Publication - Research publication

Management Of The Scottish Inshore Fisheries; Assessing The Options For Change

Published: 7 Jan 2015
Part of:
Marine and fisheries

An analysis of the impacts from different options for the management of the Scottish Inshore fisheries. In particular, the report provides an appraisal of scenarios related to restrictions on the use of mobile fishing gears within one and three nautical m

375 page PDF

8.9 MB

375 page PDF

8.9 MB

Management Of The Scottish Inshore Fisheries; Assessing The Options For Change

375 page PDF

8.9 MB


In managing inshore fisheries for the benefit of society as a whole it is necessary to embrace the interests of all stakeholders. It is well established that a proportion of the human population has an altruistic concern for the natural world which is independent of their use of it. This is usually known as the Existence Value.

Whilst the general public are not indifferent about the quality of marine environment, their preferences cannot be expressed in the market place, and unless government intervenes they will be ignored in resource allocation decisions. In other words there are missing markets which result in sub-optimal outcomes.

Because there is no actual expenditure involved there is no economic impact dimension to measure. All that can be measured is the change in human welfare. A measure of how worse off an individual might be is the amount they are willing to sacrifice (i.e. WTP) in order to protect or improve the marine environment. The relevance of monetised non-user values for public sector decision making is now widely accepted and is incorporated in the form of guidance in the Treasury Green Book and other Government assessment documentation.

Conceivably, even those engaged in RSA and RD could perceive a reduction in their well being from simply knowing that marine biodiversity has been decreasing. For this to be a genuine Existence Value, this reduction would have to be completely separate from the impact of environmental change on their fishing or diving operating largely through changes in fish stock abundance.

Whilst at a theoretical level we can distinguish between use and non use values, in applied work it is extremely difficult to separate these. This might particularly be the case for a country such as Scotland where a large proportion of the population live close to the sea and may engage in more informal passive use of the marine environment. In applied work, very detailed sampling would be required to avoid the capturing the more passive use values. Given this we prefer to term assessment of the values held by the general public as General Public Non User Value ( GPNUV).

The complete exclusion of these values in the context of this study would be controversial and would undermine the credibility of the work and decisions that it might inform. The relevant question is therefore how they should be incorporated. In an ideal world, primary research would be undertaken. Because of resource constraints, it is necessary to use benefit transfer.

20.1 Benefit Transfer

McVittie and Moran (2010) is the only relevant study. They undertook a stated preference choice experiment to estimate the non-user benefits derived by UK residents from implementation of the proposed MCZs and MPAs.

For Scotland, Wales and Northern Ireland, approximately 150 respondents each were sampled (75% coastal, 25% non-coastal).They were presented with a choice experiment involving policy outcomes, which are spatially remote from respondents who were thus probably non-users for the broadly defined policy outcomes.

It should be noted that about 3% of the UK population is a diver, a sea angler or both. The sample might therefore have picked up users who, because they interact directly with near shore fish stocks (i.e. RSA and RD). They might declare a WTP which incorporates both their direct use (of near shore fish stocks) and non-use values related to their broader altruistic concerns for the marine environment. If this occurred, then mean WTP willingness to pay (ie GPNUV) will be inflated. This study will therefore have double counted RSA and RD user values. Given the 3% participation rate double counting of their user value is probably not an issue.

The sample might also have picked up users who interact indirectly with near shore fish stocks, (Other Marine Recreational Activity ( OMRA)). They might declare a willingness to pay that incorporates their indirect use of near shore fish stocks as well as their non-user values. With 75% of respondents from coastal locations, McVittie and Moran (2010) might have picked up some OMRA user value. This is not a problem because we are unable to estimate any of the OMRA user value.

The prices in the table below represent mean willingness to pay in £ per household per annum. Respondents were presented with two baseline policy attributes. One expressed in biodiversity terms the other in terms of environmental benefits flow. They were also presented with an increase in each of the two baseline attributes. Both of the increased levels were valued relative to the baseline (continued loss of biodiversity or environmental benefits). The difference between the two can also be calculated by subtracting the value of one from the value of the other.

Table 20.1.1 Mean WTP Individual Country Samples (£/household/annum).

Policy Outcome England Scotland Wales Northern Ireland
Halt loss of biodiversity £69.49 £20.92 £107.39 £33.90
Increase biodiversity £69.16 £23.76 £61.04 £38.22
Halt loss of environmental benefits £30.79 £16.16 £139.08 £18.35
Increase environmental benefits £34.27 £19.45 £158.53 £30.65

As an example, in the Scottish sample, the mean implicit price for "halt loss of marine biodiversity" (for the UK wide network of MCZ's) is £20.92 per household per annum, but this only increase by £2.84 to £23.76 for an increase in biodiversity.

From the table above, there are significant differences between countries, with Scottish households WTP much less to stop the continued decline.

There would also appear to be indifference between degrees of improvement. McVittie and Moran point out that for many individuals the loss of something has a bigger negative impact than the positive impact from an equivalent gain, but that scope insensitivity may also apply.

