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Operational tools and adaptive management

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3.4.1 The s<strong>and</strong>eel fishery in the North Sea<br />

S<strong>and</strong>eel in the North Sea is considered to consist of several geographically distributed substocks.<br />

As the fisheries off the Scottish <strong>and</strong> English coast has been more or less closed in<br />

recent years we have concentrated on the Danish <strong>and</strong> Norwegian s<strong>and</strong>eel fisheries in the<br />

North Sea.<br />

The s<strong>and</strong>eel fishery is an industrial fishery. As can be seen from Table 3.10 both spawning<br />

stock biomass (SSB) <strong>and</strong> catches have fluctuated significantly during the last decade. This is<br />

also the case for the catch per unit effort (CPUE), measured as kg catch per kWday (the<br />

CPUE numbers in the table are not corrected for technological progress). Technological<br />

progress <strong>and</strong> reorganisations in the fishery have reduced the input in the form of kW days, <strong>and</strong><br />

the table shows that since 2003 there has been a significant increase in the CPUE.<br />

Table 3.10 SSB <strong>and</strong> Catches in 1000 tonnes, <strong>and</strong> CPUE in the Danish <strong>and</strong> Norwegian<br />

s<strong>and</strong>eel fishery in the North Sea<br />

SSB, 1000<br />

tonnes<br />

Catches in 1000<br />

tonnes<br />

CPUE (kg<br />

catch per<br />

kWday)*<br />

2000 670 71,6151303<br />

2001 834 69,0366667<br />

2002 350 808 89,8080192<br />

2003 420 304 40,1594653<br />

2004 200 336 42,7267819<br />

2005 190 170 46,860338<br />

2006 190 258 65,7373461<br />

2007 350 196 71,8381593<br />

2008 600 335 89,1620936<br />

Source: ICES, database <strong>and</strong> Advice 2008, Book 6<br />

* this is based on data from Denmark only<br />

S<strong>and</strong>eel is important as food for predators such as fish, marine mammals <strong>and</strong> seabirds. The<br />

<strong>management</strong> objective should ensure that the stock remains high enough to provide food for<br />

predator species <strong>and</strong> prevent depletion of local aggregations, particularly in areas of predator<br />

concentration. Due to the important role of s<strong>and</strong>eel as prey for sea birds, we now assume that<br />

a bird watchers‟ organisation (henceforth called NGO) obtain a say in the <strong>management</strong> of<br />

s<strong>and</strong>eel <strong>and</strong> thus can suggest an incentive scheme similar to that of the authorities to be used<br />

to regulate the effort used in the fishery, <strong>and</strong> thus the harvest. We assume that the NGO only<br />

holds environmental interests towards the s<strong>and</strong>eel fishery. Using the common agency model<br />

presented above <strong>and</strong> in annex 3 the results of an additional stakeholder in the <strong>management</strong> of<br />

the s<strong>and</strong>eel fishery is given below:<br />

Let the incentive scheme of the NGO be given by 0 E j , whereas t 0 tE j is the incentive<br />

scheme of the authorities. Further, let w denote the optimal tax/subsidy rate when the<br />

authorities manage the s<strong>and</strong>eel fishery alone. Then, when both the NGO <strong>and</strong> the authorities<br />

have a say in the <strong>management</strong> of the s<strong>and</strong>eel fishery, the tax/subsidy rates relates to w as<br />

shown in table 3.11.<br />

Table 3.11 Optimal tax/subsidy rates when there are two principals to have a say in the<br />

<strong>management</strong> of the s<strong>and</strong>eel fishery relative to when the fishery is managed by<br />

the authorities alone<br />

Variable t* τ* t*+τ*<br />

Relationship t* 0 t*+τ* >w*<br />

35

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