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74-450: Haliotis , common name abalone , is the only genus in the family Haliotidae. This genus once contained six subgenera. These subgenera have become alternate representations of Haliotis . The genus consists of small to very large, edible, herbivorous sea snails , marine gastropod molluscs . The number of species recognized worldwide ranges between 30 and 130, with over 230 species-level taxa described. The most comprehensive treatment of

148-462: A few inches up to 10 m (33 ft); less common are freedivers who can work deeper than 10 m (33 ft). Abalone are normally found on rocks near food sources such as kelp . An abalone iron is used to pry the abalone from the rock before it has time to fully clamp down. Divers dive from boats, kayaks, tube floats, or directly off the shore. The largest abalone recorded in California

222-537: A millennium earlier in the Morro Bay area. The subspecies Haliotis cracherodii californiensis is found around Guadalupe Island , off Baja California ( Mexico ). Black abalones cling to rocky surfaces in the low intertidal zone, up to 6 m deep. They can typically be found wedged into crevices, cracks, and holes during low tide . They generally occur in areas of moderate to high surf. Juveniles tend to reside in crevices to reduce their risk of predation, but

296-599: 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. Abalones are one of the many classes of organism threatened with extinction due to overfishing and the acidification of oceans from recent higher levels of carbon dioxide , as reduced pH erodes their shells. In

370-570: A permit provided catch limits, size restrictions, and seasonal and local restrictions set by the Ministry for Primary Industries (MPI) are followed. The legal recreational daily limit is 10 per diver, with a minimum shell length of 125 mm (4.9 in) for H. iris and 80 mm (3.1 in) for H. australis . In addition, no person may be in possession, even on land, of more than 20 pāua or more than 2.5 kg (5.5 lb) of pāua meat at any one time. Pāua can only be caught by free-diving; it

444-575: A petition to NMFS to list the black abalone. On January 11, 2008, NMFS completed their status review of the species and proposed that it be listed as endangered. Black abalone were listed as endangered on January 14, 2009. The NMFS designated critical habitat for the endangered black abalone on October 27, 2011. The state of California has introduced an Abalone Recovery Management Plan to guide conservation efforts. Black abalone have dramatically declined in numbers throughout their historical range, and are locally extirpated in certain areas. This decline

518-519: A relatively smooth dark shell. This used to be the most abundant large marine mollusk on the west coast of North America , but now, because of overfishing and the withering syndrome , it has much declined in population and the IUCN Red List has classed the black abalone as Critically Endangered . Haliotis cracherodii comprises two subspecies : The coloration is dark brown, dark green, dark blue or almost black. The silvery interior of

592-441: A row near the shell's outer edge. The thick inner layer of the shell is composed of nacre , which in many species of abalone is highly iridescent, giving rise to a range of strong, changeable colors, which make the shells attractive to humans as decorative objects, in jewelry, and as a source of colorful mother-of-pearl. The shell of abalones is convex , rounded to oval shape, and may be highly arched or very flattened. The shell of

666-483: A set of 24 tags. This was reduced to 18 abalone per year in 2014, and as of 2017 the limit has been reduced to 12, only nine of which may be taken south of Mendocino County . Legal-size abalone must be tagged immediately. Abalone may only be taken using breath-hold techniques or shorepicking; scuba diving for abalone is strictly prohibited. Taking of abalone is not permitted south of the mouth of San Francisco Bay . A size minimum of 7 in (180 mm) measured across

740-635: A shell and settle onto a rock. Juveniles do not tend to disperse great distances, and current populations of black abalone are generally composed of individuals that were spawned locally. Juveniles settle in crevices and remain hidden until they reach approximately 4 inches in length. At that point, adults congregate in more exposed areas such as rocks and in tide pools. They are thought to be able to live for between 25 and 75 years, and will begin to reproduce between three and seven years. Black abalones are herbivorous gastropods, and feed mostly on drift algae and kelp . Their primary food species depend on

