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 fishing bait.

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 appear.

The most commonly collected shoreline species

Phylum

Family

Common & scientific names

Summary of life history and ecology

Polychaeta

(Bristle worms)

Nereidae, Ragworms Harbour rag Hediste (Nereis) diversicolor

King rag Neanthes (Nereis) virens

Ragworm Perinereis cultrifera

Free-living, 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.
Nephtyidae, Catworms or silver rag Nephtys caeca

Nephtys cirrosa

Nephtys hombergi

Catworms 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.
Arenicolidae, Lugworms Blow lug, lobworm or yellowtail Arenicola marina

Black lug or runnydown Arenicola defodiens

Lugworms 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 farms.
Crustacea Portunidae

 

 

 

 

 

Cancridae

Shore crab or green crab Carcinus maenas

Velvet fiddler or velvet swimming crab Necora puber

Edible crab Cancer pagurus

Crustacea 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.
Mollusca Class Gastropoda Subclass Prosobranchia Molluscs usually characterised by a single coiled shell, sealed by a horny operculum attached to the top of the animal’s foot.
Littorinidae, Winkles Common periwinkle Littorina littorea Winkles 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.
Mollusca Class Bivalvia Predominantly sedentary with planktonic larvae. Adults live attached to fixed substrata, in crevices, or burrowing in bottom sediments.
  Mytilidae, Mussels Common mussel Mytilus edulis Live 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.
Ostreidae, Oysters Flat oyster Ostrea edulis

Pacific oyster Crassostrea gigas

Formerly 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.
  Cardiidae, Cockles Common cockle Cerastoderma edule Common 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.
Veneridae, Venus or carpet shells Quahog Mercenaria mercenaria A 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.
  Solenidae, Razor shells Common razor shell Ensis ensis Large (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.
Myacidae, Gaper shells Sand gaper, or soft shell clam Mya arenaria Large (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.
(See Appendix for more detailed information on these and other species.)

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