NAS - Nonindigenous Aquatic Species

small fish


NAS logo - click to go to the NAS home page Mollusks (Phylum Mollusca) are found in marine, brackish, and fresh waters. They include a diverse group of animals such as clams, mussels, oysters, scallops, abalone, conchs, shipworms, snails, nudibranchs, chitons, squids, and octopuses. Common methods of introduction include ballast water introductions, aquarium releases, and accidental release from aquaculture facilities. Displacement by competition is the most frequently observed impact on native species. The most notable nonindigenous mussel introduction is the zebra mussel (Dreissena polymorpha), a native of eastern Europe.
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Data Queries and Species Lists

mudsnail Picture Data Queries
Species List of Nonindigenous Mollusks
(links to factsheets and collection information)
New Zealand Mudsnail Distribution in Google Maps

Zebra and Quagga Mussel Information

zebra mussel picture Zebra and Quagga Mussel Home Page

Links to News and Other Information

Freshwater Mollusk Bibliography (mostly native)
Museum Collections Systematic Research Collections: Mollusca Illinois Natural History Survey
Mollusk Collections UC Berkeley
Invertebrate Zoology Collections at The Smithsonian Institution
University of Michigan Mollusk Division

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