Abalone

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For other uses, see Abalone (disambiguation).

{{Taxobox | color = pink | name = Abalone | image = AbaloneOutside.jpg | regnum = Animalia | phylum = Mollusca | classis = Gastropoda | ordo = Archaeogastropoda | superfamily = Pleurotomariacea | familia = Haliotidae | familia_authority = Rafinesque, 1815 | genus = Haliotis | genus_authority = Linnaeus, 1758 | subdivision_ranks = Species | subdivision = Many: see text. }}

Image:Abalone.jpg Image:AbaloneInside.jpg Image:AbaloneMeat.jpg

Abalone is the American English variant of the Spanish name Abulón used for various species of shellfish (mollusks) from the Haliotidae family (genus Haliotis). The abalones belong to the large class of gastropods (Gastropoda). There is only one genus in the family Haliotidae, and about four to seven subgenera. The taxonomy is somewhat confused. The number of species range from about 100 to about 130 species (due to the occurrence of hybrids), characterized by a richly coloured (on the inside—the outside is rough and mostly brown) shell yielding mother-of-pearl. This is also commonly called ear-shell, in Guernsey ormer (Fr. ormier, for oreille de mer), perlemoen in South Africa and pāua in New Zealand. Abalone is also prevalent in Australian and South African coastal waters and is highly valued. The muscle tissue of this mollusk is considered a delicacy in certain parts of South-East and East Asia, especially in China and Japan.

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Distribution and characteristics

The Haliotid family has a worldwide distribution, along the coastal waters of every continent, except South America and the East Coast of the United States. Most abalones are found off the Southern Hemisphere coasts of New Zealand, South Africa and Australia, and Western North America and Japan in the Northern Hemisphere.

The family has unmistakable characteristics : the shell is rounded to oval, with two to three whorls, and the last one auriform, grown into a large "ear", giving rise to the common name ‘ear-shell’. The body whorl has a series of holes — four to ten depending on the species, near the anterior margin.

There is no operculum. The back is convex, ranging from highly arched to very flattened. These shells cling solidly with their muscular foot to rocky surfaces at sublittoral depths. The color is very variable from species to species. The inside of the shell consists of iridiscent, silvery white to greenred mother-of-pearl through to Haliotis Iris which can comprise of; pinks and reds with predominant deep blues, greens and purples.

Abalones reach maturity at a small size. Their fertility is high and increases with size (from 10,000 to 11 million eggs at a time).

The larvae feed on plankton. The adults are herbivores and feed on macroalgae, preferring red algae. Sizes vary from 20 mm (Haliotis pulcherrima) to 200 mm (or even more) (Haliotis rufescens).

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Abalone diving in California

Sport harvesting of Red Abalone is permitted with a California fishing license and an abalone stamp card. Abalone may only be taken using breath-hold techniques: freediving or shorepicking. SCUBA diving for abalone is strictly prohibited. Taking of abalone is not permited south of the mouth of the San Francisco Bay. There is a size minimum of seven inches measured across the shell and a quantity limit of three per day and 24 per year. Abalone may only be taken in April, May, June, August, September, October and November; abalone may not be taken in July, December, January, February or March. Transportation of abalone may only legally occur while the abalone is still attached in the shell. Sale of sport obtained abalone is illegal, including the shell. Only Red Abalone may be taken; black, white, pink, and flat abalone are protected by law.

An abalone diver is normally equipped with a very thick wetsuit, including a hood, booties, and gloves. He or she would also wear a mask, snorkel, weight belt, abalone iron, and abalone gauge. It is common to take abalone in water a few inches up to 10m/28' deep; less common are freedivers who can work deeper than 10m/28'. Abalone are normally found on rocks near food sources (kelp). An abalone iron is used to pry the abalone from the rock before it can fully clamp down. Visibility is normally five to ten feet. Divers commonly dive out of boats, kayaks, tube floats, and directly off shore. An eight inch abalone is considered a good catch, nine inches extremely good, and a ten inch plus (250 mm) abalone would be a trophy catch. Rock- or shore-picking is a separate method from diving where the rock picker feels underneath rocks at low tides for abalone.

There has been a trade in diving to catch abalones off parts of the United States coast from before 1939. In World War II, many of these abalone divers were recruited into the United States armed forces and trained as frogmen.

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Abalone diving in New Zealand

Image:Abalone-farm1web.jpg

There is an extensive global black market in the collection and export of abalone meat. In New Zealand, where abalone is called pāua in the Māori language, this can be a particularly awkward problem where the right to harvest pāua can be granted legally under Māori customary rights. When such permits to harvest are abused, it is frequently difficult to police. The legal recreational daily limit is 10 pāua per diver with a minimum shell length of 125 mm. The limit is strictly enforced by roving Ministry of Fisheries officers with the backing of the Police force. Pāua 'poaching' is a major industry in New Zealand with many thousands being taken illegally, often undersized. Convictions have resulted in seizure of diving gear, boats and motor vehicles as well as fines and in rare cases; imprisonment. The Ministry of Fisheries expects in the year 2004/05, nearly 1000 tons of pāua will be poached, with 75% of that being undersized.[1]

Highly polished New Zealand pāua shells are extremely popular as souvenirs with their striking blue, green and purple iridescence. Transporting unprocessed abalone shells out of New Zealand is illegal.

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Ormers in the Channel Islands

Ormers (Haliotis tuberculata) are considered a delicacy in the Channel Islands and are pursued with great alacrity by the locals. Unfortunately, this has led to a dramatic depletion in numbers since the latter half of the 19th century, and 'ormering' is now strictly regulated in order to preserve stocks. The gathering of ormers is now restricted to a number of 'ormering tides', from the January 1 to April 30, which occur on the full or new moon and two days following. No ormers may be taken from the beach that are under 8 cm in shell length. Diving is strictly prohibited. Any breach of these laws is a criminal offence and can lead to a heavy fine. The demand for ormers is such that they led to the world's first underwater arrest, when a Mr Kempthorne-Leigh of Guernsey was arrested by a police officer in full diving gear when illegally diving for ormers.

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Abalone shell

In addition, material scientists at the University of California, San Diego are studying abalone's strong calcium carbonate tiled structure for insight into a new generation of bullet-proof body armor.

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List of species with common name

Image:Pinkabalone 300.jpg

Image:Whiteabalone 300.jpg

Other species : Haliotis clathrata, Haliotis barbouri, Haliotis crebrisculpta, Haliotis dissona, Haliotis exigua, Haliotis fatui, Haliotis kamtschatkana assimilis, Haliotis kamtschatkana kamtschatkana, Haliotis madaka, Haliotis mariae, Haliotis patamakanthini, Haliotis pustulata, Haliotis roberti, Haliotis rubiginosa, Haliotis rubra, Haliotis rugosa, Haliotis thailandis, Haliotis unilateralis.

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Research

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External links

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ja:アワビ sk:Haliotis tr:Denizkulağı (Hayvan) uk:Абалон zh:鮑魚

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