You have probably never seen a living whelk. Nevertheless, the whelk is a large sea snail belonging to the normal benthic fauna of the North Sea. It lives at deeper sea depths. You usually only find the empty shells on the beach sometimes occupied by a hermit crab. This snail is very sensitive to overfishing, churning up of the sea floor and toxins, such as tributyltin. Due to a combination of all these factors, the whelk has practically disappeared from the Dutch coastal region and the Wadden Sea.

This whelk is carnivorous, and feeds on polychaete worms and other molluscs, such as bivalves. It uses the edge of its shell to prize open bivalve shells (2), and may drill holes into the shell of its prey in order to access the soft tissues inside. It also scavenges for carrion, which it detects by smell from some distance (2). When searching for food, whelks extend a tube known as the 'siphon', which is used to funnel water to the gills, and leads to a sensory organ used for smelling prey (4). The sexes are separate; breeding takes place from October to May, and the eggs are attached to rocks, shells and stones in protective capsules. Each capsule contains as many as 1000 eggs, and the capsules of several females are grouped together in large masses of over 2000 (2). Only a few of these eggs will develop; most eggs are used as a source of food by the growing embryos (3). There is no free-swimming larval stage (4), instead, crawling young emerge from the capsules after several months (3). Empty egg masses frequently wash up on beaches, and are often mistaken for sponges (2). They are known as 'sea wash balls' because they were once used to wash with (3). Common whelks are thought to live for 10 years. They are fished commercially using traps; most whelks are exported to the Far East (2).

This large, common whelk has a stout, yellowish-brown shell with lighter and darker spiral areas (3). It has 7-8 whorls, and a large oval aperture (opening), which tapers to a point (3).

 A large whelk up to 10 cm high and 6 cm wide. The shell has 7-8 whorls with spiral ridges. The shell is yellowish brown with irregular light and dark spiral areas. The aperture is broadly oval tapering to a point with a short wide siphonal canal leading from the base of aperture.There is a significant fishery, which uses traps, for common whelks. The majority of the whelks are exported to the far east. Masses of lentil shaped eggs are often found attached to subtidal rocks, stones or shells. Empty egg masses, known as 'sea wash balls', are often found on the strandline and are sometimes mistaken for sponges. Buccinum undatum may be confused with the red whelk Neptunea antiqua. Neptunea antiqua does not have the coarse ribbing of Buccinum undatum and is not edible.

Atlantic, Baltic sea, Bar Road, Bay of Biscay, Belgian Exclusive Economic Zone, Brier Island, British Isles, Canada, Canadian part of the Arctic Ocean, Clam Cove, Cobscook Bay, De Haan, De Panne, Deadmans Harbour, Digby, Dutch Exclusive Economic Zone, European waters (ERMS scope), German Bight, Goote Bank, Grevelingen, Gulf of Maine, Gulf of St. Lawrence, Icelandic Exclusive Economic Zone, Irish Exclusive economic Zone, L'Etete, Lorneville Harbour, Minas Basin, Minister's Island, North Coast of Norway, North East Atlantic, North Sea, North West Atlantic, Oostduinkerke, Oostende, Oosterschelde, Portuguese Exclusive Economic Zone, Saguenay Fjord, Spanish Exclusive Economic Zone, Spuikom, St. Lawrence Estuary, Swedish Exclusive Economic Zone, The Wolves, United Kingdom, United Kingdom Exclusive Economic Zone, USA, Wadden Sea, West Coast of Norway , Wimereux

The waved whelk, or common northern whelk, can be found in the North Atlantic along the coastline of North America from New Jersey northward, the coastline of Greenland, the coastline of Europe from France northward, the coastlines of Norway, the British Isles, Iceland, and the coastlines of some islands in the Arctic Ocean (George and George 1979, Grzimek 1972, Ghiselin 2000).

