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Far side
16-01-2008, 11:16 AM
Did anyone catch the ABC program on top line predators last night?
The gist of the show was that by removing the predators from an eco system there was dramatic effect on the rest of the system.
There was a section on the fish reserves in Haiti where the fishermen had removed the large fish then focused on the graziers on the reef
Once the balance had been upset with a reduction of graziers on the reef this allowed the algae to take control of the reef and eventually turn this into a barren wasteland
The fishermen in Haiti were having to travel further and further a field for their catches and in most cases were catching nothing.
The consensus was that they shut down areas to all fishing to allow recovery, which they did. Later they were starting to catch larger fish on the inshore reefs and the fishing was improving. They also cycled the areas so that they could catch the larger fish up to a point then close again and move on.

It seemed to be working
They seemed to find a balance with this

Now dont jump on me it was just an observation I fish like everyone else and hate being dictated to by authority but some thoughts would be interesting particulary if you saw the program

mad_pierre06
16-01-2008, 11:33 AM
In principle i agree with the thought of seasonal and cyclical closures. But once the EPA has got their grubby little claws into any areas of interest, there will be no reopening.

dfox
16-01-2008, 11:53 AM
I'd like to think that the program (on fish) was telling the truth, but somehow it had that feeling of a propaganda film...

polky
16-01-2008, 12:10 PM
When they shutdown certian areas, fishos through no fault of there own flog what little productive areas that are left opened. Those areas are then turned into the underwater deserts that that show was referring to. It would be good if every couple of years they circulated these green zones, but they don,t. Fishing grounds become less productive,fishos start to take risks by travelling further offshore in little boats. Polky.

seabug
16-01-2008, 04:19 PM
Seems every fish has a purpose in the system

Some years ago the cray fishermen really hit the sharks in the closed cray season.
The next year the cray fishing was bad,Octopus everywhere eating the crays

So they left the sharks alone and they ate the octopus.
Things returned to normal

Regards
seabug

Nic
16-01-2008, 05:56 PM
There is one significant difference... on those fished-out islands they would probably have had little to no fishing regulations. With no size limits, bag limits or commercial quotas, people could have just kept every edible fish they caught. In Australia we (thank heavens) can't do that.

But if I learned anything at uni (which I sometimes doubt!) it's that if you remove an organism from the food chain, you get consequences. I think the doco was making a valid point in that respect. Still, it's not like the only solution available to us is to lock up colossal chunks of our coastline, no matter what the greenies might like to think.

FNQCairns
16-01-2008, 06:24 PM
Yeah I saw it, made me a little cranky the way they played it, almost as if normal fishing pressure and anything even remotly appoaching sustainable resourse use was part n parcel the cause, everything right up to poison would have been used to get the reef to that stage - the comparison is simply impossible to parallel here in any way but it is the entire ideological justification for why we here have lockout zones non the less.

Made me wonder what they didn't say over the Wolf story which I believed as plausable until the reef story perked my sensibilities.

Was interesting how they mentioned it was very hard to measure what effect the green zone was having and this was originally a piece of reef that would have been (was) open to the most systematic and non remiting abuse for generations and in the crudest possible ways.

cheers fnq

Far side
16-01-2008, 08:11 PM
I did note that the reef part of the story did reek of raping and when they did the pan back of the fish markets of a few small tables in a large shed that would have been in the past full of fish I thought these guys have buggered their fishing enviroment through no control and then in desperation even netting the smallest fish untill there was nothing then winging because there was no fish left

the wolf story however had a bit of common sence about it and seemed to be working at the expence of local farmers livestock

Nic
16-01-2008, 09:06 PM
In their defence, the guy did make a point of saying all the tourists were surprised the Jamaican fish were so small. That would imply that most of the developed world's fisheries are significantly better managed than Jamaica's.