Discarded Fish

[big_cod]

Thank you doc ,and leon .

[The doctor]

Hello Doc

 

Do you think that fishermen that fish in such a way that they eliminate any discards should be rewarded, more days or quota?

 

Hi Peter

 

A difficult one this, might sound simple, but to my mind its not that straight forward!!!!!

 

Hypothetically speaking; if you are a 16m beam trawler towing 7m v-rigs and your sole discards are 30%, and using techical measures to reduce your discard rate, lets say to less than 10% (I don't think in trawl fisheries that it is possible to totally eliminate discards), you are reducing the impact of your activity. However, given that in certain conditions (shallow water and moderate tow duration) survival of released sole can be relatively good (25 - 35%+), so in actual fact your overall benefit is a reduction in mortality on sole of 15% per day. I don't know what a 16m beamer targetting sole, can reasonably expect to catch in a 24hr period, but if we say (hypothetically) 200kgs, of which 30% is discarded leaving a landable catch of 140kgs (4 boxes), 60kgs is discarded of which 20kgs survives which equals a loss in sole biomass of 180kgs.

 

If by implementing technical measures that reduce the same discard catch by 20%, we are still looking at a landable catch of 140kgs, discards of 20kgs of which 6kgs survives which equals a loss in sole biomass of 154kgs, an overall saving of 26kgs of undersized sole.

 

If you give an extra two days a month to a vessel for implementing these measures to reduce discards, then the increased effort, landings will almost outweigh the benefit, but even more so in that a greater amount of spawning fish or fish with the potential to spawn are removed from the SSB, the increased effort would also affect other species caught as bycatch (plaice, lemons, brill, cod and rays).

 

So I'm not totally convinced that a reduction in discards coupled with an increase in effort/quota would be that beneficial, although that is not to say that fishermen should be discouraged from improving fishing practice and any impacts of their activity. Where there is real identifyable benefit with no discernable knock on impact, I would agree that mitigation measures such as more days at sea or increased quota for certain species may fully justify the end. Of course I may be way out with my figures wrt just how much such a vessel might reasonably expect to catch, do you have any better idea on likely catch.

 

I would have similar concerns over similar proposals within the static gear fishery unless there were suitable increases in MLS for all target and likely bycatch species, as you will know, there is no one-size fits all solution, a suite of measures are required, not the least, better prices from the first sale of fresh fish.

 

Cheers

 

 

 

Doc.

Edited April 4, 2006 by The doctor

[wurzel]

Hello Doc

 

All I know is that with a small rise in mesh size I can more or less eliminate sole discards, by avoiding a couple of areas I can eliminate any plaice discards.

I am sure trawlers can do the same.

 

Most UK North sea sole boats are small low impact and under 10 meters,

Why should they be tied into the same management as a Duch 40 meter beam trawler.

 

So what do you consider sustainable fishing?

How should it be implimented?

[steve good]

Hello Doc

 

All I know is that with a small rise in mesh size I can more or less eliminate sole discards, by avoiding a couple of areas I can eliminate any plaice discards.

I am sure trawlers can do the same.

 

Most UK North sea sole boats are small low impact and under 10 meters,

Why should they be tied into the same management as a Duch 40 meter beam trawler.

 

So what do you consider sustainable fishing?

How should it be implimented?

 

hi peter

 

they should be worried about bass discards after all they are putting up the mls for bass to 45cm without doing any research WHATSOEVER on bass discards.

 

was up at whitby the other day talking to ivor noble i think you may know him

[wurzel]

Hello Steve

 

Quote

was up at whitby the other day talking to ivor noble i think you may know him

 

Yes I know Ivor, good fisherman, not much he does not know about the inshore grounds of Whitby.

[Leon Roskilly]

they are putting up the mls for bass to 45cm

 

 

Is that official?

[Leon Roskilly]

hi peter

 

they should be worried about bass discards after all they are putting up the mls for bass to 45cm without doing any research WHATSOEVER on bass discards.

 

was up at whitby the other day talking to ivor noble i think you may know him

 

 

Netting is fairly selective in the size of bass being taken, so with an appropriate increase in mesh size discards shouldn't be a problem

 

The problem is with trawling.

 

 

Now lets say 10,000 tonne of bass is taken by nets currently, of which 5,000 tonne is between 36cm to 45cm

 

and 10,000 tonne of bass is trawled of which 5,000 tonne is between 36cm to 45 cm

 

So that's 20,000 tonne of bass being killed.

 

 

 

The mls is raised to 45cm

 

Now only 5,000 tonne is taken by nets

 

10,000 tonne is still taken by trawl of which 5,000 tonne is discarded instead of being sold.

 

So only 15,000 tonne of bass is now being killed.

 

 

A result for the bass, even if trawlermen are out of pocket.

 

 

(A dead fish is a dead fish whether discarded or sold)

 

 

Of course it won't quite be like that.

 

For a start inside 12 miles where the new mls will apply, far more bass are taken in nets than trawls.

 

Fishermen will adapt, and less bass small bass will be trawled, and the netters will take more bigger fish, but overall far fewer of the immature fish will be killed than at present, guaranteed.

 

Once the measures are in place, and fishermen have had a chance to adapt, maybe fishing a bit differently to now, and in different places, then is the time to do the detailed research and see what more can be done to cut down on trawl discards even more (more restrictions on where trawlers can operate, what gear they can use perhaps).

 

If the new revised mls (if that is what they go for) and the additional measures promised in Phase 2 are as successful as intended, I doubt that there will be many complaining in a few years time.

 

(Oh! alright, but fishermen are always complaining about something!! )

Edited April 12, 2006 by Leon Roskilly

[wurzel]

Hello Leon

 

It all sounds feasible, except for one thing, the French.

 

Quote

 

For a start inside 12 miles where the new mls will apply, far more bass are taken in nets than trawls.

 

Are you sure about that Leon?

[big_cod]

The pair team from scarborough are still doing well on the bass in brid bay.

Edited April 13, 2006 by big_cod