Biogeographic Regions: arctic ocean (Native ); atlantic ocean (Native )

Range: 76°N to 36.8°N; 83°W to 0°W. Distribution: Greenland; Greenland: West Greenland; Canada; Canada: Queen Elizabeth Islands, Baffin Island, Labrador, Newfoundland, Quebec, New Brunswick; USA: Maine, Massachusetts, Connecticut, New York, New Jersey, Delaware, Maryland, Virginia

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Common around all coasts of Britain (3), it also has a wide distribution in northwest Europe (2).

The marbled body of the whelk is encased in a calcified shell, which ranges from 6-10 cm in length. The shell is spiraled, and lacks the nacreous surface layer of some other gastropods. The body is composed of three basic parts: the foot, the head, and a visceral mass. The foot extends from the shell next to the head and is used for locomotion and grasping prey or a substrate when feeding on algae. The head includes a mouth, from which the radula, an elongated tongue-like apparatus bearing three central teeth and two rows of transverse teeth, is extended for feeding. There are also two cephalic tentacles which have some tactile sensation. These tentacles and the osphradia, a structure that does not emerge from the shell but is positioned at the end of a siphon pointing in the direction of the current, have chemoreceptors which aid in scavenging. Whelks are either male or female, with gonads positioned deep within the shell behind the body because of the torsion of the spiral shell. Males of the species have a penis for sperm transfer (George and George 1979, Grzimek 1972, Brusca 1990).

Waved whelks occupy coastlines within the range described above from the tide level to 180 meters depth. They live in the mud and sand of these areas on the ocean floor (Ghiselin 2000, George-George 1979, Grzimek 1972, Anderson 1988).

Aquatic Biomes: coastal

Known from rocky shores.

intertidal, bathyal, infralittoral and circalittoral of the Gulf and estuary

Depth range based on 1043 specimens in 1 taxon.
Water temperature and chemistry ranges based on 650 samples.

Environmental ranges
  Depth range (m): -2.2 - 549
  Temperature range (°C): -0.262 - 12.552
  Nitrate (umol/L): 0.660 - 22.184
  Salinity (PPS): 22.343 - 35.343
  Oxygen (ml/l): 3.835 - 8.193
  Phosphate (umol/l): 0.064 - 1.647
  Silicate (umol/l): 0.987 - 17.288

Graphical representation

Depth range (m): -2.2 - 549

Temperature range (°C): -0.262 - 12.552

Nitrate (umol/L): 0.660 - 22.184

Salinity (PPS): 22.343 - 35.343

Oxygen (ml/l): 3.835 - 8.193

Phosphate (umol/l): 0.064 - 1.647

Silicate (umol/l): 0.987 - 17.288
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

 Occasionally intertidal but mainly subtidal down to 1200 m. Found on muddy sand, gravel and also rock. Sometimes present in brackish waters.

Found from the extreme low water mark of the intertidal zone down to depths of 1200m (3). It lives on soft sediments including muddy sand and gravel as well as on rocks (3).

 

The species associated with this article partially comprise the benthic community of Stellwagen Bank, an undersea gravel and sand deposit stretching between Cape Cod and Cape Ann off the coast of Massachusetts. Protected since 1993 as part of the Stellwagen Bank National Marine Sanctuary, the bank is known primarily for whale-watching and commercial fishing of cod, lobster, hake, and other species (Eldredge 1993). 

The benthic community of Stellwagen Bank is diverse and varied, depending largely on the grain size of the substrate. Sessile organisms such as bryozoans, ascidians, tunicates, sponges, and tube worms prefer gravelly and rocky bottoms, while burrowing worms, burrowing anemones, and many mollusks prefer sand or mud surfaces (NOAA 2010). Macroalgae, such as kelps, are exceedingly rare in the area — most biogenic structure along the bottom is provided by sponges, cnidarians, and worms. The dominant phyla of the regional benthos are Annelida, Mollusca, Arthropoda, and Echinodermata (NOAA 2010). 

