Styela clava is a fast growing, suspension feeder that can reach densities of 500-1,500 individuals per square metre. As a fouling species it can have negative impacts on native and aquaculture species through competition for space and food as well as predation of larvae from the water column (Wood et al., 2018). It can also occur as fouling on vessels, aquaculture and fishing equipment and other artificial structures. Styela clava is a large, club-shaped solitary ascidian with a tough leathery body wall (test), growing up to 160 mm long (Lutzen, 1999). It consists of an elongated, cylindrical body on top of a stalk of variable length. It can be brownish-white, yellowish-brown or reddish-brown. There are two short siphons towards the top of the organism, each with a 4-lobed opening. The body has conspicuous tubercles and rounded swellings on the upper portion and rounded longitudinal ridges on the lower half. The stalk surface is creased. Internally, the gut is a simple U-shaped loop (Clarke and Therriault, 2007).