Agree to at least 600mm and increase the limit to one per person regardless of anglers on boat 

What is the 500 based on now? Does 500mm give them 2 years of breeding before being legal? Do they slow down reproduction as they get older i.e. at 450mm are they like a randy 18 year old and by 600mm they're like a 50 year old slowing down? Definitely wouldn't mind catching bigger fish instead of a 500+ mm, perhaps a phase in i.e. next year go to 550mm, the year after 600mm until reaching the 650mm or so. At least with this approach I might be able to beat my pb of 10kg.

I think a gradual progression would be a good idea. I dont think are slowing down at 600 but could be wrong. Because of the slow growth rate we could assume that the teenage years are 650+ ? 

I dont think really it matters on how many years breeding they can acheive before the 500 limit. as we know there are plenty of small dhuies out there. It is more a size limit change i think.

Slam, great topic

 I have thought about your idea for many years now. I think it has merit, considering Dhuies of that size or smaller, have a better survival rate than large  Dhuies. Bigger Dhuies produce more eggs / sperm. But one thing is with noting that male Dhuies produce only enough sperm to fertilize 50% of a female dhufish eggs for the same weight - opposed to snapper which almost %100. Hence why there are more snapper and they recover from over fishing quicker.

 Slam,

the reason for the large population of sub 500mm we are seeing now was from a massive recruitment year 5-6 yrs ago along with the run of Crays we are currently seeing. I'm interested to see if the amazing run  of white Crays in the metro area carry's over to this year

Gunner

I agree to one per fisher on the boat, but only for fish between say 600 - 800.
Under 600 I find to be all head & not much flesh for the size.
Over 800 to left for breaders to sustain the future.
I know it's hard to release fish from a depth & most probably don't survive. But I have found that instead of trying to rip the head off & get it up quick, a slow wind up can usually result in no baratrauma with a successful release.

and biting my tounge ,self imposed moratorium is the way to go ,seems your already going above and beyond the science that is out there  

The question you have to ask first is, is 5 years enough time to see the effects of the demersal ban (which interestingly doesn't align with dhufish spawning times) to start looking at bringing in new rules?

I wouldn't be against a gradual increase if it were based on strong science as a 500mm dhu doesn't have a lot of meat on it but I will keep em however I won't keep a just size crab, flathead or tarwine as the meat you get isn't worth the effort.

 Wouldn't you rather have the opportunity to keep 600mm+ as the norm rather than just 500 with not much flesh?

 I dont think that u should give fisheries anymore lame ideas than they already have . If u wanna take fish over 650 then thats a personal choice thing . The size  limit should stay the same but one per license onboard is fair .

 Sorry but i dont think it is a lame idea imo. Just a thought on how to improve the fishery we already have. Always room for improvement!

Fishcrazy, are saying you want to increase the bag limit to one per licence & also keep the size limit the same? Seems like that is going backwards?

How about changing the bag limit from 2 to 3 Cat 1 fish.

I can live with 2 dhuies per boat, and 500mm is OK, but what about the days when dhuies aren't biting and all you get are breaksea, foxies etc. 2 fish is pretty miserable.

We sometimes get some nice red snapper, but after heading out 20nm bringing in 2 of them seems a bit light on.

Just my 2c.

I think whatever theyre doing is working.

We generally don't bring home any dhuys under 600mm. Theres definitely plenty of 500mm models out there but there is still plenty of big ones out there. Just don't get them every trip

think it's pretty well known that dhus don't release well.
so not sure whether it would be beneficial or not.

can imagine some heading out and catching (and releasing) 10+ dhus before getting a legal one if the size limit was raised to 650mm. how many of these would survive. Granted quite a few fishers...me included give (possible) dhus a deco stop and go easy but many many wouldn't. who knows what the survival rate of released dhus really is.
and then of course only bigger breeding stock are being taken instead of some smaller ones with ppl staying out until only the biggest fish are put in the eski.

Interesting thread though

 Leave it as it is.
Great in theory to raise the limit, but there will be more mortality from people releasing them wrong.