814-411: A significant decline in catches, with the total allowable catch reduced from 1440 to 787 tonnes for the 2011/12 fishing year , due to dwindling stocks and most notably the abalone virus ganglioneuritis , which is fast-spreading and lethal to abalone stocks. Sport harvesting of red abalone is permitted with a California fishing license and an abalone stamp card. In 2008, the abalone card also came with

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888-476: A source of colorful mother-of-pearl . The flesh of abalones is widely considered to be a delicacy , and is consumed raw or cooked by a variety of cuisines . Most abalone vary in size from 20 mm (0.8 in) ( Haliotis pulcherrima ) to 200 mm (8 in). The largest species, Haliotis rufescens , reaches 300 mm (12 in). The shell of abalones is convex , rounded to oval in shape, and may be highly arched or very flattened. The shell of

962-423: A whole are considered highly vulnerable to ocean acidification due to their accretion of aragonite and dependence on susceptible coralline algae for development, and thus may eventually go extinct unless the rate of ocean acidification is arrested. Abalone Abalone ( / ˈ æ b ə l oʊ n i / or / ˌ æ b ə ˈ l oʊ n i / ; via Spanish abulón , from Rumsen aulón )

1036-399: Is imperforate , shows an exserted spire, and has prickly ribs. A mantle cleft in the shell impresses a groove in the shell, in which are the row of holes (known as tremata), characteristic of the genus. These holes are respiratory apertures for venting water from the gills and for releasing sperm and eggs into the water column. They make up what is known as the selenizone which forms as

1110-431: Is imperforate , shows an exserted spire, and has prickly ribs. A mantle cleft in the shell impresses a groove in the shell, in which are the row of holes characteristic of the genus. These holes are respiratory apertures for venting water from the gills and for releasing sperm and eggs into the water column. They make up what is known as the selenizone , which forms as the shell grows. This series of eight to 38 holes

1184-577: Is 12.34 in (31.3 cm), caught by John Pepper somewhere off the coast of San Mateo County in September 1993. The mollusc Concholepas concholepas is often sold in the United States under the name "Chilean abalone", though it is not an abalone, but a muricid . In New Zealand, abalone is called pāua ( / ˈ p aʊ ə / , from the Māori language ). Haliotis iris (or blackfoot pāua)

1258-748: Is a common name for any small to very large marine gastropod mollusc in the family Haliotidae , which once contained six genera but now contains only one genus, Haliotis . Other common names are ear shells , sea ears , and, now rarely, muttonfish or muttonshells in parts of Australia , ormer in the United Kingdom , perlemoen in South Africa , and pāua in New Zealand . The number of abalone species recognized worldwide ranges between 30 and 130 with over 230 species-level taxa described. The most comprehensive treatment of

1332-636: 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. 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. See article Najeonchilgi regarding Korean handicraft. Abalone has been an important staple in

1406-410: Is an animal that is declining in numbers, and will need protection throughout the globe. Haliotis cracherodii Haliotis cracherodii , the black abalone , is a species of large edible sea snail , a marine gastropod mollusk in the family Haliotidae , the abalones. This species is relatively small compared with most of the other abalone species from the eastern Pacific , and it has

1480-717: Is declining in numbers, and will need protection throughout the globe. Over half of the modern Haliotis species with sufficient data are considered threatened to some extent on the IUCN Red List , with all but one species from the Pacific coast of North America being critically endangered as a consequence of massive historical overharvesting , withering abalone syndrome , and recent marine heatwaves which have caused collapses of both abalones and their habitat. Haliotis species from elsewhere are also threatened by overexploitation and climate change. In addition, abalones as

1554-432: Is illegal to catch them using scuba gear. An extensive global black market exists in collecting and exporting abalone meat. 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 limit is strictly enforced by roving Ministry for Primary Industries fishery officers with

