Last updated
A clam shell (species Spisula solidissima) at Sandy Hook, New Jersey Clams on Sandy Hook beaches - panoramio.jpg
A clam shell (species Spisula solidissima ) at Sandy Hook, New Jersey

Clam is a common name for several kinds of bivalve molluscs. The word is often applied only to those that are edible and live as infauna, spending most of their lives halfway buried in the sand of the seafloor or riverbeds. Clams have two shells of equal size connected by two adductor muscles and have a powerful burrowing foot. [1] They live in both freshwater and marine environments; in salt water they prefer to burrow down into the mud and the turbidity of the water required varies with species and location; the greatest diversity of these is in North America. [2] [3] [4]


Clams in the culinary sense do not live attached to a substrate (whereas oysters and mussels do) and do not live near the bottom (whereas scallops do). In culinary usage, clams are commonly eaten marine bivalves, as in clam digging and the resulting soup, clam chowder. Many edible clams such as palourde clams are oval or triangular; [5] however, razor clams have an elongated parallel-sided shell, suggesting an old-fashioned straight razor. [6]

Some clams have life cycles of only one year, while at least one may be over 500 years old. [7] All clams have two calcareous shells or valves joined near a hinge with a flexible ligament and all are filter feeders.


Littleneck clams, small hard clams, species Mercenaria mercenaria LittleNeck clams USDA96c1862.jpg
Littleneck clams, small hard clams, species Mercenaria mercenaria

A clam's shell consists of two (usually equal) valves, which are connected by a hinge joint and a ligament that can be external or internal. The ligament provides tension to bring the valves apart, while one or two adductor muscles can contract to close the valves. Clams also have kidneys, a heart, a mouth, a stomach, and a nervous system. Many have a siphon.

Food source and ecology

A clam dish Sandiego 11 bg 010706.jpg
A clam dish
Clams simmering in a white wine sauce Clams simmering in white wine sauce.jpg
Clams simmering in a white wine sauce

Clams are shellfish that make up an important part of the web of life that keeps the seas functioning, both as filter feeders and as a food source for many different animals. [8] Extant mammals that eat clams would include both the Pacific and Atlantic species of walrus, all known subspecies of harbour seals in both the Atlantic and Pacific, most species of sea lions, including the California sea lion, bearded seals, and even species of river otters that will consume the freshwater species found in Asia and North America. [9] [10] Birds of all kinds will also eat clams if they can catch them in the littoral zone: roseate spoonbills of North and South America, [11] the Eurasian oystercatcher, whooping crane [12] and common crane, the American flamingo of Florida and the Caribbean Sea, [13] and the common sandpiper are just a handful of the numerous birds that feast on clams all over the world. Most species of octopus have clams as a staple of their diet, up to and including the giants like the Giant Pacific octopus.


Cultures around the world eat clams along with many other types of shellfish.

North America

In culinary use, within the eastern coast of the United States and large swathes of the Maritimes of Canada, the term "clam" most often refers to the hard clam Mercenaria mercenaria . It may also refer to a few other common edible species, such as the soft-shell clam, Mya arenaria and the ocean quahog, Arctica islandica . Another species commercially exploited on the Atlantic Coast of the United States is the surf clam Spisula solidissima . Scallops are also used for food nationwide, but not cockles: they are more difficult to get than in Europe because of their habit of being farther out in the tide than European species on the West Coast, and on the East Coast they are often found in salt marshes and mudflats where mosquitoes are abundant. [14] [15] There are several edible species in the Eastern United States: Americardia media, also known as the strawberry cockle, is found from Cape Hatteras down into the Caribbean Sea and all of Florida; Trachycardium muricatum has a similar range to the strawberry cockle; and Dinocardium robustum , which grows to be many times the size of the European cockle. [16] Historically, they were caught on a small scale on the Outer Banks, barrier islands off North Carolina, and put in soups, steamed or pickled. [17]

Up and down the coast of the Eastern U.S., the bamboo clam, ensis directus, is prized by Americans for making clam strips although because of its nature of burrowing into the sand very close to the beach, it cannot be harvested by mechanical means without damaging the beaches. [18] The bamboo clam is also notorious for having a very sharp edge of its shell, and when harvested by hand must be handled with great care.

