| Dredge oyster | |
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| Museum specimen of the shell of Ostrea chilensis | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Bivalvia |
| Order: | Ostreida |
| Family: | Ostreidae |
| Genus: | Ostrea |
| Species: | O. chilensis |
| Binomial name | |
| Ostrea chilensis | |
| Synonyms [1] | |
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The dredge oyster, [2] Bluff oyster [3] or Chilean oyster [4] (Ostrea chilensis), [5] is also known in Chile as ostra verde, [6] is a species of flat oyster. It is a marine bivalve mollusc of the family Ostreidae.
This species is native to Chile and New Zealand. [7]
In Chile, its range limit is from Chiloé Island, Los Lagos region to Guaitecas Islands, Aysén region. [8] Practically, nowadays it only exists in the wild in one natural bank, Pullinque, a sector located in the Quetalmahue Gulf of Ancud which was declared a genetic reserve in 1982, and as a marine reserve in 2003. [9]
In the 1960s, the species was deliberately introduced to the Menai Strait off Wales by the Fisheries Laboratory, Conwy. This was an experiment to determine if the oyster could be an alternative to the native Ostrea edulis oysters in fisheries. The species was found to be unsuitable because of low recruitment and vulnerability to parasites and pathogens, and the experiment was abandoned. A self-sustaining population of O. chilensis remains, and has spread to other areas of the Menai Strait; it is regarded as an invasive species. [10]
This bivalve is found from low tide to depths of up to 35 m. In Chile it lives attached to hard rocky or muddy bottoms, from intertidal to about 8 meters deep, in enclosed bays or areas protected from strong waves. [11]
Its length is up to 105 mm, width up to 70 mm, and inflation up to 33 mm. In Chile its maximum controlled length is 87 mm. [11]
In New Zealand, they are a prized delicacy, and harvested from March to August from the Foveaux Strait oyster fishery, which centres on the town of Bluff (hence the local name). [12] From the early 1980s, the fishery went into serious decline, due to the outbreak of an oyster parasite, Bonamia exitiosa, with the disease killing an estimated billion oysters between 2000 and 2003. [12] The population has been recovering since 2003, with fishermen voluntarily limiting the catch to half the allowable to aid the revival. [12] [13]
In Chile, it has been harvested by the fishermen of Chiloé Island since ancient times, but the written and photographic information dates back to the mid-1800s. [6] As Chile is the longest country in the world, the transportation of the harvested oysters by wooden-made ships, or by early trains in the early 1900s from the south (42°S) to the port of Valparaíso, and then to the capital, Santiago, was complex; however, it got solved when the oysters were placed in barrels that were grated and jointed by quila, a kind of bamboo, and then filled with seawater. [14] The trip lasted half a month. [14] In the city of Ancud, Chiloé Island, the extraction of the oyster was banned even at that time (as in 1869 and then in 1874) due to its overexploitation, on the other hand its sale brought thousands of barrels, boxes and sacks of oysters to the capital to supply its great demand. [6] [14] The oysters was even kept in ponds for growing by Frenchmen, first by Mr. Choloux in Lechagua, Ancud, 1874 and later by the Solminihac family, formally with a concession in Quetalmahue, city of Ancud, in 1915. [6] A couple of years later, in 1935, the Pullinque Oyster Station was built in Pullinque to try to cultivate the Chilean oyster, initiative that proved to be successful because it could provide with seeds for growth to other aquaculture centers that emerged during the agrarian reform period. [6] The economy of Chilean oysters was severely hurt when the most powerful earthquake recorded happened in Valdivia, 1960 because the Pullinque Oyster Station was destroyed by it. [6] Hence, the Corfo institution tried to bring-in the Pacific oyster, but the intention was not recommended by the consulted experts, a decision that was respected by the national government. [6] After the agrarian reform the commercial aquaculture started in the 80s, during the Civic-military dictatorship of Chile, according to FAO, since producers that were state-managed passed to be privately regulated, and also because many exotic species were tentative to introduce as culture options. [15] [6] Nowadays, its culture is successful in Chile with considerable tons exported, and consumed in some places and restaurants.
