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Clubbed Tunicate

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Asian tunicate
Asian tunicate - Photo by U.S. Geological Survey
Scientific Name: 
Styela clava Herdman, 1881 (ITIS)
Common Name: 
Clubbed tunicate, stalked sea squirt, solitary sea squirt, leathery sea squirt, Pacific rough sea squirt, Asian sea squirt
Native To: 
Date of U.S. Introduction: 
First observed on the Pacific coast in the 1930s (Clarke and Therriault 2007)
Means of Introduction: 
Probably introduced accidentally on the hulls of ships or with imported oysters (Clarke and Therriault 2007)
Competes with and displaces native species (Clarke and Therriault 2007)
Current U.S. Distribution: 
Coastal regions of New England and the Western U.S.


Selected Resources

The section below contains highly relevant resources for this species, organized by source. Or, to display all related content view all resources for Clubbed Tunicate.

Council or Task Force

Washington State Recreation and Conservation Office. Washington Invasive Species Council.


San Francisco Estuary Institute; Center for Research on Aquatic Bioinvasions.

European Network on Invasive Alien Species.
See also: NOBANIS Fact Sheets for invasive alien species of the European region, covering both animals and plants, as well as microorganisms
IUCN. Species Survival Commission. Invasive Species Specialist Group.
Northeast Aquatic Nuisance Species Panel.
Great Britain Non-Native Species Secretariat.
Federal Government

Smithsonian Institution. Smithsonian Environmental Research Center. Marine Invasions Research Lab.

International Government

National Institute of Water and Atmospheric Research (New Zealand).