The Golden Star Tunicate…sounds harmless enough but this is an invasive species that has been found in the Bras d’Or Lakes on eel grass, shellfish and just about anywhere it can attach itself, smothering its host.

144An aquatic invasive species is an organism that has extended its traditional range either naturally, or brought to new areas intentionally or unintentionally.

Invasive species can have significant effects on the ecosystem, both economically and ecologically, by competing with and preying on native fish, invertebrates and plants. Once an aquatic invasive species is established, it is very difficult and costly to control or eliminate.

Tunicates, often called Sea Squirts, are animals with no skeleton. Five types of tunicates can be found along the Atlantic Coast of Canada. Their distribution depends on water temperature and salinity.

In the Bras d’Or Lakes, the Golden Star Tunicate, Botryllus schlosseri, is most common. In the photo on the right, a tunicate has taken over oyster shells.

How are they introduced?

  • Recreational boating
  • Aquarium or water gardens
  • Release of live bait
  • Live food fish trade
  • Aquaculture Man-made canals.

From UINR Marten – Vol.4. Issue.4 – Winter 2008