Introduced Species Summary Project
Rough Periwinkle (Littorina saxatilis)
Scientific Name: Littorina saxatilis
Phylum or Division: Mollusca
Identification: A small (up to 18mm in height and 14mm wide), ovoviviparous, dioecious, herbivorous snail occurring either in off-white, greenish, reddish or brown colors. The aperture of the shell is large, rounded and has a slightly everted lip. The throat of the shell is darker. The shell is plump with 4-5 whorls and deep sutures.
Original Distribution: Littorina saxatilis has a wide
dispersal in the
Current Distribution: Littorina saxatilis is currently
invasive in the
Mode(s) of Introduction: There is no certainty of mode of introduction. However, it is the general concensus that the invasion was likely due to the association with bait or live seafood transport. They have been associated with an Atlantic alga (Ascophyllum nodosum), which is often used as packing material for shipments of live animals.
Reason(s) Why it has Become Established: Littorina saxatilis is successful in becoming established in a previously foreign area in that it has a capacity to feed on newly settled barnacles and can compete successfully with other like organisms for food supplies. The study described below intends to pursue further research on successful invasion of this species.
Threat(s): Observations of the behavior of Littorina saxatilis in the
Control Level Diagnosis: Some experts believe that the rough periwinkle should be easily eradicated. For one thing, it does not possess a larval stage of development which would increase its chances of spreading via a “free floating state” to other areas. So far, its invasive range is believed to be restricted to areas within the
Control Method: No method is yet forthcoming for the removal of this specific species. In general, biocides, manual removal of marine invaders, and the introduction of biocontrol agents have been considered in the removal of invaders of marine systems. However, little has been done in the way of eradication and, in addition, pursuing research in this area in general. There is concern that any research to be conducted should include the study of ways to avoid reintroduction of the species. A study sponsored by NOAA and the
Author: Debbie Graham
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