Styela plicata is a tropical to temperate tunicate

Tunicate

Tunicates, also known as urochordates, are members of the subphylum Tunicata, previously known as Urochordata, a group of underwater saclike filter feeders with incurrent and excurrent siphons that is classified within the phylum Chordata. While most tunicates live on the ocean floor, others such...

 that has invaded the Gulf of Mexico

Gulf of Mexico

The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...

 by hitching a ride on ships' hulls. This sessile filter feeder can expel water when threatened, leading to the name “sea squirt.” This species is rather hardy; “able to tolerate changes in seawater between 10°-30°C and salinites between 22%-34%” (Thiyagarajan & Qian, 2003) as well as pollution and brackish water. This species is difficult to manage because of the large amount of fluctuation in its population; a colony may be large one year and absent the next. Preventative measures include anti-fouling paints, wood preservation, and slime control containing tributyltin

Tributyltin

Tributyltin compounds are a group of compounds containing the 3Sn moiety, such as tributyltin hydride or tributyltin oxide. They are the main active ingredients in certain biocides used to control a broad spectrum of organisms...

.