Throughout much of the UK and in Europe generally the native oyster is in a
severely depleted state in the wild. In order to address and potentially to
reverse this situation Ostrea edulis was designated as a named species in the UK
Biodiversity Action Plan as part of a national commitment to the
International Convention on Biodiversity. Amongst other initiatives, some of
which are summarised in this paper, a feasibility study was carried out to
evaluate all the factors, including an economic assessment, relevant to a
programme of stock restoration in the UK. The study showed that there is a
considerable body of data on the biology, ecology and distribution of O. edulis to
inform restoration projects. Appropriate legislation is in place to allow
for restoration. Non-marketable costs and benefits were estimated. They
provide an idea of the high value that may be placed on biodiversity
aspects. Nevertheless, this study also shows that stock restoration can be
commercially viable if fishery prices and yields are sufficiently high.
Restoration efforts and associated studies elsewhere have shown the
potential for success of native oyster stock regeneration, especially in
disease-free areas. For these, there is a very strong element of re-creating
and conserving an ecological resource. The relaying of cultch is seen as an
essential component of a successful oyster restoration programme and the use
of sanctuaries is generally considered beneficial. The loss of the standing
stock is a limiting factor and re-stocking is an effective strategy. There
is a basic genetic similarity of wild European O. edulis populations such that the
source of stocks is not critical. There are some problems with hatchery
rearing from these, but using breeding ponds or importing part-grown oysters
are viable alternatives.