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1628-457: Is near the anterior margin. Only a small number is generally open. The older holes are gradually sealed up as the shell grows and new holes form. Each species has a typical number of open holes, between four and 10, in the selenizone. An abalone has no operculum . The aperture of the shell is very wide and nacreous . The exterior of the shell is striated and dull. The color of the shell is very variable from species to species, which may reflect

1702-621: Is prohibited for sale in the country to help reduce poaching; however, much of the illegally harvested meat is sold in Asian countries. As of early 2008, the wholesale price for abalone meat was approximately US$ 40.00 per kilogram. There is an active trade in the shells, which sell for more than US$ 1,400 per tonne . Ormers ( Haliotis tuberculata ) are considered a delicacy in the British Channel Islands as well as in adjacent areas of France, and are pursued with great alacrity by

1776-421: Is the largest of the genus at 30 cm (12 in). By weight, about one-third of the animal is edible meat, one-third is offal , and one-third is shell. The shell of the abalone is exceptionally strong and is made of microscopic calcium carbonate tiles stacked like bricks. Between the layers of tiles is a clingy protein substance. When the abalone shell is struck, the tiles slide instead of shattering and

1850-638: Is the ubiquitous New Zealand pāua, the highly polished nacre of which is extremely popular as souvenirs with its striking blue, green, and purple iridescence. Haliotis australis and Haliotis virginea are also found in New Zealand waters, but are less popular than H. iris . Haliotis pirimoana is a small species endemic to Manawatāwhi / the Three Kings Islands that superficially resembles H. virginea . Like all New Zealand shellfish, recreational harvesting of pāua does not require

1924-575: Is very large. The radula has small median teeth, and the lateral teeth are single and beam-like. About 70 uncini are present, with denticulated hooks, the first four very large. The soft body is coiled around the columellar muscle , and its insertion, instead of being on the columella, is on the middle of the inner wall of the shell. The gills are symmetrical and both well developed. These snails cling solidly with their broad muscular foot to rocky surfaces at sublittoral depths, although some species such as Haliotis cracherodii used to be common in

1998-564: The California Fish and Game Commission closed recreational abalone season due to dramatically declining populations. That year, they extended the moratorium to last through April 2021. An abalone diver is normally equipped with a thick wetsuit , including a hood, bootees , and gloves, and usually also a mask, snorkel , weight belt , abalone iron, and abalone gauge. Alternatively, the rock picker can feel underneath rocks at low tides for abalone. Abalone are mostly taken in depths from

2072-406: The Pacific coast of the United States from Mendocino County, California to Cabo San Lucas , Baja California , Mexico. Prehistoric distribution has been confirmed along much of this range from archaeological recovery at a variety of Pacific coastal Native American sites. For example, Chumash peoples in central California were known to have been harvesting black abalone approximately

2146-587: The intertidal zone . Abalones reach maturity at a relatively small size. Their fecundity is high and increases with their size (from 10,000 to 11 million eggs at a time). The spermatozoa are filiform and pointed at one end, and the anterior end is a rounded head. The larvae are lecithotrophic . The adults are herbivorous and feed with their rhipidoglossan radula on macroalgae , preferring red or brown algae. Sizes vary from 20 mm ( 25 ⁄ 32  in) ( Haliotis pulcherrima ) to 200 mm ( 7 + 7 ⁄ 8  in), while Haliotis rufescens

2220-473: The intertidal zone . Abalones reach maturity at a relatively small size. Their fecundity is high and increases with their size, laying from 10,000 to 11 million eggs at a time. The spermatozoa are filiform and pointed at one end, and the anterior end is a rounded head. The haliotid family has a worldwide distribution, along the coastal waters of every continent, except the Pacific coast of South America,

2294-602: The 1850s to about 1900. Black abalone are listed on the International Union for Conservation of Nature 's Red List as Critically Endangered (CR A4e). On June 23, 1999, the U.S. National Marine Fisheries Service (NMFS) designated the black abalone as a candidate for protection under the Endangered Species Act (64 FR 33466). On December 21, 2006, the Center for Biological Diversity submitted