Obviously though the size limit must be ok if the amount and size of fish are increasing without doing anything except removing commercial effort.
I say dont go looking for problems to solve where there arent any apparent.
If anything dhuie limit should be changed to same as coral trout, 1 per sperson per day, maybe 4 per boat to avoid the mortality associated with releasing by people who dont do it right or dont try at all.

The greenies will make up plenty of rules to restrict your fishing, without any help!

 I per fisher per boat, max 4 per boat. I reckon the stock is good enough to cope with this. 

 I can't understand the reasoning of only taking the big ones when everything else in the ocean eats the small ones. Leave the number as is is but only keep a fish under 500mm. If you constantly remove the biggest survivors from a population you're selecting for the small ones. You're more likely to catch a small one because there's more of them and they won't die on release because you're not trying to upsize to a big one 

 told me (as Rob H said ) Because of the high mortality rate on Dhufish release, they are reluctant to increase the minimum size which would lead to huge numbers of Dhuies dieing on release. cheers Pete.

A lot of thoughtful comments coming across. My own view is that things should be left as they are for a couple of years more then some sound scientific well funded research should be carried out to ascertain just what condition the bio mass is in.

We have all pulled up fish that are just over the limit, it becomes a self regulation on whether you keep it or not. it also needs to be taken into consideration the fish will shrink marginally after its death and depending on how close it is to the size limit you could find yourself in a lot of hot water if the fish is measured later on by DoF.

Also as has been mentioned above do you really want to keep a fish that is going to provide a minimal amount of flesh for all the effort in filleting skinning etc.

We each have our own limit and 600mm is mine

 No way ! Crazy topic of discussion. Leave it to the fisheries scientists ! Yeah i may not catch the biggest dhuys out there and i agree that theres not much fillet on the 500 models thats why i let them go. this is a moral question that we each choose on our own backs. But i guarantee you there is plenty of horses out there. Friends of mine consistently catch 8-900+ models. If you not happy with catching only 5-600 models then maybe you should re-think about where you are fishing and re- assess the way you fish !!! 

 Ask the greens what to do!

 1 fish per licence holder leave the size limit the same. Plenty of fish out there. If you don't want to take the small 500 size then don't. Majority of times in my boat anything under 600 goes back anyway. 

 .......

 It's up to fisherman what they take . I somewhat agree with first post. I try not to keep ones 500 to 600 long. My choice . Limits and sizes there for a reason . People who make rules do it with a heap more understanding than us:):)

 I personaly believe it should be raised to 600 at least. We dont keep any under this size as the fish shrink 20mm on ice anyway. I dont think it would matter on the high mortality of fish if the size limit was increased. Its not like u can just stop fishing for dhuies, sure once we have our 2 on board we move to less likely dhuie ground but we still manage to find them. And yes there are still plenty of big ones out there. People need more education on bringing fish to the surface. U dont need to reel them up as fast as u can.

very interesting thoughts.  Obviously we can't know exactly how many do survive on release but if handled well you would hope a high percentage do. Does fisheries know that if increasing the size limit to say 600 would increase the mortality rate more so than at 500? It seems that many guys self regulate to 600 so would it be an issue if the limit was raised? 

I am not too sure on increasing bag limits is wise but I understand people do miss out if 2 already on board. Especially if that big one comes over the side! 

It is good to see other opinions

 Personally Id say that those who "self regulate" would be way more likely to take care of their fish when returning the smaller back down.
Average joe Bloggs, not.
Unfortunately in many places it is necessary to rip them up as fast as poss to avoid sharks.

My concern is that there are an abundant amount of small dhu under 500 and a limited amount over. Fish do not get chance to get over 500 due to size limit and still plenty of these go back down completely blown by fishers who do not know what they are doing. Example, last wk when out I pulled 11 undersized dhu up and 1 at 700mm. We kept on moving around to try to target something else but to no avail. Now if the limit was raised to 600 or 650 there would of been more fish around that size and we would have come in if a couple of 650's in the esky. Unfortunately with the up most care still a few I would say didn't survive and it is anyone's guess to how many actually did survive, maybe 50-60%?

