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What issues can biologists and economists (better) address in

common?

Presentation at the FAME workshop 6th-8th June 2007

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• Background– We always hear that a multidisciplinary approach is needed to analyze

problems in fisheries.– This of cause involves researchers with different backgrounds and

training.– But just a little thinking suggest that not every (single) research question

requires input from several research disciplines.– So, which questions do social scientists (read economists) take care of

and which do natural scientists (read ecologists/biologists) take care of?– And which questions do we handle in common?– My thoughts are based both on some thinking and some real experiences

obtained in several projects.

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• What are typical (research) questions to be asked?– How big is the stock size?

– What does the costs look like? Ex-vessel prices?

– Is there fleet overcapacity? Buybacks?

– Biological or/and technical multispecies issues?

– Spatial and seasonal aspects of the exploitation?

– How do we achieve as much rent as possible from the fishery? (management and allocation issue)

– Minimizing the negative effects of fishing on the eco-systems.

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• Greenland Shrimp Fishery 1989-1991– License system under TAC. More and more licenses was issued =>

resulting in bad vessel economy and wrong product mix. This was very serious for the Greenlandic economy as a whole.

– Commission (with me as the secretary - doing all the work!) with vessel-owners and civil servants reported that the current fleet structure was producing the wrong mix (loss in value added) and that there was too many licenses (vessels) issued.

– This lead to ITQs implemented in 1990/91 and this system is still functioning.

– Today 12 vessels, in 1989 around 55 vessels.– This was done without any biologists involved. And with the task

given it was – after my opinion – also right. Because it was an efficient (max rent) problem and allocation problem.

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1920 1940 1960 1980 2000 2020 2040 2060

Year

0

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Cat

ch o

f shr

imp

('000

tons

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Moderate scenario

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500

1920 1940 1960 1980 2000 2020 2040 2060

Year

Cat

ch o

f cod

('0

00 to

ns)

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Cat

ch o

f shr

imp

('000

tons

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Optimistic scenario

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1920 1940 1960 1980 2000 2020 2040

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ch o

f cod

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Cod

Shrimp

Pessimistic scenario

From the ACIA report 2004

(www.acia.uaf.edu)

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Available projections suggest that climate change over the next 100 years is very likely to benefit the most valuable fish stocks at Greenland. This is particularly likely to be the case for the cod stock, which could experience a revival from its current extremely depressed state to a level, where it could yield up to 300000 t on a sustainable basis. However, climate change and increased predation by cod could lead to a dramatic fall in the sustainable harvest of shrimp by up to 70000 t. The value of the increased cod harvest would, however, greatly exceed losses due to a possibly reduced harvest of shrimp. In fact, this change could lead to doubling or even tripling of the total production value of the Greenland fishing industry. Thus, the projected climate change could have a major positive impact on the Greenland fishing industry. However, this is highly uncertain.

Conclusions

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Economic effects

• The economic and social impacts of changes in fish stock availability depend on the direction, magnitude, and rapidity of these changes. The economic and social impacts also depend, possibly even more so, on the ability of the relevant social structures to adapt to altered conditions. Good social structures facilitate fast adjustments to new conditions and thus mitigate negative impacts. Weak or inappropriate social structures exhibit sluggish and possibly inappropriate responses and thus may exacerbate problems resulting from adverse environmental changes.

• One of the most crucial social structures in this respect is the fisheries management system. This determines the extent to which the fisheries can adapt in an optimal manner to new conditions.

• This study needed both biologists and economists. The study was of the ”if … what…?” I think that the scenario work is an area where both disciplines can come into play. Again, the research question has to be formulated at the outset.

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• Gordon-Schafer model to illustrate the division of work within a common framework.

• Biologists are finding the growth function

• ? is finding the production function (Y=qES)

• Cost function is economists work

• So, again if the research question is relevant to handle with a Gordon-Schafer model then the division of work is more or less obvious.

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Figure 2. Denmark: Stock relative to optimal steady state

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optimal s.s.

moratorium

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Figure 5. Denmark: Growth function and actual and optimal harvest against stock

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Stock (1000 tons)

Yie

ld (

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Grow th

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Cod biomass relative to the optimal

Common data period1964 - 2000

Period with TAC-regulation1978 - 2000

Denmark 0.57 0.49

Iceland 0.68 0.60

Norway 0.77 0.61

Efficiency of the cod harvesting policies

Common data period1964 - 2000

Period with TAC-regulation1978 - 2000

Denmark 2.60 2.96

Iceland 3.71 5.74

Norway 2.73 4.13

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• However, no biologists were involved. In fact, there could have been, because estimating growth functions are not trivial.

• But, I think the research question determined the choice of model approach. It is an aggregated empirical model which can show trends and structure of the underlining system. Detailed yearly quota setting is not possible.

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• Overall a choice between fish and economic activity:• P = s(X)• Y = d(P)• W = w(X,Y)P is pollution, X is goods, Y is tons of fish. s is thepollution function, d is the dose-response function andw is the welfare function.Biologists and others comes with the Transformationfunction and social scientist comes with the Welfarefunction?

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• A current project: IMPSEL.• It is a study of changing the selectivity of the gear, so discards

and bycatches are reduced.• However, we agreed from the beginning that the framework

was economic evaluation (CBA-type) including a ”private CBA”. And effects not possible to put money values on had to be described.

• There has been a division of work (however, not always 100% clear).

• We have managed to stay on track, but as I see only because we beforehand agreed on the modeling framework. But there has been problems with how the interfaces should be handled.

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• Conclusions– Be very careful to formulate your research

questions.– Decide on the modeling framework and be careful

about the interfaces between disciplines.– Do these two things when the project application is

formulated.– Scenario modeling seems to be an area where

biologists and economists can work together. – Respect others work, but question it!