Aquarium Caulerpa

Caulerpa taxifolia 280px

[Image: Australian Institute of Marine Science]

Caulerpa taxifolia (M.Vahl) C.Agardh, 1817

Status in New Zealand

Not in New Zealand

Legal Status in New Zealand

Unwanted organism


Caulerpa taxifolia is a marine macro-algae that is native to tropical waters of the Indian, Pacific and Atlantic oceans. A variety of C. taxifolia was bred for use in the aquarium trade and it has broader environmental tolerances than plants of the same species in the tropics. The aquarium type has established non-native populations in the Mediterranean, Southern California, USA and temperate areas of Australia. These have initially occurred through the release of aquarium plants either intentionally or accidentally. The Aquarium Caulerpa grows on a variety of substrata, usually between 2-35 metres deep. In the Mediterranean Sea it has been recorded at depths of 100 metres. The Aquarium Caulerpa is spread easily by vegetative growth of small fragments. It can establish in estuaries, harbours and sheltered coastal areas.

Why is it a problem?

The aquarium type is cold-tolerant, fast growing and, in natural environments, can form extensive, dense monoculture beds that occupy all of the available benthic habitat. It reduces the diversity of benthic habitats and species, which have flow-on effects for fishes and other mobile species. The weed is also easily entangled in fishing gear and boat propellers. In the Mediterranean Sea, fish that consume C. taxifolia accumulate toxins in their tissue.

This BBC documentary examines the effects of the aquarium Caulerpa in the Mediterranean and attempts to eradicate it from lagoons in California, USA.

What does it look like?

Key features

Caulerpa taxifolia is bright green. Its fronds are feather-like and flattened with a smooth midrib and branchlets (pinnules) growing equally spaced, either side of the midrib. The fronds grow from a horizontal runner (stolons) that is anchored by root-like structures (rhizoids) to the seafloor. Individual fronds of the aquarium type can be greater than 40 centimetres in length.


 Caulerpa taxifolia Inglis 280 px

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