MARINE FOULING ORGANISMS

 Photography by Dann Blackwood, US Geological Survey, 2008.  Tunicate information made available by Mary Carman. 

Photography by Dann Blackwood, US Geological Survey, 2008.  Tunicate information made available by Mary Carman. 

So what is a tunicate?

Tunicates are not the most well-known marine animal and yet non-native tunicate species can be disruptive to ecosystem structure and function.  The tunicate lifestyle resembles that of a plant, in that they attach and grow on submersed surfaces. Tunicates range in color from bright orange and yellow to purple and brown.  They are invertebrates, animals without backbones, and grow in one of two shapes: as a solitary vase form, with two openings called siphons on the top of their rounded body or flat and encrusting, over-growing surfaces to which they attach.

Non-native tunicate introductions tend to quickly populate and overgrow surfaces, fouling almost anything submersed including algae, shellfish, rocks, chains and mooring lines. They are easy to find on docks, ship hulls, buoys and aquaculture structures. We would like to monitor their presence in an effort to control their effects. Detection and location of the following tunicates would be helpful to know.

What should you do if you think you have detected a non-native tunicate? Do not disturb it.

Note the location, size and what it is growing on ideally by taking a cell phone photo.

Upload to the Nantucket Fouling Marine Organisms project on iNaturalist.com or forward photos to the NATs Committee.