ICES CM 2015/A:01

Contribution to the ICES Annual Science Conference 2015 for the Theme Session 'Advancement of Stock Assessment Methods for Sustainable '

Escaping the Stranglehold by (Paciano, Umbria, Italy)1

Note. This is an update of a presentation to the ICES ASC (Bergen, , September 2012) entitled:

Some Good and Mostly Bad about Maximum Sustainable Yield as a Management Target

It is also an expansion of a Presentation in February 2015 to a special meeting of the Committee, on Fisheries of the European Parliament, on Maximum Sustainable Yield in .

In the process it has become a sort of manifesto.

1 [email protected] In a delightful parody of the notion of development a young, ‘activist’ distributed at a recent conference in Brussels, devoted to marine ecosystem conservation, a coffee mug bearing the slogan ‘To Maximum Sustainable Yield and Beyond’. It also carried a linear graph showing total fish rising to the sky!

An equivalent idea, posing as a campaign against is that we can control human caused global warming by all of us consuming even more energy so long as it is generated by solar capture, wind, tides, damming more rivers or by nuclear fission, instead of by drastically reducing the production of fossil fuels and not merely the consumption of them.

Even the application of an already agreed fisheries management policy, of keeping mortality rates less than what would produce ‘maximum sustainable yield’ seems now to be extremely difficult for the governing Council of Ministers the EU, if not impossible. This notwithstanding the undoubted economic and resource conservation benefits of such a policy.

At nearly 90 years of age I don’t have much personal interest left in saving the world. But I shall leave it with the firm belief that science, properly done and used, could do so. I am equally convinced that our political-economic system, based on property, hierarchy and greed, will not permit that. When the First World War had practically led to the destruction of industrial society the Russian Bolsheviks proposed an alternative. But Lenin and Trotsky were right, and Stalin wrong: the Revolution would fail if it did not become global. It did fail. Pope Francis seems to have similar ideas as expressed in his amazing recent encyclical Laudato Si.

Here, I try to take a rational view of possible futures for sea fishing as a worthwhile pursuit and important contributor to human food supplies. But I won’t bet on any of them happening.

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A Manifesto

What is Stock Assessment? When I decided to contribute to this Theme Session I thought to begin by defining ‘Fish Stock Assessment’. I had the cosy remembrance that it was a phrase used casually by a group of scientists in late 1949 at the Lowestoft Fisheries Laboratory in England – Michael Graham, its Director, , , and myself, with Basil Parrish, our colleague at the Marine Laboratory in Aberdeen, Scotland and E.S. Russell, Graham’s predecessor.

I found no documentary evidence for this, however. An Internet search for use of the term revealed about 50 major published references to it but with a great diversity of meanings and few attempts at definition. John A. Gulland, a next generation scientist at Lowestoft, popularized the phrase and his first book bore it as its title (Wiley, 1977) but with no definition. It appears again in Gulland’s next book (as Editor). ‘Fish Population Dynamics’ (Second Edition, Wiley 1998) as the title of the opening chapter by T. D. Smith: ‘Stock Assessment Methods: the First Fifty Years.’ In what I regard as the best general text on stock assessment and population dynamic – ‘Quantitative Fish Dynamics’ (Oxford U. P., 1999) T. J. Quinn II and R. B. Deriso frequently use the assessment term but in varying ways, and not defined. They do however provide a clear definition of ‘stock.’

The Aggregate of a Population that can be managed as a Discrete Unit.

Michael Graham recruited most of the new post- war staff at Lowestoft from among young scientists who had been engaged in operations (British term)/operational (US term) research, groups of mathematicians, physicists, biologists, chemists and others who had used scientific knowledge and method to 2 improve strategy and tactics of the Allied military. P. M. S. Blackett, one of the founders of this new discipline, defined it succinctly as ‘The analysis of data in order to give useful advice.’ Graham regarded the new as a peacetime application of their methods. ‘Assessment’ was a frequently used word in the literature of operational research: it seemed to be about the transition from data analysis to the offering of advice. So ‘stock assessment’ became a sort of applied population dynamics, analogous to

2 Mary Jo Nye ‘Blackett : Physics, War and Politics in the twentieth century Harvard U. P., 2004. See especially Chapter 3: Operational Research and ‘Atomic Weapons 1936-1962. 5 the well-known pairs ’pure and applied mathematics’, ’pure and applied physics’ etc. Indeed some of the interests of the stock assessment practitioners were close to the military activities, for example the theories of search for submarines and detection of enemy aircraft and laying of artillery were similar to the theory of efficient search for fish.

