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Shellfish reefs – physical habitats built by the accumulation of
masses of mollusk shells – may be the world’s most threatened
marine habitats. Once widespread in estuaries and lagoons, a con-
servative estimate suggests that 85% have been lost to overfishing,
poor river basin management and pollution1 (Beck
et al
., 2009).
The value of shellfish for food has been recognized for millennia,
however it is only in recent decades, as the resources have be-
come scarce, that other services provided by shellfish reefs have
been realized. Through their complex structure, shellfish reefs
greatly enhance commercially important fish and crab stocks. In
sufficient quantities they can measurably reduce nitrates and tur-
bidity in coastal waters. In so doing they also allow growth and
Shellfish Reefs United States oyster restoration case study –
enhancing fisheries
recovery of other important habitats such as seagrasses. In some
locations the large physical structures of shellfish reefs even protect
coasts from wave action. Such services are of growing social, eco-
nomic and political relevance as pollution and sea level rise are of
increasing concern world-wide.
In the US, recognition of these valuable services has led to a surge
in interest in the restoration of oyster reefs nation-wide. The fed-
eral National Oceanic and Atmospheric Administration, through
numerous partnerships, has supported over 128 oyster and shell
bottom restoration projects in twenty states since 1998. Many other
restoration efforts have been undertaken by state agencies, NGOs
and community groups.
CASE STUDY #21
Communities on the east Virginia coast have a long history of
oyster harvesting, however the eastern oyster
Crassostrea vir-
ginica
finally became commercially extinct in the region in the
early 1990’s. In 2006 a public-private community partnership
was formed between the Virginia Marine Resources Commis-
sion and The Nature Conservancy which, in collaboration with
local businesses and community volunteers, made significant
steps to restoring oyster reefs in Smith Island Bay. Local con-
tractors dredged over 1188 tonnes of fossil shell, depositing
them in shallow areas to form two ~0.8 ha reefs. The rapid
colonization and growth of new oysters on the reefs has cata-
lyzed further restoration projects. To date the larger Seaside
Bays Restoration Project on the Virginia Coast, of which Smith
Island Bay is a part, has successfully restored 1.7ha of intertidal
oyster reef, with a further 5.5ha planned. An estimated 47 jobs
will be maintained or created by oyster restoration work as a
result of this project.
Virginia Coast restoration sites are continually monitored, and
have been showing significant recruitment since their construc-
tion. Research is being undertaken to determine the filtration
Virginia Coast restoration sites