Pullet carpet shell clams are common on the coasts of Britain and Ireland, France and into the Bay of Biscay, where they are staple, traditional fare. It is an oval, bivalve shell that reaches 5 cm (2”) in length. The exterior is sculptured with concentric ridges and faint radiating lines. White, cream or grey in colour, it sometimes has purple or brown markings.
Pullet carpet shell clams occur in wave protected areas such as sheltered inlets and sea lochs or sandy beaches of the rias in Spain, flooded river valleys. It burrows to a depth of 5 cm (2”) in mixed sandy substrata, gravel or mud bottoms, often attached to small stones or shells by byssal threads. It occasionally inhabits rock crevices. It occurs from the lower shore to the lower circalittoral but is most abundant in shallow subtidal areas. I have seen one mention of going to a depth of 40 cm (16”).
Venerupis pullastra is mainly harvested in Spain, Portugal, France and Italy. In Spain and Portugal the clam fishery targets three main species: Ruditapes decussatus, locally known as 'almeja fina'; Venerupis pullastra, called 'almeja babosa'; and V. rhomboideus, called 'almeja rubia'. Total production from harvests of the natural beds in the Galician bays was estimated at 2 000 tonnes in 1990. Other production areas are Cadiz and Huelva in the south of Spain.
In Spain, early records of mollusc fishing and consumption from the 16th century are mainly about the flat oyster, and only rarely about clams, but they do mention the marketing of clams in Portugal and other places. Intensive fishing for clams began in 1926 and 1927. Digging was indiscriminate, as fishermen used prohibited tools and took clams of all sizes.
In the Galician region (Spain), fishermen harvest clams by walking the intertidal areas and using special hand shovels, or sometimes by using the rakes that are normally used for keeping the culture beds clear of seaweed. Clams may also be harvested from boats, which may vary in size between less than 1 tonne and up to 12 tonnes. Some are propelled with oars, others with outboard engines. Various collection tools are used, including the 'rastro' and the 'raño' (rake), which are operated from the boats with the help of a long handle. The closed season is from March to October, and the minimum size allowed for Venerupis pullastra is 25 mm (1”) . Some Galician areas have protected bottoms called 'parks' for the extensive culture of clams.
Fishermen bring their clams to depuration stations where they are held in tanks for at least 42 hours. The clams are then packed in net bags of 0.5 - 1 and 2 kg, and are destined to be canned or eaten fresh. They are transported by refrigerated trucks which maintain their temperature at 3-10 °C; the clams have a shelf life of 5 days.