Science behind the proposed closures

[hungry6]

I'm actually from a science background, but from a different field, LG, your blatant unsubstantiated assumption is bordering stupidity, I pity the thought, that a science student like yourself cannot see or view a debate from a different perspective.
Your assertion of the subject appears to be based on "facts", but there have been call for you to put forward the facts, which is yet to eventuate, until then, every words of your futile claims are no more than just that. Also when we are refering to fact, are we talking about tested citing from the Science Journals and not extract from someone unproven theory, or press release.
I've been trying to hold back from making further post on this subject. It has now gone to the point that you're trying to pull rank, by claiming your level of education over the number of well learned fishos on this site.
there is an age old saying that goes "Scientia est Potestas" and I'll bet my bottom dollar, that just about every fisho on this site knows a fair bit more than yourself on fish and their behaviour.

[lefty_green]

http://www2.dpi.qld.gov.au/extra/pdf...finfishery.pdf

This is a quote from the above webpage.

Fishery Performance
Appraisal of fishery in regard to sustainability The Reef Management Advisory Committee (MAC) holds significant concerns about the status of the Rocky Reef Fin Fish Fishery, in particular snapper. DPI&F have recently completed a stock assessment on snapper that indicates fishing mortality is currently too high to ensure longterm sustainability of the fishery. Researchers and modellers agree that the results from the stock assessment may be confounded by hyperstability issues in the snapper fishery, where good catch rates can be maintained regardless of overall declining stock abundance. Fishers
spend more time searching for fish to maintain catch rates, which is not reflected in the logbook information and makes catch rates appear constant. Figure 6 indicates that commercial fishing effort has moved northwards supporting a recent shift to new fishing grounds. This is further
supported by commercial logbook data, fisheries observer information and anecdotal reports from recreational fishers over the last 12 months indicating good catches have been occurring with an increased occurrence of larger individuals.

A recent snapper stock assessment by Allan et al2, which was based on data from all fishing sectors, provided support for the concern expressed to date. An independent review has supported the results of the assessment and confirmed the use of the stochastic stock reduction analysis model. Further data is required to validate some of the assumptions about the age structure
of the snapper population, which was sourced from surveys undertaken between 1993 and 1997 and will ensure greater confidence in future assessments.
There is still some uncertainty surrounding the range of impacts on the stock, particularly in relation to habitat changes and the size of the recreational catch. Results from the 2005 RFISH diary round may help reduce the uncertainty of the recreational catch.

Well worth a read. That took me 2 minutes to find. I'm sure if I searched a little harder the news wouldn't get better!

[seatime]

http://www2.dpi.qld.gov.au/extra/pdf/fishweb/rockyreeffinfishery.pdf

This is a quote from the above webpage.

Fishery Performance
Appraisal of fishery in regard to sustainability The Reef Management Advisory Committee (MAC) holds significant concerns about the status of the Rocky Reef Fin Fish Fishery, in particular snapper. DPI&F have recently completed a stock assessment on snapper that indicates fishing mortality is currently too high to ensure longterm sustainability of the fishery. Researchers and modellers agree that the results from the stock assessment may be confounded by hyperstability issues in the snapper fishery, where good catch rates can be maintained regardless of overall declining stock abundance. Fishers
spend more time searching for fish to maintain catch rates, which is not reflected in the logbook information and makes catch rates appear constant. Figure 6 indicates that commercial fishing effort has moved northwards supporting a recent shift to new fishing grounds. This is further
supported by commercial logbook data, fisheries observer information and anecdotal reports from recreational fishers over the last 12 months indicating good catches have been occurring with an increased occurrence of larger individuals.

A recent snapper stock assessment by Allan et al2, which was based on data from all fishing sectors, provided support for the concern expressed to date. An independent review has supported the results of the assessment and confirmed the use of the stochastic stock reduction analysis model. Further data is required to validate some of the assumptions about the age structure
of the snapper population, which was sourced from surveys undertaken between 1993 and 1997 and will ensure greater confidence in future assessments.
There is still some uncertainty surrounding the range of impacts on the stock, particularly in relation to habitat changes and the size of the recreational catch. Results from the 2005 RFISH diary round may help reduce the uncertainty of the recreational catch.

Well worth a read. That took me 2 minutes to find. I'm sure if I searched a little harder the news wouldn't get better!

yaaawwwnnn!!!!


that took me 2 seconds

[scaly]

Oh dear LG- Resorting to snippets of information unrelated to recreational fishing to try and bolster a pathetically weak argument?

Sounds like your 3 year stint at university was a waste of effort.