The application of stock assessment inevitably became closely associated with the problems of managing fishing in order to correct or avoid ‘over-fishing’ but there were evidently other possible applications including the productive development of new fisheries.

Here it seems pertinent to refer to one of Michael Graham’s much-quoted maxims. In his classic 1943 book (and, subsequently, in 1955, to a Conference of the United nations), The Fish Gate, Michael Graham expressed his Great Law of Fishing:

“Fisheries that are unlimited become inefficient and unprofitable”. I will add that this can happen also to badly managed fisheries, and those for which the market for their products expands geographically or by virtue of a change in their use, such as by shift from human food to fish-meal and oil.

Articles and books about stock assessment rarely contain clear, unambiguous definitions of ‘stock’ and, indeed, some usage is ambiguous, one being a ‘management stock’ which could be applied to all the fish in a politically designated ‘management area’ or region regardless of whether it contained a single self-contained biological population. Here I regard the term as generally applying to that part of a biologically self-contained population (of a species of fish or crustacean or mollusc) of interest to humans for exploitation now or in the future. The ‘part’ is usually defined by a lower body size –hence age – boundary, so that eggs and larvae are excluded. From that point of view the stock is an open biological system into which young animals are regularly recruited and from which there is continuous loss by death either ‘natural’ or by capture. If the stock is regarded as occupying a certain space, then it may be necessary to provide for consideration of gains and losses by immigration and emigration. Other inputs to and outputs from the open system, that are usually taken to be of second order interest, are nutrients and excreta.

Recruitment is commonly enumerated as the abundance of the youngest cohort in the exploited or exploitable population, the stock. However, for the management of fishing, by some methods –such as by setting maximum

7 catch limits, it is desirable to enumerate the pre- recruits, that is the cohort that will become recruits in the next recruitment period, usually a year.

Management policy At an early stage in its career, stock assessment was seduced by an evil vampire with the remarkable name Maximum Sustainable Yield – nicknamed ‘MSY. That was a political act arising from the negotiation of a peace treaty between the authorities of and the USA and most of the Allied Powers, (but excluding the USSR, the Peoples Republic of China and a few others) that came into force in 1952. The US had sought to impose on Japan an abstention principle that would prohibit a country’s fishers from operating in an area regarding the coastal state claimed to be already fully utilising the specified resources. Japan’s delegation wanted to know the meaning of full utilization to which the US response was ‘taking MSY’. This was the invention of a group of US biologists, led by Milner Schaefer, studying the sardine, halibut and yellowfin tuna fisheries of the US who had developed a stock assessment procedure that came to be called Surplus Production theory. MSY was defined as the peak of a parabolic or similar curve of sustainable catch against the biomass of the stock. Two other US biologists – William Herrington and Wilbur Chapman – active both in the political and commercial spheres, pursued, respectively, the ‘full utilisation’ and ‘abstention’ ideas vigorously for several years both in the Americas and in the UN System. But they did succeed in inserting it into a new International North Pacific Fisheries Convention involving the USA, Japan and Canada, but – interestingly - excluding the USSR.

The US tried, but failed, to get the abstention principle inserted in the text of the document coming from a Technical Conference on the Law of the Sea convened in Rome in 1955 at the HQ of the FAO of the UN. The US did, however, succeed in putting into the report the idea that MSY is one possible target for managing fishing. No more was heard about abstention in the UN context (partly because of an emerging consensus that the concept of the Territorial Sea could be extended from three or twelve nautical miles to up to 200 miles). Opponents of the MSY management imperative pointed out - correctly - that, apart from anything else, it would always automatically give an advantage to the strongest contestant in any dispute – particularly those who could make the best scientific case for claiming he was fully utilising the resource. Notwithstanding that concern, MSY was written into the convention on fisheries that emerged from the UN Conferences on the Law of the Sea,

9 held in Geneva in 1958 and 1959. That Convention never became operational because the Geneva conferences had failed to resolve the crucial and highly controversial matter of the breadth of the Territorial Sea. That and other matters were eventually settled in the comprehensive UN Convention on the Law of the Sea (UNCLOS) that came into force at the end of 1994, in which an 'Exclusive Economic Zone' (EEZ), having some of the features of a territorial Sea, was defined.

