taken from the beach that are under in shell length. Gatherers are not allowed to wear wetsuits or even put their heads underwater. Any breach of these laws is a criminal offence and can lead to a fine of up to £5,000 or six months in prison. The demand for ormers is such that they led to the world's first underwater arrest, when Mr. Kempthorne-Leigh of Guernsey was arrested by a police officer in full diving gear when illegally diving for ormers. Decorative items The highly iridescent inner nacre layer of the shell of abalone has traditionally been used as a decorative item, in jewelry, buttons, and as inlay in furniture and musical instruments, such as on fret boards and binding of guitars. Indigenous use Abalone has been an important staple in a number of Indigenous cultures around the world, specifically in Africa and on the Northwest American coast. The meat is a traditional food, and the shell is used to make ornaments; historically, the shells were also used as currency in some communities. Threat of extinction Abalones are one of the many classes of organism threatened with extinction due to overfishing and the acidification of oceans from anthropogenic carbon dioxide, as reduced pH erodes their shells. In the 21st century, white, pink, and green abalone are on the United States federal endangered species list, and possible restoration sites have been proposed for the San Clemente Island and Santa Barbara Island areas. The possibility of farming abalone to be reintroduced into the wild has also been proposed, with these abalone having special tags to help track the population. Species The number of species that are recognized within the genus Haliotis has fluctuated over time, and depends on the source that is consulted. The number of recognized species range from 30 to 130. This list finds a compromise using the WoRMS database, plus some species that have been added, for a total of 57. The majority of abalone have not been rated for conservation status. Those that have been reviewed tend to show that the abalone in general is an animal that is declining in numbers, and will need protection throughout the globe. Synonyms See also List of delicacies Citations References Further reading External links Abalone: Species Diversity ABMAP: The Abalone Mapping Project Abalone biology Conchology Hardy's Internet Guide to Marine Gastropods : Shell Catalog book on crafting with Abalone Shell