"I did state that we should declare our waters a protected wilderness"..I would guess that a "protected wilderness" would exclude ALL forms of fishing..or are we being selective..amateurs only allowed?
"australia is full of examples of wonderful ideas gone wrong"...Australia is also full of wonderful ideas that have gone incredibly right.
Why not feed farmed fish others items other than fish meal...simple solution.
Kerry,
I'm unfamiliar with this proposal (I'm a mexican) but were they oceans cages?
If so, I mentioned earlier that facilities need to be land based to protect the environment. I too am not a fan of ocean facilities, however, aquaculture setups that draw fresh water from the ocean are a good thing provided that the water is treated in accordance with the many regs (Which include bio filtration, UV sterilizers, settling ponds, etc) in place before being returned to the environment..
Nath...
I am for the farms,no doubt there will be teething problems along the way and untill it is all sorted it may very well be a case of choosing the lesser of the two evils.Fish in farms have to be fed fish meal if they aren't the product does not resemble the taste of what is perceived by the general public as real fish.
Nath, yeah they were sea cages within Moreton Bay but as usual the normal contradictions are put forward for approval.
As for land based shows well todate they haven't exactly been the pinacle of proving they are inert, long way from it with respect some of the affects on both land and water.
As for this feeding regime where one puts in more than one takes that well that has absolutely no sustainability what so ever in any way shape or form. Take the pilchard debacle for example and what apparently turned into an introduced desease that basically wiped out the pilchard stocks. That's simply one example of unstainability and greed at any cost.
Cheers, Kerry.
Did a quick seach on fish meal. Not an oz example but most of it is used for land animal feed.
http://www.feap.info/home/FAQ/Answers/ans7_en.asp
Kerry,
Please stop posting the same mis-informed information. Your rates of 5:1 are far out-dated. For example FCR values as low as 0.78 have recently been reported for barramundi (Williams et al 2003). This is not to say that they actually make more food as the pellets are dry, but the fish is weighed wet.
It is a simple fact that fish require more inputs than growth. It is very simple biology that food inputs are used for growth and metabolic stasis, which is incidently common to all primary industries.
The problem here is that the fish that are of large commercial importance in Australia are high up in the food chain. That means that they are not adapted well to digesting plant material (short guts, lack appropriate digerstive enzymes, bacterial flora etc.). Therefore they are traditionally fed foods with large amounts of fishmeal. As it has become evident that this is not sustainable, a lot of research has gone into optimising the utilisation of fishmeal for growth (minimising its use for energy) and replacing fishmeal with plant and terrestrial derived protein sources. For plant materials this involves a lot of processing to remove antinutritional factors and increase digestibility, but is sucessful in replacing significant amounts of fishmeal in fish foods (37% replacement of lupins by protein % without reducing growth or FCR; Glencross et al. 2004). Bloodmeal and offalmeal can be (and are commercially being) used to further reduce these figures.
So if we considder that fish are about 60% moisture, the dry weight to dry weight ratio is about 0.78g food: 0.4g fish growth, or a dry weight conversion of 1.95. So using 37% lupin meal to replace this fishmeal protortion of the diet to 29% (Glencross et al 2004), and the fish:fish conversion is 0.23g fishmeal : 0.4g fish growth. Therefore it is achievable to grow more fish than the fishmeal input by about 1.74 X.
These are real figures, derived from peer-reviewed international journals. Unfortunately feed companies will not tell us the actual proportion of fishmeal and alternative protein sources that they do use, but I can tell you that fishmeal is very expensive when compared to lupins and other terrestrial protein sources. If economics do rule, then feed companies will be replacing the maximum amount of fishmeal with alternative protein sources that they can.
I agree that it is a concern that large amounts of fishmeal are used by aquaculture, but the situation is improving rapidly and it is important to be up-to-date when throwing figures about.
....Well how about the fact that in general it takes something like 2-3kg of feed (fishmeal etc) to "grow" 1 (yes that is one) kg of farmed product and in some cases it can be much more at around 5kg plus....
Please stop posting the same mis-informed information. Your rates of 5:1 are far out-dated. And Leo please quote what your quoting in full instead of the typical selective numbers some of you people try to imply.
So Leo what specific fishery are you quoting those figures for? as yes there are fisheries aound 2:1 (as I previously mentioned) and then are others that are higher, right?
Now are you saying there is NO FARM FISHERY requiring higher feeding regimes
Does get rather interting Leo when numbers can be turned into just about anything anybody wants. As for weight well the real world scenario is at the fish counter, the weight one pays for, hey?
Cheers, Kerry.
[quote author=Kerry link=board=General;num=1112220819;start=20#21 date=04/01/05 at 13:59:26]
Whoops
Sorry, missed the quote bit, but you got the message anyway. You need to be clear what you are referring to, whether it be food, fishmeal, protein etc - they are all very different things. My previous post was an attempt to standardise the values so that you can understand them. Your original statement (that you quoted above) actually states "feed" which is in most cases the dry pellets. Therefore the values you are looking for are between 0.75-1.2 rather than 2-3 and up to 5. I can quote much more literature to you if you want.
I may be missing your point, but is the question "are there higher food conversion ratios currently used in aquaculture today?" ???
Tuna "ranching" is sometimes called aquaculture, and they do have much higher FCR's. Other than that I have not seen a literature value of a fish FCR > 1.5 in the last 5 years (other than those fish intentionally compromised for the sake of the experiment). If you convert this to a dry weight to dry weight ratio, this is about 2.5 g food for 1 g fish growth. There would have to be >40% fishmeal in the diet for a net decrease in the amount of fish produced compared to fishmeal used.
So Leo let me see if I have this right?
When you are referring to "feed" you are not referring to everything they "eat" to make them grow? So "feed" is just pellets, what sort of pellets?
So what do we have to do here Leo add up the "feed", the "food", the "fishmeal", the "protien" etc etc
Hope we don't have to get bogged down in the anti-biotic saga denial, again! especially the PR "wording"
Cheers, Kerry.
Are you serious Kerry?? I'm trying to give an informed opinion here, backed up by rigorous research. All that I get from you is entirely uninformed and incorrect opinions. It seems that you are particularly fixed in your opinions whether they have any basis in reality or not.
Leo, For someone "associated" with the industry, that has an "interest" in the industry and comments that are generally "from within the industry" and would probably rely on funding from the industry for "research" etc your comments could tend to be seen as very one sided, but about par for the course, considering.
It's rather amusing that anybody against some activities are always apparently ....uninformed and incorrect opinions.... funny that, hey.
Cheers, Kerry.
I dont know much on fish farming but wouldn't better than 30 trawlers headeding out in the bay for a couple of days. These trawlers should be cashing in there licences and buying into fish farm surley with the price of desil and insurance each year. For such a small return trawling the damage that the are doing is so high.
Mark
Hey Markwith all the so called build up with fish farms one should probably be buying all the trawler licences in sight, like fish have to eat too, don't they, no matter where they live
Cheers, Kerry.
Leo,
Thanks for your factual input into this topic it's always good to see relivant data presented in a logical way that most people can understand.
Kerry,
Thanks for giving me something to read... If you look up "arguement" in the thesaurus I think you will find 10 different photos of yourself
Nath...
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