In a remarkable effort to provide a compromise the UNCLOS awards the coastal state the sovereign right ‘to maintain or restore populations of harvested species in its EEZ at levels which can produce the maximum sustainable yield, as qualified by relevant environmental and economic factors.’ However, although the coastal state must determine its capacity to harvest the living resources of the EEZ, where it does not have the capacity to harvest the entire allowable catch (as determined by the MSY criterion) or, presumably, the wish to do so, or must give other States access to the surplus of the allowable catch, presumably taking into account the coastal state’s decision as to what exactly constitute relevant environmental and economic factors.

(This history is fully documented and analysed in a book, ‘All the Fish in the Sea: ‘Maximum Sustainable Yield and the Failure of Fisheries Management’, by the American historian Carmel Finlay (U. Chicago Press, 2011)’

Relaxing the Conditions of the Target. The UNCLOS enshrines MSY as a principle objective of managing fisheries for sustainable catches, but with a very important condition: ’as qualified by relevant environmental and economic factors’. This offers us a way of escape from the stranglehold of managing fishing in order to maximize physical yield. There may or not be environmental or, indeed, social reasons for substantial departure from the MSY objective but there are certainly always good economic reasons for doing that, principally because the costs involved in taking a high sustainable catch are at least as important as the size and market value of the catch. The European Commission has recognized that, by taking the advice of the European Parliament to make the basic management objective to fish with intensity less than would be required to take MSY. How much less is not yet decided but that decision will have to take into account both economic and social aims and must be made in accord with the best scientific advice.

11 Discussion of ‘how much less’ has until now focused on a target fishing mortality rate, F, as a percentage of F-MSY or, alternatively, as a target SY that is some predetermined percentage of MSY. I prefer, here, to refer to the former simply because next year’s SY always depends critically on the next incoming recruitment, which can be guessed but is never known and can be extremely variable.

It is unfortunate to find oneself depending on the old, discarded target to define the new one. There are, of course other maxima in fish stock assessments, one being the maximum sustainable economic yield (MSEY), the maximum difference between the market value of the catch and the cost of taking it, discussed by several scientists and economists, beginning more than 60 years ago. One could define an F- target somewhere between F-MSEY and F-MSY (remembering that F-MSEY is always less that F- MSY and can be much less)as a specified multiple of F-MSEY lying within that range. But I think our problem goes deeper than that. Why define a social and economic target simply as a quantity, by weight or gross or net value?

F-MSEY and MSEY can be easily, though approximately, estimated if the break-even catch-rate is known, from simple economic information – that is the catch-rate the cost of obtaining which is equal to the value of the catch.

There are, naturally, several social reasons why it might be desirable to manage so that the fishing mortality/effort more than that needed to secure MSEY: maintaining employment, meeting a nation’s need for a reserve of experienced seamen, maintain ship-building and repair capacity and so on.

A Little History and Michael Graham both published, in the 1930s, curves of sustainable catch against fishing rate, with peaks they called ‘optima’, but neither of them suggested that these should be regarded as management targets. In fact their curves were very different from each other. Hjort’s was the catch in numbers, of fin whales, based on mortality and calf birth rates. Graham’s was for catch in weight of an unspecified fish, based on mortality and body growth rates†. (Holt, S. J. 214 ‘The Graceful Sigmoid’ ICES J. Mar. Sci, 71(8): 2008-2011.

Not Peaks but Slopes We are so habituated to thinking in terms of maxima that it is hard to think outside that box. But things perhaps get easier if we think about

13 rates and slopes rather than quantities. Whether or not they have maxima (depending on the selectivity of the fishery) curves of sustainable yield-per-recruit against always have a gentle slope immediately to the left of the peak or asymptote. This means that the catch rate (Y/F) in that region is much higher than that associated with the peak, while the catch itself is only slightly less than the peak catch. This has enormous economic implications, especially as there is no guarantee that a at the maximum will be profitable.

The slope of a curve of sustainable yield (by weight or value) is determined by the interaction of a natural mortality rate by which fish die at a relatively unvarying percentage (logarithmic) rate throughout their lives after recruitment, and the curve of increase in individual body weight, which continues throughout their lives. This latter curve always has a high specific growth rate when the fish is young and small. As it grows the absolute rate of growth reaches a maximum, visible as an inflexion in the growth curve. The inflexion is commonly close to or somewhat lower or higher than the median size at which the fish attains sexual maturity and begins to breed. After that growth continues but at an ever-decreasing absolute rate, so that body weight approaches an upper asymptote.

