A bioeconomic analysis of the UK fisheries of the English Channel.
The purpose in this thesis was to undertake a bioeconomic analysis of the fisheries of the
English Channel. An economic survey of the fishery was undertaken to establish the
economic and financial performance of the various fleet segments in the fishery in 1994-95. It
was found that the fishery as a whole was producing negligible levels of resource rent,
although some boat owners were receiving intra-marginal rents.
Long run equilibrium models of sole and plaice were developed and the optimal (profit
maximising) level of effort (in beam trawl hours equivalent) was estimated. It was found that
the optimal level of effort was substantially lower than the current level of effort expended on
these two species. A method for estimating surplus production models which incorporate
decreasing returns to effort was also developed and applied to the fishery.
A linear programming (LP) model was also developed which incorporate the multi-species
and multi-gear features of the fishery. The model was used to estimate the maximum level of
profits that could be achieved in the fishery given existing stock conditions. It was found that
profits could be increased substantially, but at the cost of a large reduction in fishing
employment. A compromise `optimal' was estimate using multi-objective (goal
The LP model was also used to estimate the effects of a restriction on days at sea and reduced
total allowable catches of sole and plaice. It was estimated that these policies would impose
additional costs on various segments of the fishery, particularly the trawl segments to which
they are targeted. Benefits, if any, were likely to be negligible as the policies were estimated
to result in increased discarding rather than decreased catch. The model results suggest that
the long term level of effort may be more effectively reduced through implementing a charge
on access to, or use of, the resource.