On the U.S. West Coast, there are several species that have been consumed for thousands of years, evidenced by middens full of clamshells near the shore and their consumption by nations including the Chumash of California, the Nisqually of Washington state and the Tsawwassen of British Columbia. [19] [20] [21] [22] The butter clam, Saxidomus gigantea , [23] the Pacific razor clam, Siliqua patula, [24] gaper clams Tresus capax , [25] the geoduck clam, Panopea generosa [26] and the Pismo clam, Tivela stultorum [27] are all eaten as delicacies.

Clams can be eaten raw, steamed, boiled, baked or fried. They can also be made into clam chowder, clams casino, Clam cakes, stuffies, or they can be cooked using hot rocks and seaweed in a New England clam bake. On the West Coast, they are an ingredient in making cioppino and local variants of ceviche [28]



Clams are eaten more in the coastal regions of India, especially in the Konkan, Kerala, Bengal and coastal regions of Karnataka, Tamil Nadu regions.[ citation needed ]

In Kerala clams are used to make curries and fried with coconut. In Malabar region it is known as "elambakka" and in middle kerala it is known as "kakka". Clam curry made with coconut is a dish from Malabar especially in the Thalassery region. On the south western coast of India, also known as the Konkan region of Maharashtra, clams are used in curries and side dishes, like Tisaryachi Ekshipi, which is clams with one shell on. Beary Muslim households in the Mangalore region prepare a main dish with clams called Kowldo Pinde. In Udupi and Mangalore regions it is famously called as "marvai" in local tulu language. It is used to prepare many delicious dishes like marvai sukka, marvai gassi, and marvai pundi.[ citation needed ]


In Japan, clams are often an ingredient of mixed seafood dishes. They can also be made into hot pot, miso soup or Tsukudani. The more commonly used varieties of clams in Japanese cooking are the Shijimi ( Corbicula japonica ), the Asari ( Venerupis philippinarum ) and the Hamaguri ( Meretrix lusoria ).[ citation needed ]


Great Britain

The rocky terrain and pebbly shores of the seacoast that surrounds the entire island provides ample habitat for shellfish, and clams are most definitely included in that description. The oddity here is that for a nation whose fortunes have been tied to the sea for hundreds of years, 70% of the seafood cultivated for aquaculture or commercial harvesting is exported to the Continent. [29] Historically, Britain has been an island most famous of all for its passion for beef and dairy products, although there is evidence going back to before most recorded history of coastal shell middens near Weymouth and present day York. [30] (There is also evidence of more thriving local trade in sea products in general by noting the Worshipful Company of Fishmongers was founded in 1272 in London.) Present day younger populations are eating more of the catch than a generation ago, and there is a prevalence of YouTube videos of locavore scavenging, however the numbers have a long way to go before they match the numbers consumed in Mesolithic, as evidenced by the strikingly large number of shells found in said middens.

Staple favourites of the British public and local scavengers would include the razorfish, Ensis siliqua, a slightly smaller cousin of the bamboo clam of Eastern North America. [31] These can be found for sale in open air markets like Billingsgate Market in London; they have a similar taste to their North American cousin. [32] Cockles, specifically the common cockle, are a staple find on beaches in western Wales and farther north in the Dee Estuary. The accidentally introduced hard shell mercenaria mercenaria is also found in British waters, mainly those near England, and does see some use in British cookpots. The Palourde clam by far is the most common native clam and it is both commercially harvested as well as locally collected and Spisula solida, the relative of the Atlantic surf clam on the other side of the Atlantic, is seeing increased interest as a food source and aquaculture candidate; it is mainly found in the British Isles in Europe. [33]


In Italy, clams are often an ingredient of mixed seafood dishes or are eaten together with pasta. The more commonly used varieties of clams in Italian cooking are the Vongola (Venerupis decussata), the Cozza (Mytilus galloprovincialis) and the Tellina (Donax trunculus). Though Dattero di mare (Lithophaga lithophaga) was once eaten, overfishing drove it to the verge of extinction (it takes 15 to 35 years to reach adult size and could only be harvested by smashing the calcarean rocks that form its habitat) and the Italian government has declared it an endangered species since 1998 and its harvest and sale are forbidden.[ citation needed ]


In Judaism, clams are considered non-kosher (treif); but in Islam, clams are considered Halal.