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2368-501: 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. The number of species that are recognized within

2442-523: The Atlantic coast of North America, the Arctic , and Antarctica . The majority of abalone species are found in cold waters, such as off the coasts of New Zealand, South Africa, Australia, Western North America, and Japan. The shell of the abalone is exceptionally strong and is made of microscopic calcium carbonate tiles stacked like bricks. Between the layers of tiles is a clingy protein substance. When

2516-560: The California sheephead, Semicossyphus pulcher ) and invertebrates , including crustaceans such as the striped shore crab, Pachygrapsus crassipes , and spiny lobsters . Competition for space with other species (such as the sea urchins Strongylocentrotus purpuratus and Strongylocentrotus franciscanus ) is also frequent. Humans have harvested black abalones along the California Coast for at least 10,000 years. On San Miguel Island, archaeological evidence shows that

2590-576: The Greater China region and among Overseas Chinese communities, abalone is commonly known as bao yu , and sometimes forms part of a Chinese banquet. In the same way as shark fin soup or bird's nest soup , abalone is considered a luxury item , and is traditionally reserved for celebrations. As abalone became more popular and less common, the prices adjusted accordingly. In the 1920s, a restaurant-served portion of abalone, about 4 ounces, would cost (in inflation adjusted dollars) about US$ 7; by 2004,

2664-564: The Island Chumash people and their ancestors ate black abalone for millennia and also used the shells to make fishhooks, beads, and ornaments. After the Chumash and other California Indians were devastated by European diseases, and sea otters were nearly eradicated from California waters by the historic fur trade, black abalone populations rebounded and attracted an intensive intertidal fishery conducted primarily by Chinese immigrants from

2738-631: The Japanese perfected diving, with or without gear, to enter the market. Abalone started to become popular in the US after the Panama–Pacific International Exposition in 1915, which exhibited 365 varieties of fish with cooking demonstrations, and a 1,300-seat dining hall. In Japan, live and raw abalones are used in awabi sushi, or served steamed, salted, boiled, chopped, or simmered in soy sauce . Salted, fermented abalone entrails are

2812-584: The South African government listed abalone as an endangered species according to the CITES section III appendix, which requests member governments to monitor the trade in this species. This listing was removed from CITES in June 2010 by the South African government and South African abalone is no longer subject to CITES trade controls. Export permits are still required, however. The abalone meat from South Africa

2886-459: The United States. After trials in 2012, a commercial "sea ranch" was set up in Flinders Bay , Western Australia to raise abalone. The ranch is based on an artificial reef made up of 5,000 separate concrete abalone habitat units, which can host 400 abalone each. The reef is seeded with young abalone from an onshore hatchery. The abalone feed on seaweed that grows naturally on the habitats;

2960-670: The abalone shell is struck, the tiles slide instead of shattering and the protein stretches to absorb the energy of the blow. Material scientists around the world are studying this tiled structure for insight into stronger ceramic products such as body armor . The dust created by grinding and cutting abalone shell is dangerous; appropriate safeguards must be taken to protect people from inhaling these particles. Abalones are subject to various diseases. The Victorian Department of Primary Industries said in 2007 that ganglioneuritis killed up to 90% of stock in affected regions. Abalone are also severe hemophiliacs , as their fluids will not clot in

3034-404: The animal's diet. The iridescent nacre that lines the inside of the shell varies in color from silvery white, to pink, red and green-red to deep blue, green to purple. The animal has fimbriated head lobes and side lobes that are fimbriated and cirrated . The radula has small median teeth, and the lateral teeth are single and beam-like. They have about 70 uncini , with denticulated hooks,

