What are marine invasive tunicates?

In the past few years various species of rapidly reproducing tunicates have become problems at various sites around the world. These species foul all sorts of marine structures and habitats, overgrowing and smothering other organisms on the sea-bed, sometimes covering the siphons of infaunal bivalves, and interfering with aquaculture, fishing, and other activities.

There are three tunicate species currently posing a problem in Washington waters:

• Styela clava or Club tunicate
• Didemnum sp.
• Ciona savignyi

More information on all three of these species can be found here:

http://www.pnwscuba.com/critterwatchers/invasive.htm

Another species, Botrylloides violaceous, is being watched carefully, and you can get more information on how to distinguish it on Don Coleman's Pacific Adventure Charters website:

http://www.pacadventure.com/invasive.htm