Eastern Oyster Drill
Urosalpinx cinerea
Summary 3
Urosalpinx cinerea, common name the eastern or Atlantic oyster drill, is a species of small predatory sea snail, a marine gastropod mollusk in the family Muricidae, the murexes or rock snails.
Description 4
The shell of Urosalpinx cinerea is knobby having rugged whorls (turns of the shell) with rounded shoulders usually numbering 5. Each complete turn of the Atlantic oyster has 9-12 vertical, rounded ribs crossed with 15 rows of thinner spiral ridges. The aperture (opening through which the snail moves in and out of the shell) of U. cinerea is oval with an open canal at the base. Shells are usually yellow sometimes orange, grey or white and occasionally bearing brown streaks. The interior of the shell can be purple, red-brown or yellow. The operculum (the plate that closes to protect the snail when it is inside its shell) can be orange or yellow-brown.U. cinerea, a mollusk in the family Muricidae, is considered a major pest among the world's bivalve fisheries (Robinson and Dillon 2008). In colder waters, this species will be dormant throughout the winter and emerge in April to feed (Franz 1971).
Food habits 5
Food usually consists of oysters and other mollusks. This makes Urosalpinx cinerea a carnivore. It prefers to prey upon smaller softer shelled oysters, which are much easier to penetrate and eat. They are usually stationary or somewhat mobile filter feeders that remain in set stationary breeding or living beds located on the floor of the shoreline. Urosalpinx cinerea crawls over the beds finding small oysters. It then grips the shell with its foot, which secretes a softening agent and uses its drill, called a radula, in a mechanical process to break through the prey's shell. Once this occurs Urosalpinx cinerea inserts its proboscis into the oyster, which then secretes a muscle relaxer into the prey causing the oyster to open exposing the animal inside. (Morton, 1958 ; Buchsbaum & Pearse, 1987 ; Nichols & Cooke, 1979)
After drilled, a total of one fourth of the oyster's tissue remains inside. This tissue consists of the adductor muscle, various soft parts, and the gills. The muscle destruction of the oysters caused by the drill was found to range from none to total destruction. However, it was found that in 90% of the oysters studied, at least half of the adductor muscle was destroyed. The oyster drills exhibited a clear preference when eating consisting of various soft tissues, the gills, and the adductor muscle allowing the oyster drills to eat as long as possible on one oyster before it gapes allowing other predators to feed upon it. Urosalpinx cinerea drills the oysters through the central portion of the valve and not at the margin of the valves. (Chapman, 1955)
Habitat 6
Urosalpinx cinerea usually dwell on rocks or in the sand along the coast and in bays. (Nichols & Cooke, 1979) Urosalpinx cinerea is found anywhere oysters flourish. They are most abundent in intertidal zones and shallow water areas including estuaries, marshes, and bays. Urosalpinx cinerea especially enjoys these waters when there is a relatively high salinity content. Usually, the greater the salinity content the more this species will thrive at a specific location. (Beal, 1993 ; NOAA, 2000)
Aquatic Biomes: coastal
Sources and Credits
- (c) Paul Morris, some rights reserved (CC BY-SA), http://www.flickr.com/photos/32161280@N06/5038902228
- (c) Ken-ichi Ueda, some rights reserved (CC BY), uploaded by Ken-ichi Ueda
- Adapted by Marisa Rafter from a work by (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Urosalpinx_cinerea
- (c) Smithsonian Marine Station at Fort Pierce, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/11526964
- (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/18678386
- (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/18678383
