Science behind the proposed closures

[Fisher_Boats]

[quote=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 you 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!!



Geeze Adamy......That's what I said in one sentence

Col

[Gorilla_in_Manila]

So what happened to the tailor argument LG?
Seems we've left that and move on to snapper?

Cheers
Jeff

[Adamy]

Geeze Adamy......That's what I said in one sentence

Col

Yeh I know Col.... but this guy seems a little THICK!!

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?

Hey LG... Just checked your profile - you joined 390 days ago back in August of 2005 - you werent even a member in 2002 when the new limits were introduced (neither was I) - so what do you know about any furore????? I have just spent the last hour going through the archives and cant find the furore you mentioned. Are you making this up as well??? If so thats VERY NORTY young man!!!

Mate if you want credibility here - you had better put up or shut up!!

Adam

[jim_farrell]

Shall we leave this one to lefty. I think it has gone as far as it can go.

Lefty, thanks for the entertainment.

I'm done
Jim

[flathead_fred]

Lefty is taking a beating........ . Another reason academics use for creating areas that are closed to all forms of extraction is to study the natural densities, growth rates, mortality rates and ecosystem states in these areas. This can be important when trying to estimate the size of a population (extremely important to all forms of fisheries biology), as one of the factors considered in the equation is natural mortality, compounded by fishing mortality. At the momment natural mortality is calculated from populations which are considered pristine (nothing is pristine nowdays) or simply estimated using the available data. Maybe setting aside areas will aid fisheries management indirectly in that in the future they can act as a source population from which to base population estimates, fulfilling a crucial aspect of the popultion model equation. This could take upwards of 30 years i'd imagine.......too precautionary? Just a thought, i haven't posted for a while and thought some more scientific reasoning couldnt hurt.

Great stuff so far,
Mike

[Adamy]

Real scientific reasoning is welcome Mike - not that tripe that Lefty was coming up with. I stayed out of the whole debate - because I was enjoying what you were saying - it had reason and scope and helped me understand some of the supposed logic behind the arguments. But when I read his diatribe - I couldnt hold back any longer..... welcome back!

One thing that Lefty did elude to - and a fact that others picked up on was that when they close areas - Fishos being a fairly determined lot - go off in search of other reef - which has been relatively untouched to fish.

Why cant scientists find their own patch of reef to study instead of following fishos around and trying to steal their/our spots??

[lefty_green]

Gents
I can see that whatever i say I will be shot down. Usually I can see when I'm beaten and i give up but for some reason I kept pushing to my detriment. Can I just say this. Rec fishing does contribute to the decline in some fish stocks, tailor and snapper being examples. You will note that both of these species have had dramatic changes to bag and/or size limits in the last few years. Also you will note that there is a specific area that is closed to allow a significant proportion of the tailor stock to spawn without harassment. Spawning closures are now used on the reef as a tool to ensure sufficient spawning and recruitment of vital reeef species.

Yeh I know Col.... but this guy seems a little THICK!!
Adamy you obviously have strong opinions about my opinions but is this really necessary? You asked for evidence, I gave you the best available but you shot it down. I simply stated that rec fishing does have an impact on fish stocks. I made no comment about closing areas of Moreton Bay. I dont want to see 50% of the Bay closed - I would like to go fishing in my favourite areas. I am NOT for the closures - I was in fact trying to be the devils advocate, bringing up some points that I thought were worth discussing. Seems I was wrong? Oh well, I hope I provided food for thought and people reading these posts can realise that if we, as rec fishers, are to have a leg to stand on in the future with fisheries managers and greens, then its time to realise that we need to be able to defend our point of view with hard facts. At the moment we cant due to the so called evidence you presented was full of holes!! If the methodology is flawed then the results obtained must be similarly flawed. Bring in a licence, do the research to provide information for improved modelling of the rec fisheries. Its relatively easy for commercial fishing as they have log books which must be filled out.

I know when I'm beaten so I wont post again but I will read the "I told you so" and "get lost greeny" posts which i'm sure will follow. So post away. I hope there is a green streak in all rec fishers, I was just looking at things with my green streak in mind. Probably doesn't help with a moniker like lefty_green either, so apologies to those that wanted to beat me up. Its hard to believe but I'm on your side.

At the momment natural mortality is calculated from populations which are considered pristine (nothing is pristine nowdays) or simply estimated using the available data mate I'd be interested to know what species has their N estimated from pristine populations? I would think most N are estimated from catch and effort data or tagging data?

[Adamy]

Hi Lefty.... OK... now that it seems the sting has been taken out of your tail (so too speak)... we might be able to discuss things rationally. Personally I dont believe that anyone wanted to beat you up - least of all me. And I apologise for the "thick" remark - I was just trying to be funny to Cols remark.

You have to understand that the guys on this site know they know more about rec fishing and its impact than most of the greenie type hype (despite "scientific" evidence). They/we are sick and tired of having this crap shoved down our throats and told we are a bunch of environmental vandals and having our favourite zones closed. So when you try and support the "scientific" evidence for closures you automatically become a target. I apologise if it became personal... but for some of us it was an outlet to vent our views and as long as you were playing devils advocate (or Green advocate... who may as well be the devil as far as I'm concerned) then you were always destined to cop it - and yes especially with a moniker like lefty green.