[Adamy]

LG... why are you doing this to yourself?? Who are you trying to convince? Us or yourself? Is it that you just like to fight losing battles? I dont think there would be any on here that are going to change their minds - go have a look at http://www.ausfish.com.au/forum/YaBB.cgi?num=1158050035 "scientists" concluded the fish were nearly extinct... but their research methodology was flawed.... if these "scientists" can get it wrong - is there a possibility that other "scientists" could get it wrong?

I just wonder why you would exert such effort into trying to convert the unconvertable. Theres an old adage - birds of a feather flock together - I suggest you find birds of your own feather - there you can squark and flap your "vegan politics" wings as much as you like and no one will shoot you down for it. You are indeed entitled to your own opinion... but to try and convince us??

Umm yes I remember... you are a uni student.... I teach uni... so I know what uni students are like - so I'll have to put it into simple English that you can understand.... GIVE UP!!

[jim_farrell]

Thanks for the heads up on the report lefty.

It also states that all rec figures are estimates!!!!!!

That GBRMP closures have increased commercial pressure on other fisheries.

That an increase in the practise of catch and release has effected harvest numbers in rec fishing. THIS IS A HARVEST REPORT ONLY.

It also states that yearly fluctuations occur in commercial harvesting of snapper, p. perch, yellow tail king, cobia, amberjack and sampson. Could this just be seasonal?????

Lastly no where do any of these reports state what percentage of the exsisting fishery is being harvested. Until that figure emerges,nothing you say will hold water.

It would appear that if a report states that catch rates are up, you will say we are taking to many fish.
And if catch rates are down, we have already taken all the fish.

You are bundling rec and commercial in together. You can't do that and get an accurate assessment. Not that I have an issue with commercial catch rates.

Keep digging buddy, you make our argument stronger with every post.
Jim

[lefty_green]

You blokes are dead set kidding yourselves. You wanted evidence, I provide evidence but you shoot it down. Typical "its not my fault" attitude. I just ask before you post stuff have a good read of the status report. The gish is that a recently completed stock assessment on snapper indicates fishing mortality is currently too high to ensure longterm sustainability.

Adamy you teach uni? Hopefully not a marine science lecturer. I'm no longer a student by the way. I have had a job using my degreee for 15 years. Not that that would matter to you.

Scaly unrelated to rec fishing?? the report states that half of all snapper caught are caught by rec anglers - how does this NOT relate to rec fishing. Are you not reading the same document as me???

Another quote taken from the status report
Total harvest from all sectors: approximately 720 tonnes (including 523 tonnes snapper,
140 tonnes pearl perch, 15 tonnes of teraglin jew and 35 tonnes of other rocky reef fin fish)
Commercial harvest: approximately 325 tonnes (including 200 t snapper, 65 t pearl perch)
in 2005
Recreational harvest: approximately 330 tonnes (including 280 tonnes of snapper and
50 tonnes of pearl perch — latest estimate is from 2002)

and those estimates of rec catches would be underestimated.

[Fisher_Boats]

Lewfty ..They wouldn't have a clue what reco's caught....As the others said...give up...go and talk to someone who wants to listen to you

Col

[lefty_green]

Col so they could catch more than 280 tonnes?

[scaly]

Deary me- You call that evidence? Which online university did you use to get your credentials?

The increased catch rate for snapper may indicate the success of an increased minimum size
limit for both species that was introduced in late 2002. Given that the majority of fish harvested
in the fishery are two to three-year-olds, and that the increased size limit has been in place for
three years, it is expected that the positive effects of the change would be evident currently.

However, the increased catch rate may also reflect changing fleet dynamics, with some
operators more focused on targeting rocky reef fin fish, particularly following the introduction of
the Fisheries (Coral Reef Fin Fish) Management Plan 2003 and the rezoning of the Great Barrier
Reef Marine Park which increased the extent of areas closed to commercial fishing. Spatial
commercial catch information indicates that commercial operators have targeted new areas in
recent times. In many fisheries, elevated catch rates are often seen when fishers start fishing
new grounds.

Well looky there- No-take zones have increased pressure on other areas- gee, who woulda thunk it

I also see evidence that size limits are working for the particular species mentioned. Now in your great wisdom, how would you tackle the threat to snapper in this region?

and those estimates of rec catches would be underestimated.

With every post you make, you come up with some wild unsubstantiated assertations- You should be ashamed of yourself, being from a supposedly scientific disipline.