As currency

Some species of clams, particularly Mercenaria mercenaria , were in the past used by the Algonquians of Eastern North America to manufacture wampum, a type of sacred jewellery; and to make shell money. [34]


One of the world's largest clam fossils (187 cm), a Sphenoceramus steenstrupi specimen from Greenland in the Geological Museum in Copenhagen Sphenoceramus steenstrupi.jpg
One of the world's largest clam fossils (187 cm), a Sphenoceramus steenstrupi specimen from Greenland in the Geological Museum in Copenhagen
Maxima clam, Tridacna maxima 2 Tridacna gigas.jpg
Maxima clam, Tridacna maxima


Not usually considered edible:

See also

Related Research Articles

Shellfish Culinary and fisheries term for exoskeleton-bearing aquatic invertebrates

Shellfish is a colloquial and fisheries term for exoskeleton-bearing aquatic invertebrates used as food, including various species of molluscs, crustaceans, and echinoderms. Although most kinds of shellfish are harvested from saltwater environments, some are found in freshwater. In addition, a few species of land crabs are eaten, for example Cardisoma guanhumi in the Caribbean. Shellfish are among the most common food allergens.

Oyster Variety of families of Mollusc

Oyster is the common name for a number of different families of salt-water bivalve molluscs that live in marine or brackish habitats. In some species, the valves are highly calcified, and many are somewhat irregular in shape. Many, but not all oysters are in the superfamily Ostreoidea.

Geoduck Species of mollusc

The Pacific geoduck is a species of very large saltwater clam in the family Hiatellidae. The common name is derived from the Lushootseed (Nisqually) word gʷídəq.

Cockle (bivalve) Family of edible marine bivalve molluscs

A cockle is an edible, marine bivalve mollusc. Although many small edible bivalves are loosely called cockles, true cockles are species in the family Cardiidae. True cockles live in sandy, sheltered beaches throughout the world. The distinctive rounded shells are bilaterally symmetrical, and are heart-shaped when viewed from the end. Numerous radial, evenly spaced ribs are a feature of the shell in most but not all genera.

Pacific razor clam Species of bivalve

The Pacific razor clam, Siliqua patula, is a species of large marine bivalve mollusc in the family Pharidae.

<i>Ensis</i> Genus of bivalves

Ensis is a genus of medium-sized edible saltwater clams, littoral bivalve molluscs in the family Pharidae. Ensis, or razor clams, are known in much of Scotland as spoots, for the spouts of water they eject while burrowing into the sand, when visible at low tide. This term may also colloquially include members of the genus Solen. Ensis magnus are known as bendies due to their slightly curved shell.

Hard clam A species of bivalve mollusc native to the east coast of North and Central America

The hard clam, also known as a quahog, round clam or hard-shellclam, is an edible marine bivalve mollusk that is native to the eastern shores of North America and Central America from Prince Edward Island to the Yucatán Peninsula. It is one of many unrelated edible bivalves that in the United States are frequently referred to simply as clams, as in the expression "clam digging". Older literature sources may use the systematic name Venus mercenaria; this species is in the family Veneridae, the venus clams.

Razor clam is a common name for long, narrow, saltwater clams, in the genera Ensis, Siliqua, Solecurtus, and Solen, including:

Atlantic jackknife clam Species of bivalve

The Atlantic jackknife clam, Ensis leei, also known as the bamboo clam, American jackknife clam or razor clam, is a large edible marine bivalve mollusc found on the North American Atlantic coast, from Canada to South Carolina. The species has also been introduced to Europe. The name "razor clam" is also used to refer to different species such as the Pacific razor clam or Razor shell.

Common slipper shell Species of gastropod

The common slipper shell,, has many other common names, including common Atlantic slippersnail, boat shell, quarterdeck shell, fornicating slipper snail, Atlantic slipper limpet and it is in Britain as the "common slipper limpet". This is a species of medium-sized sea snail, a marine gastropod mollusc in the family Calyptraeidae, the slipper snails and cup and saucer snails.

Common cockle Species of bivalve

The common cockle is a species of edible saltwater clam, a marine bivalve mollusc in the family Cardiidae, the cockles. It is found in waters off Europe, from Iceland in the north, south into waters off western Africa as far south as Senegal. The ribbed oval shells can reach 6 centimetres (2.4 in) across and are white, yellowish or brown in colour. The common cockle is harvested commercially and eaten in much of its range.

The pod razor is a coastal bivalve of European waters. It is edible and has been fished commercially, especially in Portugal, Spain, Ireland and Scotland.