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3108-618: The backing of the New Zealand Police. 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 and fines and in rare cases, imprisonment. There are five species endemic to South Africa, namely H. parva , H. spadicea , H. queketti and H. speciosa . The largest abalone in South Africa, Haliotis midae , occurs along roughly two-thirds of

3182-497: The black abalone. The depleted stocks of black abalone were further reduced by withering syndrome , first discovered in 1985, when commercial fishermen reported large numbers of empty shells and dying abalones on the shores of several of the Californian Channel Islands (including the islands of Santa Cruz , Anacapa , Santa Rosa , Santa Barbara , San Miguel , and San Clemente ). This disease impairs

3256-485: The case of a laceration or puncture wound. Members of the Spionidae of the polychaetes are known as pests of abalone. Abalone has been harvested worldwide for centuries as a source of food and decorative items. Abalone shells and associated materials, like their claw-like pearls and nacre , have been used as jewelry and for buttons, buckles, and inlay. These shells have been found in archaeological sites around

3330-539: The country's coastline. Abalone-diving has been a recreational activity for many years, but stocks are currently being threatened by illegal commercial harvesting . In South Africa, all persons harvesting this shellfish need permits that are issued annually, and no abalone may be harvested using scuba gear. For the last few years, however, no permits have been issued for collecting abalone, but commercial harvesting still continues as does illegal collection by syndicates . In 2007, because of widespread poaching of abalone,

3404-462: The diver is working. Bags of abalone pried from the rocks are brought to the surface by the diver or by way of "shot line", where the deckhand drops a weighted rope for the catch bag to be connected then retrieved. Divers measure each abalone before removing from the reef and the deckhand remeasures each abalone and removes excess weed growth from the shell. Since 2002, the Victorian industry has seen

3478-481: The ecosystem enrichment of the bay also results in growing numbers of dhufish , pink snapper , wrasse , and Samson fish among other species. Abalones have long been a valuable food source for humans in every area of the world where a species is abundant. The meat of this mollusc is considered a delicacy in certain parts of Latin America (particularly Chile), France, New Zealand, East Asia and Southeast Asia. In

3552-462: The family considers 56 species valid, with 18 additional subspecies . The shells of abalones have a low, open spiral structure, and are characterized by several open respiratory pores in a row near the shell's outer edge. The thick inner layer of the shell is composed of nacre , which in many species is highly iridescent , giving rise to a range of strong, changeable colors which make the shells attractive to humans as ornaments , jewelry , and as

3626-481: The family considers 56 species valid, with 18 additional subspecies. Other common names are ear shells , sea ears , and, rarely, muttonfish or muttonshells in parts of Australia, ormer in the UK , perlemoen in South Africa , and the Māori name for three species in New Zealand is pāua . The shells of abalones have a low, open, spiral structure, and are characterized by having several open respiratory pores in

3700-482: The first four very large. The rounded foot is very large in comparison to most molluscs. The soft body is coiled around the columellar muscle , and its insertion, instead of being on the columella, is on the middle of the inner wall of the shell. The gills are symmetrical and both well developed. These snails cling solidly with their broad, muscular foot to rocky surfaces at sublittoral depths, although some species such as Haliotis cracherodii used to be common in

3774-456: 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

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3848-409: The genus Haliotis has fluctuated over time, and depends on the source that is consulted. The number of recognized species ranges 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 evaluated for conservation status. Those that have been reviewed tend to show that the abalone in general

3922-410: The habitat. In southern California habitats, black abalones are thought to feed on the giant kelp ( Macrocystis pyrifera ) and feather boa kelp ( Egregia menziesii ), while in central and northern California habitats they feed on the bull kelp ( Nereocystis leutkeana ). Predators of this species other than mankind are sea otters (such as the southern sea otter, Enhydra lutris ), fish (such as

