What you'll find at this site: Some Background . . . What Sort of Animal is a Tunicate? Invasive Marine Species - how are they getting here, and why are we concerned? Links to more information on invaders of Puget Sound and other marine coastlines. Some Activities . . . Experiments with Marine Settlers - how you can catch and observe native and non-native settlers. Measuring and Recording - how to measure dock colonizing populations. Catalog of Dock Fouling Species - Send us your photos to help it grow. For teachers and parents. . . Logistics and safety considerations Exotic tunicate activities, science inquiry skills, and the National Science Education Standards

Exotic Tunicates on the Move . . . a summer marine biology investigation for middle or high school students of Puget Sound   Introduced species are attracting lots of attention in the media these days. Marine invaders of our coastlines are especially troubling, because they are nearly impossibly to eradicate once they become established. Many scientists are working hard to keep up with the rate that invasive species are now showing up on our shores. They are trying to answer questions such as: What new species have appeared in our area? How extensively they have established themselves? What impacts they are having on native species whose habitats they have invaded?

Students in the Puget Sound region have a chance to witness and help document the invasion of a newly arrived marine organism that attaches to docks and boat hulls. How it will affect the marine environment will take some time to assess, but one thing is clear already. This species should be easy to spot as it moves into new parts of Puget Sound, and it may in fact become a dominant organism in parts of its new environment.

The invader is Ciona savignyi (pronounced Sióna savíni), a tunicate, an interesting invertebrate animal closely related to vertebrates like ourselves. Although Puget Sound is home to many native tunicate species, this one is native to Japan. Ciona savignyi was probably brought into Puget Sound by trans-oceanic shipping, perhaps in ballast water carried inside ships, or as adult animals attached to ships' hulls.

Ciona savignyi attached to mussel shells.