Maybe more research is needed before any changes are made but I still think the dhufish population could be in trouble unless we are all happy to catch 500mm fish.

One fish/ per fisher/ per boat - max 4

Min size 600 or 650...500 is too small.

Resistant to high end size limit but respect the science regarding egg limit and biomass restocking.

Two 50cm fish by 7:30am only leads to people looking to spend the rest of the day upgrading until max size is achieved.

We need to motivate people to catch as few fish as possible and be happy to head back with a good feed.

4 men on the boat heading in with one fillet each from a 50cm fish...fish fingers for the kids!!!

what you have to take stock of is that the min size @500 was put there because they do breed under that size ,& dhufish due to their single blood haemoglobin , unlike many other demersals they do suffer much more with barotrauma upon release compared to other species that automatically puts their survival rates after release much lower that say snapper etc no matter how well there brought up and handled etc etc

yes they swim away/down well ,but that's only what we see and for many this visual helps them to believe more dhuies survive than die after release & gives some false sense of higher survival rates than actually exists

the 500 min size is the only size reg on dhuies for that simple reason , that allows anything above it to be kept and is designed to min the release of untakeable fish , below that which can still breed and maintain stocks if you where to bring the max up to say 600 or 650mm, while you would get to take home a bigger dhuie , all dhuies under that then must be released .. so increasing the limit to 600/650 mm will definetly increase the mortality % of all the dhuies under that that must then be released

 Is that proven research from fisheries that 600mm dhu mortality rates go up on release from a 500mm specimen? I can understand the large 800mm plus fish mortality rates will go up.

Would it be fair to say that the reason there is so many 500mm models around is because since the rules were changed the increased stocks are only just reaching this size, so increasing the size limit would not make any difference as it is only going to take time for these fish to reach the 600-650mm?

 Definately need to see if the large numbers of small dhuies are a result of changes in 2008 or just the fact that 500 is the legal size & most of the larger specimens are gone & anything over 500 gets taken.

A good example was a few yrs ago visiting a mate in the Sunshine coast. I think the snapper limit was 350mm at the time! Guess what, all we caught was a huge number of snapper that size & smaller which was why i posed my question at the start.

Hezzy quote (the point is that if you increase the min legal size up to 600 -650, no fish under that size can be kept , so they all must be released , that will mean a lot of fish in the size between 500mm up to 650, that could have been kept before would then have to be released , thus many more will die as a % of those 500-650 mm dhuies released)

If the limit stays at 500mm then most over that limit will die anyway due to them being kept so it doesn't really matter how they die i guess? 

Maybe just the fact more people out there fishing and less bigger fish around due to the pressure. Certainly noticeable over the last 5 yrs of larger fish coming on board for me. Maybe i am just losing my touch!!

well you have to factor in the significant increase across all areas on demersal and all fishing really imo compared to say 1980 or 1960

more people fishing now
bigger and better boats now
wider scope of travel by boaties across all our state
quality of sounders
quality of gps units
quality of chart plotters
improvements on gear and techniques
affordability of all of the above

it would be hard to argue there not under immense pressure sustainabilty wise compared to say 50 years ago
rec fishers need to be mindfull of that and thus apply caution & patience in how we manage the dhuie stocks into the future

hezzy

 Theres a lot of small models around but theres a lotta horses comin over the side to last 4 i caught all upper double digits thats over 3 months but there around .

First admission, i havent read the entire thread.

Second asmission, i dont threaten the fish stocks having only ever bagged out once (on pink snapper in shark bay).

To eleviate the argument of whether dhu fish survive release or not, consider the NT ideology of only keeping the first x number of dermasal fish landed per boat, no matter what species, no matter what size.  In theory that would eliminate releasing demersal fish altogether.  Catch your bag limit, come home.  Or troll (target pelagics instead for the rest of the day)

There is an argument against this and that is how to police the risk of "upsizing" releasing a smaller fish for a bigger fish.  I dont know the answer to that, other than huge penalties if you get caught.

Thoughts?