Many species of marine fish can at times be plagued by sea lice. Farmed salmon are particularly susceptible to being parasitised by Lepeophtheirus salmonis in the crowded conditions of the cages. To kill the lice the salmon have been exposed to a chemical called 'Nuvan' which is added to the seawater in the cages. However, this chemical is unselective and can kill, or have an adverse impact on crustaceans and a number of other types of marine animals that can be found in the vicinity. Study has shown that Goldsinny are particularly fond of sea lice, and a number of salmon farms are experimenting with these wrasse to see whether this small fish can keep the lice under control. This has meant that these wrasse are caught in increasing numbers and can command a modest price, whereas previously they were thought valueless because they are inedible.