3996-667: The harvesting areas and supported larger harvests per unit effort were not initiated. Now, all abalone fisheries in California are managed by the California Department of Fish and Game , which restricts the size of abalones caught, and the season in which harvesting can take place. In Mexico, there is a total allowable catch limit for black abalones. Even though harvesting black abalone is regulated in California, poaching still occurs. Other threats include coastal development for residential areas, harbours and waste discharges, compounded by commercial and recreational fishing of

4070-535: The larger adults will move out onto rock surfaces. Black abalone reach sexual maturity at 3 years and can live 30 years or more. Spawning occurs in spring and early summer; occasionally, a second spawn occurs in the fall. Black abalone are broadcast spawners, and successful spawning requires that individuals be grouped closely together. Larvae are free-swimming for between 5 and 14 days before they settle onto hard substrate, usually near larger individuals, where they then metamorphose into their adult form, develop

4144-426: The late 1950s. The state is sectioned into three fishing zones, Eastern, Central and Western, with each fisher required a zone-allocated licence. Harvesting is performed by divers using surface-supplied air "hookah" systems operating from runabout-style, outboard-powered boats. While the diver seeks out colonies of abalone amongst the reef beds, the deckhand operates the boat, known as working "live" and stays above where

4218-570: The locals. This, and a recent lethal bacterial disease, has led to a dramatic depletion in numbers since the latter half of the 19th century, and "ormering" is now strictly regulated to preserve stocks. The gathering of ormers is now restricted to a number of 'ormering tides', from 1 January to 30 April, which occur on the full or new moon and two days following. No ormers may be taken from the beach that are under 80 millimetres (3.1 in) in shell length. Gatherers are not allowed to wear wetsuits or even put their heads underwater. Any breach of these laws

4292-477: The main component of tottsuru , a local dish from Honshū. Tottsuru is mainly enjoyed with sake. In South Korea, abalone is called Jeonbok (/juhn-bok/) and used in various recipes. Jeonbok porridge and pan-fried abalone steak with butter are popular but also commonly used in soups or ramyeon. In California, abalone meat can be found on pizza, sautéed with caramelized mango, or in steak form dusted with cracker meal and flour. Tasmania supplies about 25% of

4366-402: The majority of species has a small, flat spire and two to three whorls . The last whorl, known as the body whorl , is auriform , meaning that the shell resembles an ear, giving rise to the common name "ear shell". Haliotis asinina has a somewhat different shape, as it is more elongated and distended. The shell of Haliotis cracherodii cracherodii is also unusual as it has an ovate form,

4440-424: The majority of species is ear-shaped, presenting a small, flat spire and two to three whorls . The last whorl, known as the body whorl , is auriform , meaning that the shell resembles an ear, giving rise to the common name "ear shell". Haliotis asinina has a somewhat different shape, as it is more elongated and distended. The shell of Haliotis cracherodii cracherodii is also unusual as it has an ovate form,

4514-554: The mid-1990s, there have been many increasingly successful endeavors to commercially farm abalone for the purpose of consumption. Overfishing and poaching have reduced wild populations to such an extent that farmed abalone now supplies most of the abalone meat consumed. The principal abalone farming regions are China, Taiwan, Japan, and Korea. Abalone is also farmed in Australia, Canada, Chile, France, Iceland , Ireland, Mexico, Namibia , New Zealand, South Africa, Spain, Thailand, and

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4588-458: The north of the state where the minimum size is 132 millimetres (5.2 in). With a recreational abalone licence, the bag limit is 10 per day, with a total possession limit of 20. Scuba diving for abalone is allowed, and has a rich history in Australia. (Scuba diving for abalone in the states of New South Wales and Western Australia is illegal; a free-diving catch limit of two is allowed). Victoria has had an active abalone fishery since

4662-459: The price had risen to US$ 75. In the United States, prior to this time, abalone was predominantly eaten, gathered, and prepared by Chinese immigrants. Before that, abalone were collected to be eaten, and used for other purposes by Native American tribes. By 1900, laws were passed in California to outlaw the taking of abalone above the intertidal zone . This forced the Chinese out of the market and

