Species Information

Star tunicate
Botryllus schlosseri

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Characteristics

• Individual animals (zooids) live in colonies up to 3-4 in (7.5-10 cm) wide
• Zooids arranged in conspicuous starlike patterns
• Yellow, olive, greenish, tan, brown, purple, or black; individuals outlined in yellow or white
• Colonies begin as soft, flat patches and mature into loose bloblike rolls and lobes

Habitat

• Grows on rocks, shells, seaweeds, pilings, eelgrass, and other solid surfaces
• Along open shores and in brackish estuaries (to 18 ppt or less)
• Near low-tide line and below, to depths of 60 ft (18 m)

Known Distribution in the Northeast

• Newfoundland to Florida
• Native to Europe

Impacts

• Competition with native species (invertebrates and algae) for living space
• Often grows on mussels and oysters, interfering with their feeding and other behaviors food and resources