Cohorts The interaction between two rates of change – growth and death, results in the total weight of a cohort (all the fish born in the same spawning period) increasing, reaching to a maximum when the weight of the fish in the cohort reaches a certain critical size at a critical age, these depending only on the value of the ratio MK/ (natural mortality rate to the driving parameter of the von Bertalanffy growth function) for that species- stock. I think it was William Herrington who first pointed this out in the 1930's and to observe that a maximum catch could be obtained by refraining from fishing until the fish in the oldest cohort had reached critical size and then catching all of the survivors in that cohort. This practice would likely be theoretically sustainable because critical size must always be bigger than the size at the inflexion of the growth curve and will usually be bigger that the size at maturity.

It is worth considering the implications for conclusions about critical ages and sizes, particularly of possible variation in rate of mortality with age, and changes over time in the values of either or both parameters of the body growth function. These will generally affect conclusions quantitatively but not much in general terms.

15 Of course such an MSY is not in practice attainable because we do not have the technical means of catching all the surviving fish at one time in one cohort, and leaving the other younger cohorts alone. But the efficiency of any particular selective but eumetric fishing for a local msy can be indexed by its ratio to the theoretical MSY.

A fishery at or near msy local level causes a substantial reduction in the biomass of the stock from its level in the unexploited (‘virgin’) state and, depending on the selectivity, this may cause the average recruitment to decrease to somewhat less than that experienced in the virgin or lightly exploited stock. The effect of this is to reduce further the slope of the curve of yield against fishing mortality rate in the vicinity of the peak, and hence enhance the economic advantage of managing the fishery to hold the fishing mortality rate to a level substantially less than that which would provide msy. However, because catch and effort change in he same direction the change in cpue- hence profitability - will be small.

A problem in discussing this further is that the highest SY obtainable from a stock depends critically on the selectivity by which it is exploited. With low selectivity (fish beginning to be caught when they are quite young and small) the peak of the SY curve, what I have called the local msy, occurs at a relatively low fishing mortality rate, and the local msy is relatively small in weight. If selectivity is high – fish perhaps not beginning to be caught before reaching sexual maturity – then the local msy will be higher but obtained only by exerting a substantially higher fishing effort, and therefore with diminished catch rate. The actual scale of these quantities - sustainable catches and fishing mortality rates - is determined by the value of the ratio M/K (natural mortality rate to the driving parameter of the expression for growth in individual weight for the particular stock)

More about Selectivity. Published advice about MSY or some other reference point related to it, often contains no reference to the selectivity of the fishery being assessed. This is so, for example of much of the advice offered to the EU Commission by ICES. Advice of this kind, if based on age-structured assessments is useless or misleading. A minimal requirement is that the assessment model applied to a fishery employing towed nets such as trawls and seines should incorporate a function specifying the sigmoid curve of selection against body size or age – perhaps approximated by a knife-edge – or the corresponding bell-curve for

17 hooks and line, and gill nets, perhaps approximated by two parallel knife-edges. (Of course, if the advice comes from a Surplus Production Model then it cannot carry any such indication because such models assume that age and body size play no part in determining the productivity of the stock.)

There appears to be a common assumption that the selectivity of the fishery cannot be affected by the management regime, and that selectivity is determined entirely by fixed sizes of meshes and hooks. This is both wrong and a dangerous assumption. While a managed change in the fishing mortality rate might not in itself cause a change in selectivity, there are several situations in which it can do so. One is in a mixed fishery. If management of two or more of the species affects the relative abundances of the species then, since virtually all species are partially geographically segregated, the abundance changes will lead fishers to adapt their operations, usually by a geographic or seasonal shift. Similar changes in selectivity can arise, for the same reasons, if a Marine Protected Area (MPA) that prohibits fishing is declared; Parts of inhabiting MPAs practically always have age/size, sex or reproductive states somewhat different from those of the overall stock composition, and so the selectivity of the newly geographically restricted fishery will change. Assessments offering management advice should therefore always refer to the original selectivity, whatever that might be, and also suggest what changes might occur under the new regime.

