ derision.  Nevertheless you now don't ask but in fact demand that it is necessary that I answer certain questions (as you state) to

justify your position in terms of your scathing response to my last post

Nonetheless, I will answer your question, since by the manner it is framed indicates a real lack of understanding regarding the issue.  I thought you may have some idea when you mentioned 'CLs' but apparently not.

 

Well here it comes

 

I believe the researchers involved in the 2000/2001 survey have most likely correctly estimated the average weight of snapper (3.2kg or 3.61kg) in the sample(s) collected.  Subject to the errors associated with any length to weight transformation employed.  I cannot absolutely confirm this without re-analysing the actual data.

 

I believe the researcher involved in the 2007/2008 survey has most likely correctly estimated the average weight of snapper (1.81kg) in the sample collected.  Subject to the errors associated with any length to weight transformation employed.  I cannot absolutely confirm this without re-analysing the actual data.

 

and the final question

 

the average snapper weight, as caught by recs, reduced by 50% over 8 years.

 

 

Sorry, this cannot possibly be answered, since absolutely no reliable data is presently available to make that type of declaration.

 

You asked the wrong question.  You needed to ask WHY.

 

However I thoroughly commend you on the use of the term 'construct'.

an idea or theory containing various conceptual elements, typically one considered to be subjective and not based on empirical evidence.

and therein lies the most reasonable answer to this conundrum.

 

 

 

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nok
Okay, I`ll bite one final time.
 
You wrote it so please don't try to play word games to obfuscate.

 

 

If that is your perception, then so be it, puzzled as I am in relation as to why you would think I am disposed towards playing word games.
From where I sit, I would suggest that it is someone else who gives every impression of going out of their way to engage in word games based on semantics and purported hidden inferences in anything I say.
And, very much as an observation rather than a compliment, seemingly very skilled at it too.
 
Instead, why didn't you use 3.6kg for the 2007/2008 survey rather than 1.8kg if you wanted a 'direct-type' comparison?

 

 

From my recollection we went through the exercise at the time on the basis that the 07/08 survey was the latest survey, which referred back to the 00/01 survey in basic detail, and given explanatory statements in the 07/08 survey it did not seem unreasonable to utilise 1.8kg.
 
Accordingly the critical question for you is - why do you believe the 2007/2008 snapper average weight is more correct than that in 2000/2001 (also re-analysed in 2005)? I would like to read your justification.

 

 

As above, based on statements in the 07/08 survey that

Apart from this [drop in/drop out] issue, the application of consistent methodology and analytical procedures means that the two data sets can be validly compared to identify trends in the fishery.

and

The SA commercial Snapper fishery currently reports their catches in terms of both numbers of fish and landed weights

Thereafter the 3.6 and 3.2 came up, and there has been headscratching ever since...because recs supposedly caught a similar amount of fish but significantly less by weight.
As I keep saying, a direct-type comparison of quantity caught is seemingly a little difficult to come up with if one insists on weight rather than numbers, given a supposed interim change in assessed unit weight.
 
That you have chosen that interpretation suggests an aversion to be shown 'incorrect',

 

 

That is an extremely presumptive statement, to say the least, and I will thank you not to psychoanalyse my personality on the basis of internet forum posts.
I have no issue with being made aware of new information or perspectives which may result in me "reconsidering my position" (to use the classic management line).
And why are you, on an escalating basis, now starting to resort to hammering me with adhoms?
 
or challenged on the unnecessary innuendos used.

 

 

I am getting rather weary of having to explain and justify to you what I post, but for everybody else`s benefit, if you are referring specifically to the "cherry picking" business;
- I have met Brenton, had dealings with him, am priviliged to have been included in a few initiatives, and I respect him for his dedication and effort,
- "cherry picking" per se is not necessarily a derogatory term because it can be a valid course of action if there is supportable information available to be utilised, and in this particular instance was (as it happens) used with facetious rather than malicious intent,
- I actually followed up immediately thereafter with what was actually a legitimising statement for RFSA utilisation of that data.
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Kon@

"cherry picking" per se is not necessarily a derogatory term because it can be a valid course of action if there is supportable information available to be utilised

 

Finally clarity emerges. Please read the following statement carefully

 

In any statistical context, cherry-picking always has negative connotations, because it subverts the normal goal of accurate analysis.

 

 

In a scientific setting 'cherry-picking' is almost akin to 'misconduct'.  However your lack of knowledge in this area (stated as a fact and not as a put down) allows you to actually believe 'cherry-picking' is sometimes "valid".

 

Whether you want to take notice or not, I am telling you that you are very wrong on this whole topic.

 

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Excuse me for butting in, but this discussion seems to be spending a lot of time in the detail of who's right and who's wrong, and not a lot about the snapper closure policy. Far as I can make out, the base problem is lack of rec fisher data, and how the very small existing sample can be used in any effective manner to guide policy. IMO, interpreting two rec fisher samples over 13 years (no matter how it's done) is hardly likely to result in any kind of usable outcome for decision makers.

 

nok -

 

If Kon is "very wrong on this whole topic", perhaps you'd care to set the record straight.

 

In your opinion, what needs to be corrected, in what way should it be corrected, and what conclusion(s) do you arrive at?

 

 

If anyone's interested, it's my belief that the collection of rec fishing data in SA is abysmal and always has been abysmal.

Until that changes, this kind of debate will be endless. Policy decisions need to be informed by more than a "finger in the wind".

 

RJ

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Here we go again
 
In a scientific setting 'cherry-picking' is almost akin to 'misconduct'. However your lack of knowledge in this area (stated as a fact and not as a put down) allows you to actually believe 'cherry-picking' is sometimes "valid".

 

 
I don`t suppose the word "valid" would have been used in the context of "ostensibly justifiable" as opposed to "with unquestioned integrity"??
 
This is a fishing forum for goodness sake, not a scientific presentations or debate vehicle, or a court of law, and due to the generally conversational style it is very easy to assail someone using pedanticism in relation to lack of perceived strict correctness....if one has such intent, of course.
 
And with respect to lack of knowledge, without for instance having a professional hands-on marine sciences and/or departmental management background, the logical inferential extension would be that the vast majority of people on here would not be in a position to make a post on any fisheries management matter as may be under discussion at the time...?
 
As previously stated, I have no issue with being appraised of any "new" information, perspectives or interpretations, but I object to being spoken to like an errant child, and I am certainly not enamoured of semantic point scoring.
 
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