4736-601: The production of digestive enzymes, effectively starving the abalone to death. Following onset of symptoms, the animal usually quickly dies. In many locations, percentages greater than 90% of individuals have been lost, and in some places, a total loss of the black abalone population occurred. The disease spread from the Channel Islands to the mainland coast in 1992, where it devastated most populations in warmer waters south of Point Conception or in locally warmer waters further north. This article incorporates text from

4810-446: The protein stretches to absorb the energy of the blow. Material scientists around the world are studying this tiled structure for insight into stronger ceramic products such as body armor . The dust created by grinding and cutting abalone shell is dangerous; appropriate safeguards must be taken to protect people from inhaling these particles. There is much discussion of this topic online. The number of species that are recognized within

4884-478: The shell grows. This series of eight to 38 holes is near the anterior margin. Only a small number are generally open. The older holes are gradually sealed up as the shell grows and new holes form. Therefore, the number of tremata is not characteristic for the species. Each species has a number of open holes, between four and 10, in the selenizone. This number is not fixed and can vary within a species and between populations. Abalones have no operculum . The aperture of

4958-452: The shell is in place. A person may be in possession of only three abalone at any given time. As of 2017, abalone season is May to October, excluding July. 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, as black , white , pink , flat , green , and pinto abalone are protected by law. In 2018,

5032-408: The shell is spiralled, and the mantle, foot and tentacles are black. The interior of the shell is pearly with pink and green iridescence. The black abalone's shell length can reach a maximum of 20 cm (7.9 in), being typically 10–14 cm (3.9–5.5 in) long. In the living animal, the tentacles on the epipodium, the mantle, and the foot are black. Black abalones can be found along

5106-453: The shell is very wide and nacreous . The exterior of the shell is striated and dull. The color of the shell is very variable from species to species, which may reflect the animal's diet. The iridescent nacre that lines the inside of the shell varies in color from silvery white, to pink, red and green-red, to deep blue, green to purple. The animal shows fimbriated head-lobes. The side-lobes are also fimbriated and cirrated . The rounded foot

5180-411: The shell shows a pale pinkish and greenish iridescence . The exterior of the shell is smoother than most abalones, or may have low obsolete coarse spiral lirae and lines of growth. The shell is oval, evenly convex, the two sides equally curved. The back of the shell is regularly convex, with little algal growth. The shell is not carinated at the row of holes. The spire is near the margin. The cavity of

5254-449: The spire is minute, concealed or nearly so. The muscle scar is generally not distinct. There are usually five to seven small, open respiratory holes, or pores, along the left side of the shell and the rims of the holes are flush with the rest of the shell. These holes collectively make up what is known as the selenizone which form as the shell grows. The columellar plate is not truncate below, sloping inward, its face concave. The rear of

5328-532: The world, ranging from 100,000-year-old deposits at Blombos Cave in South Africa to historic Chinese abalone middens on California's Northern Channel Islands. For at least 12,000 years, abalones were harvested to such an extent around the Channel Islands that shells in the area decreased in size four thousand years ago. Farming of abalone began in the late 1950s and early 1960s in Japan and China. Since

5402-407: The yearly world abalone harvest. Around 12,500 Tasmanians recreationally fish for blacklip and greenlip abalone. For blacklip abalone, the size limit varies between 138 mm (5.4 in) for the southern end of the state and 127 mm (5.0 in) for the northern end of the state. Greenlip abalones have a minimum size of 145 mm (5.7 in), except for an area around Perkins Bay in

5476-459: Was initiated by overfishing. Following World War II, the California abalone fishery was not managed for individual species. Therefore, it resulted in a systematic depletion of various abalone species as the fishery over-harvested one species and then moved on to the next in an attempt to meet demand. Black abalone were the last to be targeted, with the peak harvest occurring in the 1970s. Additionally, improved harvesting technologies that expanded

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