Nephrops fleet - optimisation modelling: policy brief

Economic research providing a valuable addition to the evidence base of Scotland’s Nephrops fishery to help inform discussions on the future of fisheries management.

 Key Findings

The research shows that in 2017 employment on Nephrops creel vessels in the West of Scotland was around 210 on a full time equivalent basis, generating gross value added of around £5 million and landing 1,300 tonnes of Nephrops. Employment was around 510, on a full time equivalent basis, on-board trawl vessels in the West of Scotland, generating gross value added of around £12 million and landing 8,500 tonnes of Nephrops. In the North Sea, there were insufficient creel vessels with a great enough dependency on Nephrops to be modelled as individual fleet segments without breaching data disclosure thresholds. However, there was employment of around 540 on a full time equivalent basis working on North Sea trawl vessels, generating around £18 million in gross value added and landing around 9,000 tonnes of Nephrops. Note that the number of people working in the fishery will be higher than that shown by full time equivalence in the case where some people work part time.

The research found that for access to Nephrops fishing grounds from the perspective of maximising employment, the current allocation based on 2017 data was already near optimal given the various considerations. The distribution of fishing grounds between creel and trawl, and within these gear types could moderately increase total employment for the Nephrops fishing fleet, which in 2017 employed 1,264 on a full time equivalent basis. The research shows that redistributing access to fishing grounds to maximise employment could increase employment by around 10%. This comprises additional employment of 88 for Nephrops creel vessels (41% increase) and 75 for trawl vessels (7% increase), both on a full time equivalent basis. 

The research shows that there is scope to increase gross value added by redistributing access to fishing grounds. In particular, an additional £14 million of gross value added may be achieved if fishing access was redistributed to maximise gross value added. This is equivalent to a 39% increase in total gross value added for the Nephrops fleet. Of the £14 million in additional gross value added, £10 million would accrue to the creel fleet and £3 million to the trawl fleet. It shows that overall both fleets can gain from reallocating access to Nephrops fishing to maximise gross value added. 

While the modelled increase in gross value added is achieved by reallocating access to fishing grounds, there will be winners and losers within both the Nephrops creel and trawl fleets. For example, in some areas the optimisation model allocates very large amounts of fishing opportunities to certain fleets. Such increases may not feasibly be taken up by these fleets and these results must be carefully considered. Similarly, there are some fleets which the optimisation model moves fishing opportunities away from. While the model ensures that all fleets remain profitable, the reactions of vessel owners to different levels of profit are unknown. 

The above impacts are reduced if vessels that are identified to benefit from the reallocation of access to Nephrops fishing grounds cannot increase their effort. In this case new vessels matching the characteristics of these vessels would need to be introduced, which results in a smaller increase in gross value added – an additional £9 million (down from £14 million). Despite the use of constraints which aim to increase the realism of the outputs, sensitivities around certain variables and data may still be present. An example of this is that if the potential gains from the fleet segment with the largest increase in gross value added were removed then the overall gain in gross value added falls to £5 million (down from the £9 million above). 

The modelling also suggests that a trawling ban within 3 nautical miles of the coast (an option being promoted by some West Coast creel fishing interests) may result in an increase in gross value added of around £6 million. This is lower than the £14 million that could potentially be achieved through a more targeted reallocation of access to fishing grounds between and within the creel and trawl fleets. While a requirement to only land whole Nephrops leads to the largest potential increase in gross value added – £42 million, however this scenario would be highly sensitive to markets and price changes as it would lead to a large change in end-product composition (from tails to whole Nephrops). All of the above outcomes show that there may be opportunities to increase or change the product mix of Nephrops for a better outcome in terms of gross value added. However, the modelling assumes that there is a market to take any additional quantities at 2017 average prices. 



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