Species most commonly collected
The vast majority of non-commercial
collection of species from sediment shores in the
UK is undertaken to provide fishing bait. The most
common target species are burrowing polychaete worms,
listed in the table below. Some burrowing bivalves
are also collected from sediment shores, mainly
for human consumption although razor shells and
possibly others are also used for bait. In the UK,
the cockle is the most widely collected and consumed,
but there is potential for a much wider range of
bivalves to be utilised more regularly (examples
are also listed in the table below). The collection
of common shore crabs from sediment shores for fishing
bait is increasing.
Rocky shores are primarily used
for the collection of crabs (several species, taken
primarily for fishing bait) winkles (and to a lesser
extent, a few other large gastropod molluscs), and
mussels for human consumption and sometimes for
It is only the inherently conservative
nature of the British diet that has restricted the
species collected for food from the intertidal.
Elsewhere in Europe and other parts of the world,
a much wider range of species is taken. As the cultural
diversity of British communities increases, site
managers may expect to find an increasingly large
number of species being taken, mirroring the observations
made of collection on shores in south-eastern Australia
(see Underwood 1993 and the New South Wales case
study in the Appendix).
This will be particularly likely in coastal areas
close to the largest and most ethnically-diverse
centres of population. The Appendix
also, therefore, attempts to draw attention to species
and groups of species that are currently under-utilised,
or which have the potential to be collected in the
future, or examples of species from families or
genera with potential for collection. A few predominantly
sublittoral species of high value and commercial
importance are also listed, but most of the taxonomic
groups that are not collected on the shore do not
The most commonly collected shoreline
Common & scientific names
Summary of life history and
rag Hediste (Nereis) diversicolor
King rag Neanthes (Nereis) virens
Ragworm Perinereis cultrifera
omnivorous, fast-growing worms which breed only
once in their lifecycle before dying. They are
farmed commercially for bait. Sexes are separate,
and all mature worms spawn on the same day.
Some mature after one year, but wild king ragworms
are usually two or three years old at maturity.
Usually one third or more of the population
breeds each year and recruitment to the population
is rapid. Some populations have much larger,
older worms. These reproduce slowly and are
more vulnerable to over-collection.
Catworms or silver rag
actively swim and burrow in clean sand beaches
in search of prey. They are long-lived, have
separate sexes, and may breed several times
in a lifetime. All mature worms in a population
breed on the same day, but not always every
year. Larvae spend up to 5 weeks in the plankton
before settling onto the bottom. An average
3 inch worm is usually 4-5 years old. The largest
may be up to 12 years old. Large worms are highly
valued by match anglers. Their slow growth,
infrequent spawning and low recruitment rates
make them vulnerable to over-collection. Research
into farming is underway.
lug, lobworm or yellowtail Arenicola marina
Black lug or runnydown Arenicola defodiens
live in U or J-shaped burrows on sandy and muddy
sand shores and in the sublittoral, and feed
on decaying seaweed, diatoms and bacteria. Sand
casts are left above one burrow entrance. They
begin to breed and are large enough for bait
at 2 years old, and may live for 6 years reaching
weights of 10 g (NE England) to 25 g (south
and west). They breed several times during their
life. Each worm spawns in a day, and all worms
on a beach spawn within a few days, but those
on different beaches spawn at different times.
Some worms die after spawning. Others stop feeding
and casting until their larvae leave the adult
burrow to spend 6 months below the low water
mark. They then swim to upper shore juvenile
lugworm beds. Maturing worms move down the shore
to adult beds. This life cycle makes most lugworm
populations able to recover quickly from over-digging.
Both species should soon be available from bait
crab or green crab Carcinus maenas
Velvet fiddler or velvet swimming crab
Edible crab Cancer pagurus
grow by regularly moulting their external shells
and expanding before the new shell has hardened.
Crabs entering the moult are called peelers
and soft shell crabs after moulting
and before hardening. Peeler crabs release hormones
that attract fish (making them very valuable
as bait) so hide under rocks or other shelters
to escape predators during these vulnerable
stages. Bait collectors take peeler crabs of
all species, including commercially fished species,
but the common shore crab Carcinus maenus
is most abundant and widely used. This species
is also collected for human consumption in many
parts of Europe, and for fun by crabbing
children. Minimum landing sizes apply to velvet
and edible crabs.
Gastropoda Subclass Prosobranchia
usually characterised by a single coiled shell,
sealed by a horny operculum attached to the
top of the animals foot.
periwinkle Littorina littorea
are common mid and low tide levels on almost
all rocky shores, except on some islands. An
important source of food in prehistoric times,
but now mainly exported to the Continent. UK
harvests are probably over 2,000 tonnes per
annum. Harvesting reduces numbers and average
size. Winkles usually mature at a shell height
of 11-12 mm, and are harvested from 14-15 mm.
Maximum size is 32 x 25 mm. Large winkles
are infected by trematodes, reducing egg production,
and small winkles may naturally yield most egg
production. Planktonic egg capsules are laid,
so recruitment to the shore may not be from
a local population.
sedentary with planktonic larvae. Adults live
attached to fixed substrata, in crevices, or
burrowing in bottom sediments.
mussel Mytilus edulis
in small groups on rocky shores or in dense
beds on sediment habitats. An important food
since prehistory. Collection for fishing bait
is now only a fraction of levels 100 years ago.
Most commercial collection is from wild stocks
in sediment areas (sometimes using relayed wild
seed), but there is some mussel cultivation.
Length usually 50-100 mm, but sometimes
only up to 30 mm, or as much 150 mm.
Preferred minimum size for sale in the UK is
about 55 mm. Wild mussels in Scotland are
royal shellfish and Crown property.
oyster Ostrea edulis
Pacific oyster Crassostrea gigas
very common, native flat oysters have virtually
disappeared in the UK because of disease, habitat
damage and over-exploitation. Introduced Pacific
oysters sometimes breed and settle naturally
onto the lower shore in the south and west.
Most populations are artificially laid for culture
and protected by Several Order in England and
Wales, or through their status as royal shellfish
in Scotland, where Crown Estate permission is
required for their collection.
cockle Cerastoderma edule
on all UK coasts and estuaries in sandy muds,
sands and fine gravels from mid tide level to
just below the extreme low water mark of spring
tides. Sometimes found in extremely dense beds,
and often associated with bait worms. Collected
commercially by hand and mechanically, and by
hand for personal consumption.
Venus or carpet shells
large (to 120 mm) and valuable edible bivalve,
introduced into the UK from the USA and found
on the lower shore and in shallow sublittoral
muddy habitats. Exploited for personal use and
commercially, by hand digging and dredge.
razor shell Ensis ensis
(up to 130 mm long) bivalve actively burrowing
in fine sand on the lower shore and shallow
sublittoral. Traditionally hand collected for
food and bait for personal use and for resale
(usually exported for food to Europe). Recently
harvested by suction dredger.
gaper, or soft shell clam Mya arenaria
(up to 150 mm long) bivalve of high commercial
importance in parts of the world (used in American
clam chowder). May be extremely common in estuaries,
where extensive beds are sometimes found, but
apparently not widely harvested in the UK.
Appendix for more detailed information on these and other species.)