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Sheath tunicate on rockweed
Credit: A. Pappal
sheath tunicate
Botrylloides violaceus
Characteristics:
Usually orange, sometimes red or dull purple
Individual animals (zooids) arranged in loose circles, rows, or dense colonies
Dense colonies can be extensive, creating firm, gelatinous coating on submerged structures; colony sometimes forms lobes
Habitat:
Grows on rocks, shells, pilings, seaweeds, ship hulls, and other submerged surfaces
Usually below low-tide line
Known Distribution:
Newfoundland to Florida
Native to northwestern Pacific Ocean
Impacts:
Competition with native species (invertebrates and algae) for living space
Grows over other organisms, interfering with their feeding and other behaviors
Common Vector(s):
Shipping: Fouling
Sheath tunicate (Botrylloides violaceus)
Credit: Dann Blackwood (USGS)
Sheath tunicate with other species
Credit: A. Pappal