Chesapeake Bay Introduced Species Database


Myosotella myosotis

Common name(s):
salt marsh snail
Myosotella myosotis is a small brown salt marsh snail, native to Europe (British Isles, Mediterranean, etc.), that is sometimes called the mouse-ear marsh snail. It has been introduced into several locations including the East Coast of North America from Nova Scotia to the West Indies, the US west coast from Washington to California, South Africa, Australia, and New Zealand. Introduction of this snail could have occurred by several means including, dry ballast (rocks and dirt used for weight on old sailing vessels), the oyster trade, and discarded packing material. Once these snails have been introduced to a new location their local range expansion is limited, thus their distribution remains spotty for years after introduction. These snails were first reported in Chesapeake Bay in 1900 in St. Leonard?s Creek, a Patuxent River tributary. But over the years they have shown up in several other locations including Fisherman's Island (Northampton Co), VA, at the mouth of the Bay, Norfolk, VA marshes, Crisfield, MD, and the Little Annemessex River in Maryland. Along the Atlantic Coast they have been reported in Chincoteague, Watt's Bay, Willis Wharf, and Hog Island Bay, VA. No negative impacts have been reported.
Image courtesy of Auguste Le Roux.

Economic Impacts

Impact:
The salt marsh snail Myosotella myosotis has no known economic impacts in Chesapeake Bay.


Economic Impacts Outside Chesapeake Bay

Impact:
The salt marsh snail Myosotella myosotis has no economic impacts in its native or introduced range.


Ecological Impacts

Impacts on Natives:
The salt marsh snail Myosotella myosotis is very local in its distribution and seems to coexist well with two other species of similar habits, Melampus bidentatus (native) and Assiminea succinea (cryptogenic) (Allen 1954a; Wass 1972). Of these three upper intertidal, semiterrestrial snails, Melampus bidentatus appears to be by far the most abundant on the Atlantic Coast and Chesapeake Bay (Gosner 1978; Wass 1972). Carlton and Berman (1991) found that no feeding interactions occurred between M. myosotis, and the native snails Assiminea californica; and Littorina subrotundata in California salt marshes.

References - Allen 1954a; Berman and Carlton 1991; Gosner 1978; Wass et. al. 1972
Impacts on Non-natives:
Myosotella myosotis frequently co-occurs with Assiminea succinea (cryptogenic) (Allen 1954a; Wass 1972). Berman and Carlton (1991) found that no feeding interactions occurred between M. myosotis, Assiminea californica, and Littorina subrotundata in California salt marshes.

References - Allen 1954a; Berman and Carlton 1991; Gosner 1978; Wass et. al 1972


This data was last modified on Wednesday, September 21st, 2005.
Databases Overview| Chesapeake Bay |