I also dont think that anyone is really arguing about the effect of rec fishing on fish stocks - its simple maths - If I take 1 fish from the ocean then thats one less that you can catch... but then theres recruitment... which is a whole other discussion.

As part of another discussion; Licences dont actually help estimate the recreational catch - all they do is provide revenue (which is often used to regulate/police closures) what licenses can do is estimate how many fishos are out there (in possession of the licence), but they cant estimate how often the licence is used - i.e how many time the licensee goes fishing within that licence period and how effective they are during each outing - so they cant estimate catch rates... by any stretch of the imagination. So licences are not the answer to estimating the rec catch. Anyway, a 2005 DPI& fisheries survey, (but who knows how correct the findings were) found that the vast majority of rec fishos (or rather this group made up "the biggest group of anglers") were aged 5-14, this age is exempt from licencing laws - so the results of any estimation due to licencing, would be skewed in any case.

So from my end I will apologise once again for any personal remarks..... it definitely appears that since you understood what I said that you are not so "thick" after all.

I think the major difference between your style and Flathead's is that he tried to explain a position without defending it. Whilst you seemed to be supporting and defending the "scientific reason for closures" position. It makes a huge difference in the level to attitude you may face... I might face the same if I tried to present my attitude on a greenie/vegan forum.

Hope that helps explain the angst.

Adam

[scaly]

Bring in a licence, do the research to provide information for improved modelling of the rec fisheries. Its relatively easy for commercial fishing as they have log books which must be filled out.

As part of another discussion; Licences dont actually help estimate the recreational catch - all they do is provide revenue (which is often used to regulate/police closures) what licenses can do is estimate how many fishos are out there (in possession of the licence), but they cant estimate how often the licence is used - i.e how many time the licensee goes fishing within that licence period and how effective they are during each outing - so they cant estimate catch rates... by any stretch of the imagination. So licences are not the answer to estimating the rec catch.

And here is where I agree with you LG. Licences should be tied to a catch databook and it should be an offence to be caught fishing and not in possesion of one. This would improve greatly the data available for rec fishing, so informed decisions can be made. I also feel that they should be linked to an education program that would emphasise worlds-best-practice catch and release techniques and species identification, etc.

[Gazza]

Lefty (devil) you were EASILY out-debated ,in any requirement for RecFishos to be locked out of further areas of Moreton Bay


RFL is another topic/discussion NOT REQUIRED. *end-of-story*

http://nuggetfishing.com.au/Music/Track%2012.wma

[vapour_trail]

NO licenses,we pay enough in efn taxes,fishing licence revenue would not go back to fishing it would go to give the politicians pay increases,look what they did on tuesday 3 days after an election.

Work out the GST you pay on everything you use to go fishing that surely covers any licence.

cheers mickey.

[scaly]

Yes licences- either free or just enough to cover the cost of setting up a system of recovering data from rec fishermen and a more accurate gauge of total fishing effort. Not as a revenue raiser.

Work out the GST you pay on everything you use to go fishing that surely covers any licence.

It doesn't cover badly needed education nor will it return accurate catch figures that are needed by fisheries managers

[vapour_trail]

Yes licences- either free or just enough to cover the cost of setting up a system of recovering data from rec fishermen and a more accurate gauge of total fishing effort. Not as a revenue raiser.

Work out the GST you pay on everything you use to go fishing that surely covers any licence.

It doesn't cover badly needed education nor will it return accurate catch figures that are needed by fisheries managers

What sort of education do you think we need?
Fishermen gave concise information to G.B.R.M.P.A and this info was turned against them,I am suspicios of fisheries managers- some may have other agenda's.

I am happy for any measure that is of benefit to fishing and the enviroment however there is no acountability by politicians or public servants and wont be until fishermen have a political voice of there own,without it we will be a pushover.

[Gazza]

It doesn't cover badly needed education nor will it return accurate catch figures that are needed by fisheries managers

Hi Mate,
that's ANOTHER REASON for no rfl...... [smiley=guitarist.gif]

I've ALREADY got a DL/BL ,stuffed if I'm doing a logbook of where I go or klms travelled. [smiley=whip.gif] [smiley=beatnik.gif]

p.s. $$fine$$ me ,for overbag/undersize, no issue whatsoever

[scaly]

Fisho's on here and those that choose to self educate don't need much if anything- but there is a large majority of once/twice a year fisho's with no idea about catch care or awareness of the surrounding environment. Some of these guys are a bad advertisement for rec fishing and if a licence helps reduce that latent effort than it will be good for the fish IMHO.

MPA managers are a different kettle of fish to fisheries- although fisheries management Australia wide would need an overhaul to get away from the heavy bias to commercial fisheries.

I've ALREADY got a DL/BL ,stuffed if I'm doing a logbook of where I go or klms travelled

Thats your perogative Gazza- I disagree because I don't believe that attitude is in the best interests of the fishery. I didn't mention anything about km travelled.