Ecologically, the Stellwagen Bank benthos contributes a number of functions to the wider ecosystem. Biogenic structure provided by sessile benthic organisms is critical for the survivorship of juveniles of many fish species, including flounders, hake, and Atlantic cod. The benthic community includes a greater than average proportion of detritivores — many crabs and filter-feeding mollusks — recycling debris which descends from the water column above (NOAA 2010). Finally, the organisms of the sea-bed are an important source of food for many free-swimming organisms. Creatures as large as the hump-backed whale rely on the benthos for food — either catching organisms off the surface or, in the whale’s case, stirring up and feeding on organisms which burrow in sandy bottoms (Hain et al 1995). 

As a U.S. National Marine Sanctuary, Stellwagen Bank is nominally protected from dredging, dumping, major external sources of pollution, and extraction of mammals, birds or reptiles (Eldredge 1993). The benthic habitat remains threatened, however, by destructive trawling practices. Trawl nets are often weighted in order that they be held against the bottom, flattening soft surfaces, destroying biogenic structure, and killing large numbers of benthic organisms. There is also occasional threat from contaminated sediments dredged from Boston harbor and deposited elsewhere in the region (NOAA 2010). The region benefits from close observation by NOAA and the Woods Hole Oceanographic Institute, however, and NOAA did not feel the need to make any special recommendations for the preservation of benthic communities in their 2010 Management Plan and Environmental Assessment. 

The waved whelk is a carnivore, and feeds on crabs, polychaete worms, bivalves, and dead organisms. Water enters the siphon which is pointed in the direction of the current and the osphridia's chemoreceptors detect for prey. The whelk moves to the prey using its foot, and uses it to grasp the shell in the case of a crab or bivalve. The radula is extended from the mouth and if the prey has a shell, the radula's teeth are used to drill a beveled hole through which the radula can extract the body matter. Radular teeth of whelks are solid and do not contain poison as in the case of cones, but the tongue may confer a secreted acidic mucus to the shell that is being bored. Digestion is primarily extracellular and takes place within a digestive gland at the end of a long esophagus that empties into a stomach (Anderson 1988, Alexander 1979, Brusca 1990, Ghiselin 2000).

Sexes are separate, and the male has a penis which transfers sperm to the female, where internal fertilization occurs. There are two types of sperm produced by the male whelk. The first is the viable euspermatozoa, which are the functional gametes that will unite with the egg in the reproductive tract of the female. Accompanying these are paraspermatozoa, which have multiple external tails and help to control and assist in the movement of the viable sperm, as well as provide them with nutrients. After fertilized eggs emerge from the oviduct, they are coated in mucus and approximately 1000 are contained in a flexible capsule. These capsules are then released into piles. Of the 1000 eggs in a capsule, only about 10 undergo full development, the rest providing nutrition. Snails hatch from these capsules fully developed (Anderson 1988, Grzimek 1972).

The following is a representative barcode sequence, the centroid of all available sequences for this species.


There is 1 barcode sequence available from BOLD and GenBank.   Below is the sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.  See the BOLD taxonomy browser for more complete information about this specimen.  Other sequences that do not yet meet barcode criteria may also be available.


Download FASTA File

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 1
Specimens with Barcodes: 5
Species With Barcodes: 1

The northern whelk is found readily in along the coasts of its geographic range in large numbers, especially in North America, probably due in part to its excellent and complex reproductive adaptations (Anderson 1988, Ghiselin 2000, U.S. Fish and Wildlife 2000, Sea World Education Dep. 2000).

US Federal List: no special status

CITES: no special status

United States

Rounded National Status Rank: NNR - Unranked

Rounded Global Status Rank: GNR - Not Yet Ranked

Common and widespread; not listed under any conservation designations (2).

This species is currently widespread and not threatened.

Conservation action has not been targeted at this species.

N/A

On the coast of North America fishermen often use the body of the whelk without the shell as bait for cod. In the past fishermen have been known to use the egg capsule of the whelk as "sea soap" to clean their hands. In Europe and Scandinavia the waved whelk serves as a food source for humans. We also receive the indirect benefit of the scavenging habits of the whelk in the disposal of carrion on the ocean floor (Grzinek 1972, Brusca 1990).