A knobbed whelk's underside is seen on its exhibit window as it sticks to the window.

Species Name: Busycon carica

In addition to being a source of food for loggerhead sea turtles and keeping bivalve populations in check, this sea snail is popularly found in human cuisine from fritters to chowders and even in salads. The whelk shell, like the similar conch shell, has long been used in certain cultures as a horn for ceremonial or communication purposes.

About Green Moray Eels

Length: Up to 1 foot in length or more.

This gastropod is a large predatory sea snail and one of 50 species of whelks. Their thick ivory shells have 6 coils that spiral clockwise, with an "aperture" or inside area of the wide opening that is usually orange. Knob-like protrusions emerge from the widest part of the coil, giving the species its name. The shell of most knobbed whelks is "dextral," in which the opening of the shell is on the animal's right side if you were to hold the shell up with the spiral end upward and the opening facing you. A left-hand opening in the shell is called "sinistral."

Diet

Knobbed whelks forage on intertidal flats and in creeks edged with oyster reefs, preying on bivalves like oysters, scallops, and clams.

Habitat

Knobbed whelks thrive in the sub-tidal zone but will migrate between deep and shallow water, depending on the season. During seasons of extreme temperature like summer and winter, these sea snails migrate further out to depths of 48 meters. During milder spring and fall months, they are more commonly found in shallow water in intertidal mud and sand flats. It is during this time that mating and egg-laying occur. Since they must remain most, they avoid the mid-day heat by burrowing into the sand.

Feeding

Knobbed whelks use the edge of their shells to pry open the shells of their bivalve pry, then rasp at the flesh using a rough, tongue-like organ called a "radula" that has thousands of tiny tooth-like protrusions known as "denticles."

Reproductive Behavior

Knobbed whelks reproduce internally, then create a string of "egg capsules" that hold 20-100 eggs each. Some strings can reach up to 3 feet in length.

The knobbed whelk is not considered at risk of population decline currently, and so they are not evaluated, and thereby classified as Data Deficient by the IUCN.

Resident Knobbed Whelks

A knobbed whelk sits near the window of its exhibit.

Chesapeake Bay Touch Pool Whelks

Our whelks are ready to greet you from their home in the Cheseapeake Bay Touch Pool!

IUCN Classification

Data Deficient IUCN Red List Icon

Data Deficient (DD)

A taxon is Data Deficient (DD) when there is inadequate information to make a direct or indirect assessment of its risk of extinction baased on its distribution and/or population status. A taxon in this category may be well studied, and its biology be well known, but appropriate data on abundance and/or distribution are lacking.

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