<i>Venerupis philippinarum</i> Species of bivalve

Venerupis philippinarum is an edible species of saltwater clam in the family Veneridae, the Venus clams.

<i>Leukoma staminea</i> Species of bivalve

Leukoma staminea, commonly known as the Pacific littleneck clam, the littleneck clam, the rock cockle, the hardshell clam, the Tomales Bay cockle, the rock clam or the ribbed carpet shell, is a species of bivalve mollusc in the family Veneridae. This species of mollusc was exploited by early humans in North America; for example, the Chumash peoples of Central California harvested these clams in Morro Bay approximately 1,000 years ago, and the distinctive shells form middens near their settlements.

Grooved carpet shell Species of bivalve

The grooved carpet shell, or Palourde clam, Ruditapes decussatus, or Venerupis decussatus, is a clam in the family Veneridae. It is distributed worldwide and due to its ecological and economic interest has been proposed as a bioindicator.

Aquaculture in Alaska is dominated by the production of shellfish and aquatic plants. These include Pacific oysters, blue mussels, littleneck clams, scallops, and bull kelp. Finfish farming has been prohibited in Alaska by the 16.40.210 Alaskan statute, however non-profit mariculture continues to provide a steady supply of aquaculture in the state. Many organizations that helped the ban, now encourage the growing of shellfish and other oysters.

Geoduck aquaculture

Geoduck aquaculture or geoduck farming is the practice of cultivating geoducks for human consumption. The geoduck is a large edible saltwater clam, a marine bivalve mollusk, that is native to the Pacific Northwest.


  1. "Clam". Encyclopædia Britannica. Encyclopædia Britannica. 2016.
  5. "Clams recipes". BBC. Retrieved 23 February 2017.
  6. "Clam". Oxford Dictionaries – Dictionary, Thesaurus, & Grammar.
  7. Danielle Elliot (14 November 2013). "Ming the Clam, World's Oldest Animal, Was Actually 507 Years Old". CBS News. Retrieved 15 November 2013.
  14. "harvesting cockles". Archived from the original on 2018-03-16. Retrieved 2018-03-16.
  15. "Cockle". SeafoodSource. Diversified Communications. 23 January 2014.
  16. "Untitled Document". Retrieved 2020-09-26.
  17. Smith, Prudence (1831). Modern American Cookery ... With a list of family medical recipes, and a valuable miscellany.
  18. "dredging of clams" (PDF).
  19. "Shell Midden Analysis". Retrieved 2018-03-10.
  20. "Nisqually People and the River – Yelm History Project". Retrieved 2018-03-10.
  21. "What Did the Chumash Eat? | Synonym" . Retrieved 2018-03-10.
  22. "Tsawwassen First Nation History and Timeline". Tsawwassen First Nation. November 10, 2011.
  23. "Plenty of clams, oysters in Puget Sound and Hood Canal". The Seattle Times. 2015-06-27. Retrieved 2018-03-10.
  24. Kelly, Mike. "Dig Those Razor Clams". North Coast Journal. Retrieved 2018-03-10.
  25. Lackner, Bill. "Oregon clam chowder". Coos Bay World. Retrieved 2018-03-10.
  26. "All About Geoduck: The Life of a (Delicious) Oversized Mollusk". Retrieved 2018-03-10.
  27. "Digging for Pismo clams at San Diego Beaches" . Retrieved 2018-03-10.
  28. "razor clams | Langdon Cook". Retrieved 2018-03-16.
  30. Thomas, Ken; Mannino, Marcello (1998). "Mesolithic middens and molluscan ecology: A view from southern Britain". Archaeology International. 2: 17. doi: 10.5334/ai.0207 .
  33. Joaquim, Sandra; Matias, Domitília; Matias, Ana Margarete; Gonçalves, Rui; Chícharo, Luís; Gaspar, Miguel B. (2016). "New species in aquaculture: Are the striped venus clam Chamelea gallina(Linnaeus, 1758) and the surf clam Spisula solida(Linnaeus 1758) potential candidates for diversification in shellfish aquaculture?". Aquaculture Research. 47 (4): 1327–1340. doi:10.1111/are.12593.
  34. Kurlansky, Mark (2006), The Big Oyster: History on the Half Shell, Penguin Group, pp.  16, 30–31, ISBN   978-0-345-47638-8, OCLC   60550567.