[Fisher_Boats]

Lefty ..You put whatever figure you want on it .. They are all just a guess.
as I said no one really knows including you [smiley=zzz.gif]

Col

[lefty_green]

Exactly - size limits are working. And thank goodness the bag limit went from 30 to 5. Remeber the furore on this site when they were being introduced? Yes the figures are improving BUT the whole point of my posts on this thread is that rec fishing contributes to the decline in fish stocks. That has been my point right from the start. And its true no matter what is said here. Snapper have come back from the brink due to the regulations brought in over the last few years - the bag limit of 5 and the increase in size limit has meant that snapper fishing has improved. Also bear in mind that alot of the posts on this site regarding snapper have come from 'the hards' an area not fished alot before last year? So it may look like alot of big fish are being caught, but they are being caught from a new, more remote area.

It was drastic measures because the stock was stuffed. Didn't the bag limit decrease from 30 to 5 mean the stock was over fished. Overfishing contributed to by rec fishers. What about when the limit goes to 2?
Deary me- You call that evidence? Which online university did you use to get your credentials? Nice one scaly - typical cheap shot from a coward.

Also the reason I say they are underestimated is because it is 2002 data. I would have thought that there has been a significant increase in the number of rec fishers in the last 4 years. A fairly safe assumption you would have to agree? i wont ask what an assertation is either?

Col I wont respond to that because we both know no matter what I say you wont budge.

[Fisher_Boats]

Lefty Quote
Also bear in mind that alot of the posts on this site regarding snapper have come from 'the hards' an area not fished alot before last year? So it may look like alot of big fish are being caught, but they are being caught from a new, more remote area.

What a load of bs!!!! What are you saying ..the hards was only discovered last year and all of these ausfish people are going to fish it out

Col

[scaly]

I have no idea about what went on on this site- I am a relative newcomer- but bag limits are working are they not?

Yes the figures are improving BUT the whole point of my posts on this thread is that rec fishing contributes to the decline in fish stocks.

I'll try and put this as nicely as possible: Well, DUH! Having an impact on fish stocks does not automatically equate to overfishing. Tempering bag limits is an acceptable solution considering the inexact science of fisheries and recruitment.

Also bear in mind that alot of the posts on this site regarding snapper have come from 'the hards' an area not fished alot before last year? So it may look like alot of big fish are being caught, but they are being caught from a new, more remote area.

Now why would that be? Wouldn't be displaced fishing pressure would it?


*edit* Just for you LG http://dictionary.reference.com/sear...ation&x=47&y=7

Nice one scaly - typical cheap shot from a coward.

I was being nice! I was going to suggest it might have been a Weeties packet but thought the online uni comment gave you more kudos

[Adamy]

LG... the so called evidence you presented was full of holes!! If the methodology is flawed then the results obtained must be similarly flawed. There is no true way to estimate the recreational catch rate.

Have you ever been fishing LG? Have you ever caught a snapper? Have you ever been out and not caught a snapper? Fishing is hit and miss at best - getting a few diary entries and extrapolating that across the estimated number of fishos wont work - neither will extrapolated phone survey - what was the methodology behind those surveys? - how was the sample obtained and how do we know the sample wasnt biased. If they used fishing clubs - where the average ability and effort per angler is higher - then results will be biased. Also estimating rec catch rates by extrapolating charter boat catch rates wont work either - why? because what is the proportion of charter boats to other non charter fishing activities? How would you obtain that info - do you count boating registrations? What is the proportion of sailboats to fishing vessels and other pleasure craft? How often to the purely fishing vessels hit the water and how often and how many fish does each boat catch per outing? What proportion of fishing only vessels solely target snapper and what confidence interval do you use for this assumption? Did you include the times the fishing vessel was used for family boating/camping and wasnt involved in fishing activities? Did you count fishable days during the year? and seasonality? Again - what confidence intervals were used? - anything less than 90% means that 10% of your results could be due to error. a 10% allowance for error means that your quoted catch rates could be out by more than 28tonnes - thats a lot of snapper!!!

Heres a small exerpt from Allen et al.: 2004.

There is substantial uncertainty in the landings estimates and no way to fully validate the assumptions made in our estimates.

Further more the article to which you refer says about the pearl perch estimates:

However, due to the survey methodology and because of the smaller number of pearl perch caught compared with other species the data should be treated with caution

In short you just cant be sure about your recreational catch figures, there are too many variables. Be very careful when quoting statistic as "facts" that are subject to so much variation.

In any case, the article which you so freely quote does not advocate increased closures and no go zones, it advocates management through increased size limits and possibly reduced bag limits (I added the reduced bag limits part as an alternative to closures)... Any which way you want look at it LG - the article in question doesnt help your case at all... so..... just give up pleaase!!

Oh by the way LG - I teach business statistics and quantitative analysis at university level. Do you need any more comments about your so called "facts"?