A petition has been set up on the No.10 Downing Street web site, to ask the Prime Minister to increase the minimum landing size (MLS) for bass (Dicentrarchus labrax) to 45cm. This will allow all bass to spawn at least once during their lifetime and help establish a more sustainable bass stock, thus benefiting both commercial fishermen and recreational sea anglers. The petition also urges the UK Government to lobby the European Union to introduce the bass MLS in all Member States.
Please visit the No. 1O Downing Street web site and sign the petition. The deadline for signing is 28 March 2008.
Please do not forget to tell your friends, your local sea angling clubs, tackle dealers, not forgetting the hotels, B&Bs, boat chandlers, marinas, etc., in fact all those businesses, who rely on the recreational sea anglers for trade. Thank you.
If you would like to comment on this article, please contact BASS and if appropriate, we’ll add your comment below.
10 April 2007 – comment from Hippolyte of France:
In my opinion, among all the way-out assertions which are without any scientific base, there is one which particularly deserves denunciation. It is the assertion according to which, to preserve a halieutic resource, one needs a minimal size of capture that is at least equal to the size of sexual maturity of the species, so that all the fish have the possibility of reproducing at least once.
As far as I can judge, with the reading of various erudite works treating of the dynamics of fish populations, it seems to me that the size of sexual maturity never constitutes a very determining parameter in the eyes of the specialists who are interested in the stocks management. They take into account the age at first capture, the growth rate, the natural mortality rate and the fishing mortality in order to know if the exploitation of a fish population is made under conditions of “maximum yield per recruit” and in particular to know if there is no “growth overfishing”. They also determine the fecundity of the “spawning stock biomass” (in this determination only, the age at first maturity is of some importance) or evaluate the arrival of new individuals in the fished population (recruitment), to know if the population has the capability to remain at a constant level, i.e. to check that there is no “recruitment overfishing”. No correspondence between the size at first capture and the size at sexual maturity seems to condition in itself a “maximum yield per recruit” or “maximum sustainable yield”!
Then why this leitmotiv about a biological mesh that should make able all fish to reproduce at least once? Why the specialists in halieutic science do not definitively condemn this naive and fundamentally erroneous idea concerning the management of fishings? I would like to know…
11 April 2007 – comment from John Leballeur, Chairman, BASS Restoration Project Team:
Many thanks for your comments and observations. It is interesting that you should be well read in the standard texts relating to fisheries management and we respect your opinion.
From our perspective such principles of ‘maximum yield per recruit’ and ‘maximum stustainable yield’ are related to the commercial exploitation of fisheries (halieutic) resources and have formed the basis of fisheries management within the Common Fisheries Policy for the past 20 years or so.
Regrettably, most species that have been managed in this manner (to MSYs) have dwindled in both numbers and in size range. Indeed some stocks are now being fished on a recruitment basis and bass are fast becoming such a species.
The situation with Dicentrarchus labrax here in the UK, is that recruitment varies between successful year classes and less successful year classes – sometimes we have complete failures, due to the species being at the Northerly extreme of its range. During the past 30 years, commercial exploitation of the UK bass spawning biomass, has increased from a negligible level to a level which is altering the stock structure.
Whilst it is not essential for every fish to reproduce itself in order for the stock biomass to be ‘sustainable’ increasing exploitation is producing an imbalance in the UK bass stock structure, where larger, older fish are now rarer than was once the case. This of course, is of little importance to the commercial sector, nor to fisheries managers who aim to balance industry profit to MSYs.
Reducing numbers of larger fish is of direct importance to the recreational sector however, because the capture of larger fish is the aim of many anglers.
As you say – it is essential in such commercial fisheries that no growth overfishing occurs – if the resource is not to become endangered – however, the science, which is so vital in providing advanced warnings of potential problems in fisheries, tends to lag behind time by some years and then decisions to avoid any growth overfishing are both time consuming (often requiring negotiations between member states) and not implemented in time to be effective.
One only has to look at species which are subject to TACs to appreciate the downward spiral of spawning stock biomass following warnings from scientists, which are seldom headed, due to pressure from the dominant members of the EU who represent commercial fishing interests.
The closer one comes to exploiting any fishery at recruitment levels, the less time is available for avoiding action to be taken if things begin to go wrong. Even with species of early maturity and prodigious fecundity, such as cod, if the balance is overturned with insufficient warning time (or if warnings are continually ignored!!!) then recovery is likely to be long and slow and painful.
We also have a situation here in the UK where, after years of neglect from our Government, sea anglers are being given to opportunity to put forward ideas which will benefit their sport and the sportfishing industry, as well as species of fish which are of importance to us. This follows a number of Government-backed economic reviews of both the recreational and commercial fishing sectors.
It has been recognised by our Government that allowing some species of fish to grow to larger sizes will ensure that better value is derived from the natural resource and setting appropriate minimum landing sizes will also assist nature in replenishing itself, to compensate for the increasing extraction levels. One leading fisheries scientist has stated, “For some species and stocks we may need to think about moving in the direction of landing bigger fish, via higher MLSs and higher mesh sizes” and “The movement of fisheries management towards WSSD MSY targets implies a lower level of fishing effort in many fisheries. This will lead to larger stock sizes with a greater variety of age groups. Current levels of fishing mean that there are few larger fish and so a greater chance of taking small, unmarketable and juvenile fish. Fishing at moderate levels would mean that a greater proportion of the catch was likely to be above minimum sizes.”
What BASS is proposing in its Bass Management Plan is an alternative approach to managing a finite resource and one which promotes caution, to allow for the spawning variations, which bass here in the UK tend to experience.
Allowing more fish to breed will surely act as a buffer to sustain the spawning biomass through unforeseen recruitment failures.
To answer your final question, “Why the specialists in halieutic science do not definitively condemn this naive and fundamentally erroneous idea concerning the management of fishings? I would like to know…”
We doubt that many fisheries scientists would argue that providing an increase in spawning stock biomass is a bad (erroneous) management tactic, for the preservation of any species and the well-being of the people and economies relying upon them.
11 April 2007 – comment from Piscator (of Yorkshire):
Hippolyte (of France) would like to know why fisheries scientists do not condemn the idea that, to preserve a fishery resource, one needs a minimal size of capture that is at least equal to the size of sexual maturity of the species, so that all the fish have the possibility of reproducing at least once. The reason is simple. It is self evident that, if the relationship between “spawning stock biomass” and recruitment shows no evidence of “recruitment overfishing”, there is no need for additional protection of the spawning stock (since the stock and its fishery are sustainable), and management should focus on “yield per recruit” and avoiding “growth overfishing”, which depend on the size at first capture (not at sexual maturity) and exploitation levels. It all depends on what we know about the stock in question. Is there any real need to explain this further?