Table 20.1.2 Aggregate Annual Non-Market Benefits for Policy Attribute Levels (£M)

England Scotland Wales Northern Ireland Total
Number of households (M) 21.73 2.31 1.24 0.67 25.95
Halt loss of biodiversity £1,510. £48.30 £133.20 £22.70 £1,714.
Increase biodiversity £1,502. £54.90 £75.70 £25.60 £1,658.
Halt loss of environmental benefits £669. £37.30 £172.50 £12.30 £891
Increase environmental benefits £744. £44.90 £196.60 £20.50 £1,006

The work of McVittie and Moran has demonstrated that the Scottish general public would benefit if biodiversity loss was halted and biodiversity increased. These benefits are captured in the amount they are collectively willing to pay to achieve these outcomes.

There are a number of difficulties in using the above results for benefit transfer. Firstly, with respect to aggregate values, the WTP is by Scottish residents for UK wide preservation or improvement. Scottish WTP for Scottish improvement should be less, though the scope insensitivity noted by McVittie and Moran and Kenter et al suggests that might not be too much of a problem. On balance, uncritical benefit transfer will certainly raise the possibility of overestimation of the benefits from the 0-1 NM or 0-3 NM restrictions.

Second, the purpose of the MPZ / MPA networks is quite different from the 0-1 NM and 0-3 NM being considered by this study [59] . The 0-1 NM and 0-3 NM restrictions are essentially based on the functional significance of the near shore. The decision to assess these particular options may be based in part on a suspicion that the increased use of mobile demersal gear in near shore, particularly in nursery areas, might be responsible for the observed reductions in geodiversity, biodiversity, and the biomass of benthos species and other stocks including some other shellfish and demersal species. If mobile gear is having these impacts, and in the threat is ongoing, the general public would be willing to pay for ecosystem protection and eventual recovery. Although the 0-1 NM and 0-3 NM restrictions are not aimed at protecting and enhancing biodiversity and geodiversity for their own sake, they could deliver these outcomes. It is being argued that in the minds of the general public the near shore restrictions would have an impact, in terms of preservation and enhancement which would be much greater that the impact of the MPAs (see Section 3.5.1).

Third, there is the question of whether to focus on biodiversity or the flow of environmental benefits. The former is preferred since it is more consistent with genuine GPNUV, rather than the user values or user option value implicit in benefit flows.

The greater error would be to completely exclude non-user values. On that basis, this study assumes that the orders of magnitude revealed by McVittie and Moran are probably relevant. Unfortunately, there is no basis on which they can easily be finessed to better transfer them. In any event, finessing, which would probably have to assume underlying relationships, could not embrace the apparent scope insensitivity.

Given these considerations it is assumed that the Scottish non-user value is around £48m per annum and that increased biodiversity will increase values by £6.6m per annum. These are used to provide an illustrative estimate of the magnitude of general public values for Scotland and for the IFG areas.

Finally, it should be appreciated that the very high estimate (£48m) is only relevant when the status quo scenario is "continued decline to zero."

20.2 General Public Non-User Value for Scotland

The status quo scenarios of continued decline and stability are retained. Given the scope insensitivity, there is no adjustment of £6.6m improvement element. It is however recognised that there is an argument to suggest that WTP to pay for a biodiversity improvement should vary with the magnitude of the improvement. One problem is deciding on whether the £6.6m represents the Major Transformative Effect and the other two scenarios are fraction of this. Alternatively, the £6.6m could be the Minimal Enhancement. Given this anchoring problem, as well as the other benefit transfer difficulties it was felt that, on balance, variations in the general public's WTP would introduce an element of spurious accuracy.

Table 20.2 General Public Potential Net Economic Values (Scotland Scenarios)

Impact Scenarios: / Status Quo Scenarios: Major Transformative Effect Some Enhanced Flow Minimal Enhanced Flow
Continued Decline to zero £54.6m £54.6m £54.6m
Stability £6.6m £6.6m £6.6m

20.3 General Public Non-User Value for IFG Areas

The allocation of the Scottish values needs to be apportioned according to population size. It has been necessary to identify the population size of IFG areas. This was done by allocating data zones to the nearest IFG and then summing.

Table 20.3 IFG Populations

IFG Population %
South West 2,258,654 44.6%
North West 40,850 0.8%
Hebrides 26,450 0.5%
MF& NC 297,853 5.9%
Orkney 19,220 0.4%
East 2,399,213 47.4%
Shetland 21,960 0.4%
Total 5,064,200.00 100.0%

The relative population sizes were used to allocate the Scottish general public values across the IFGs

Table 20.4 General Public Potential Net Economic Values IFGs

IFG Impact Scenarios: / Status Quo Scenarios: Major Transformative Effect (£'000s) Some Enhanced Flow (£'000s) Minimal Enhanced (£'000s)
South West Continued Decline to zero £24,352 £24,352 £24,352
Stability £2,944 £2,944 £2,944
North West Continued Decline to zero £440 £440 £440
Stability £53 £53 £53
Outer Hebrides Continued Decline to zero £285 £285 £285
Stability £34 £34 £34
MFNC Continued Decline to zero £3,211 £3,211 £3,211
Stability £388 £388 £388
Orkney Continued Decline to zero £207 £207 £207
Stability £25 £25 £25
East Coast Continued Decline to zero £25,867 £25,867 £25,867
Stability £3,127 £3,127 £3,127
Shetland Continued Decline to zero £237 £237 £237
Stability £29 £29 £29