Minimal Economics If a management target other than some maximum is to be chosen, it seems to me to imply that ‘stock assessment’ has to include at least some economic data and calculations, at least concerning the costs of fishing, the market values of fishes and, especially, information indicating what would be the threshold catch rate to be ensured in order to avoid multiple bankruptcies of fishing operations. And in those circumstances it surely becomes necessary to review the basic method of management to maintain the desired fishing intensity.

Historically the advice of scientists has been to manage primarily by regulating the fishing power of the fleet or fleets. However, since the end of WWII, it has proven difficult to do that, for political and even constitutional reasons. Therefore, instead of regulating the input to the fishing system it has become almost universal practice to place restrictions only on the output, in a variety of ways. One of the first used, in the international management of the halibut fishery in the eastern North Pacific, was to limit the duration of the legal fishing season, setting

19 opening and closing dates. Elsewhere, and later, and now practically worldwide, extremely complex efforts are made to regulate the output by setting catch limits – Total Allowable Catches (TACs) in the current jargon. This has led to many difficult problems. Among them are the following:

1. Estimating the desirable catch calls for knowledge of the very variable, essentially unpredictable, recruitment in the coming year. 2. Since fishing incorporates a random process it is impossible to avoid unintended excess catch – and also unintended catches of non-target species. This can be partially corrected by annual adjustments to TACs but this means that the fishing is caused to be less stable than it needs to be. Similar considerations apply to the – usually lesser - consequences of imposing other limitations on landed catches, such as setting minimum legal length limits. And the methods to regulate output become even more intractable in mixed fisheries – that is in which several target species are caught simultaneously in the same operations.

Attempting to ensure rational fishing by controlling outputs is equivalent to driving a vehicle using only the brakes instead of adjusting both the brakes and the throttle.

Imposed Inefficiency In his evidence to a special meeting of the Atlantic Marine Fisheries Commission of the USA, in Baltimore, Maryland in 1942, the fisheries scientist R. A. Nesbit well described these kinds of regulatory measures as imposed inefficiency. He said to the Commissioners:

“I earnestly recommend that the Commission adopt a policy and program that will protect the fishermen as well as the fish. In one important respect such a program will be easier to develop than a conventional program based on a policy of imposed inefficiency.”

Rational, Irrational and Eumetric Fishing Then, a year later, a Canadian biologist, A. G. Huntsman, wrote in Science 'irrational fishing is where the take in proportion to the effort fails to yield a satisfactory living to the ’, so bringing economics into the discussion. Eventually, in 1949 Huntsman told the United Nations Scientific Conference on Conservation and Utilization of Natural Resources (UNSCUR), held that September at Lake Success, NY, that

“The take should be increased only as long as the extra cost is offset by the added revenue from sales”.

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Huntsman’s formulation points us to a way to identify a useful reference point on the curves of catch value against cost related to fishing intensity.

Incidentally, the concept of ‘rational fishing’, much loved by Hjort, Russell and Graham, as well as by Beverton and myself, appeared in fisheries literature earlier than usually thought. In his chapter for Gulland’s 'Fish Population Dynamics', Tim Smith drew attention to the wise words of a German scientist, H. M. Kyle, published in 1905; ‘Statistics of the North Sea fisheries. II Summary of the available fishery statistics and their value for the solution of the problems of ’. Rapp. Cons. Explor. Mer 3. 58p. For Kyle ‘rational fishing is not subject to natural laws but, rather depends on the monetary side of the matter, the expenditure on boats and gear on the one hand and the gross and net income on the other.’

In 1957 Beverton and myself added to this the idea of eumetric fishing in which selectivity and fishing effort are optimally balanced. The need for such an approach in practice became evident during a workshop convened by the ICNAF in and led by Beverton and I. The purpose of the workshop was to evaluate proposals to increase cod-end mesh sizes to be used by US and Canadian vessels for haddock on George’s Bank. We found that the proposed increase in mesh size would result in an increased catch, and catch rate if the fishing intensity remained unchanged. However, we advised the Commission that, as fishing effort would not be regulated by ICNAF, this meant that George’s Bank haddock fishing would become more attractive economically, leading to an increase in the fishing mortality rate, which would negate the gains expected from the mesh size increase.

The fact is that consequences of this kind, having knock-on effects throughout the fishing system have never been recognised and accounted for by regulatory authorities. increase.3

Sub-Optimal Fishing and Sustainability

3 For further analysis of these issues see my 2013 paper: ‘The Evolution of the Objectives, Science and Procedures of Fisheries Management since 1945’ In ‘Fisheries management in a Historical Perspective’, Eds. Ingo Heidbrink and Matthew McCarthy, Studia Atlantica 12. North Atlantic Fisheries History Association, Hull, UK. This is the Report of the 12th North Atlantic Fisheries History Conference, held at Old Dominion University in in Norfolk, Virginia, August 2009. 23 A balance of intensity and selectivity of fishing (that is selectivity providing maximum catch for a given intensity, or an intensity giving maximum catch for a given selectivity) is not necessarily optimal or even desirable. In early experiments with bottom trawls it was found that increasing cod-end mesh size could increase the efficiency of the gear, presumably by allowing less towing power to conduct effective hauls. And of course in mixed fisheries it is not possible to optimise mesh size for two or more species, and one might have to consider optimising for the most valuable species)..

Already, at the 1955 UN Conference, Michael Graham had said – especially to the US delegation that was pushing hard for an MSY imperative - that ‘our objective (he was speaking for Western European attitudes) ‘is not to seek maxima but, rather conservation measures ‘to make things better’. Without using the word they were advocating sustainability, which became a global buzzword soon after Gro Harlem Brundland introduced us all to her quasi-oxymoronic Sustainable Development.

The closest look by scientists at the sustainability concept has, I think, been made by the Development Group of its Scientific Committee set up by the International Whaling Commission (IWC) in the 1980s to devise a Revised management Procedure (RMP) for managing commercial whaling. To begin with, the idea of ‘a procedure’ was taken literally in a fisheries context for the first time, mimicking its use in medical practice, particularly surgery: following in sequence a fixed set of pre-defined actions, equivalent to an algebraic algorithm. The procedure has to be tested by simulating application, using an appropriate stochastic stock dynamics model. To do that a finite ‘management period’ must be selected and the effectiveness of the procedure judged from the cumulative catch during the period and the state of the stock at the end of the chosen management period. This also involves setting multiple criteria, such as avoiding unintended depletion of the stock to below some critical level, expressing all such events in terms of pre-defined probabilities.

In the IWC managers had also determined that the system should be as stable as practicable, not permitting frequent or substantial changes in regulation, except in case of perceived emergency. This is a far cry from the popular myth that sustainability is – like Shirley Bassey’s and Ian Flemings’ – 'diamonds are forever', provided ‘the environment’ does not change.

The key to the IWC success in this endeavour was the decision by the Development Group to go far 25 beyond developing a population model, and to simulate the entire management process. The credit for this must go to three brilliant members of the Group – Justin Cooke, William de la Mare. Douglas Butterworth and its Convenor, Geoffrey Kirkwood, providing a combination of talents in mathematics, statistics, biology and engineering, from three Continents. This little collection mimicked the structure and working methods of the best wartime operations research teams that had moulded Graham’s vision of the future of fisheries research.

Dynamics of Transition Included in my understanding of 'stock assessment' is consideration of options for effecting a transition from a stock that is in a state that is not optimal, and probably not ‘steady’, to the chosen optimally managed state providing high and relatively stable catches. The main consideration is the speed at which the desired transition is to be accomplished and one measure of performance could be the cumulative catch during the transition period. The speed is, of course determined by the pattern of fishing intensity exercised during the transition as well as by the biologically determined dynamics of the stock. Managers might wish to make the transition with minimum delay but that could have unforeseen social and economic consequences. Scientific advice based on the population dynamic model plays an important role here.

Monitoring Monitoring whether the fishery is performing as predicted is evidently an important way of testing the assessment procedures under management but it is an assessment activity to which far too little attention has been given in practice. Design of a monitoring system must include all such matters as: - examining whether the population model used to make the assessment is structurally appropriate: - determining whether the estimates of values of the parameters in the model are correct: - checking that the agreed management measures are all being taken in a timely manner, and being effectively enforced: - checking the routine procedures for recording catches and their compositions, including unintended catches; - checking the validity of assumptions concerning selectivity.

Additionally, the monitoring system must include rules by which regulations are to be changed if significant departures from the intended or expected situation are discovered.

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Acknowlegements

I have discussed the opinions I have expressed in this manifesto during the year with several other scientists but especially with Michael Earle, Adviser to the Green Alliance Group in the European Parliament I am particularly grateful to Dr for his many suggestions for improving an earlier version, practically all of which I have included in this revised version. Thanks also to my son Tim for his relentless editing.