Changes in river flows in Southland, due to farming and especially power generation, carrying less limestone deposits into the Strait, is therefore believed to have caused an increase in susceptibility to Bonamia, as well as lower growth rates for some seasons in the past,[ citation needed ] but little evidence supports this and it seems only coincidental.[ opinion ]
Flawed discards practices in Chile during the 1890s of the small oysters ended up killing some oyster banks in Ancud. Particularly in Corona lighthouse and Quetalmahue Gulf; as the turbulence generated by the falling oysters resuspended the bottom sand, creating hypoxia conditions that did not allow the bivalves to breathe. [16] [6]
Oyster is the common name for a number of different families of salt-water bivalve molluscs that live in marine or brackish habitats. In some species, the valves are highly calcified, and many are somewhat irregular in shape. Many, but not all oysters, are in the superfamily Ostreoidea.
Chiloé Island also known as Greater Island of Chiloé, is the largest island of the Chiloé Archipelago off the west coast of Chile, in the Pacific Ocean. The island is located in southern Chile, in the Los Lagos Region.
Fishery can mean either the enterprise of raising or harvesting fish and other aquatic life or, more commonly, the site where such enterprise takes place. Commercial fisheries include wild fisheries and fish farms, both in freshwater waterbodies and the oceans. About 500 million people worldwide are economically dependent on fisheries. 171 million tonnes of fish were produced in 2016, but overfishing is an increasing problem, causing declines in some populations.
Foveaux Strait is a strait that separates Stewart Island from the South Island of New Zealand. The width of the strait ranges from about 23 to 53 km, and the depth varies between 18 and 46 m. The strait was first charted by an American sealer, Owen Folger Smith. He charted the strait from a whaleboat of the sealing brig Union in 1804.
A fish hatchery is a place for artificial breeding, hatching, and rearing through the early life stages of animals—finfish and shellfish in particular. Hatcheries produce larval and juvenile fish, shellfish, and crustaceans, primarily to support the aquaculture industry where they are transferred to on-growing systems, such as fish farms, to reach harvest size. Some species that are commonly raised in hatcheries include Pacific oysters, shrimp, Indian prawns, salmon, tilapia and scallops.
The Pacific oyster, Japanese oyster, or Miyagi oyster is an oyster native to the Pacific coast of Asia. It has become an introduced species in North America, Australia, Europe, and New Zealand.
Oyster farming is an aquaculture practice in which oysters are bred and raised mainly for their pearls, shells and inner organ tissue, which is eaten. Oyster farming was practiced by the ancient Romans as early as the 1st century BC on the Italian peninsula and later in Britain for export to Rome. The French oyster industry has relied on aquacultured oysters since the late 18th century.
Saccostrea glomerata is an oyster species belonging to the family Ostreidae.
Ostrea is a genus of edible oysters, marine bivalve mollusks in the family Ostreidae, the oysters.
Ostrea edulis, commonly known as the European flat oyster, is a species of oyster native to Europe. In Great Britain and Ireland, regional names include Colchester native oyster, mud oyster, or edible oyster. In France, Ostrea edulis are known as huîtres plates except for those that come from the Belon River estuary in Brittany, France, which are known as Belons.
The Chiloé Archipelago is a group of islands lying off the coast of Chile, in the Los Lagos Region. It is separated from mainland Chile by the Chacao Channel in the north, the Sea of Chiloé in the east and the Gulf of Corcovado in the southeast. All islands except the Desertores Islands form Chiloé Province. The main island is Chiloé Island. Of roughly rectangular shape, the southwestern half of this island is a wilderness of contiguous forests, wetlands and, in some places, mountains. The landscape of the northeastern sectors of Chiloé Island and the islands to the east is dominated by rolling hills, with a mosaic of pastures, forests and cultivated fields.
Placunidae, also known as windowpane oysters, windowpane shells, and Capiz shells, are a taxonomic family of saltwater clams, marine bivalve mollusks which are related to oysters and scallops.
Enteroctopus megalocyathus, also known as Patagonian red octopus (EN), Pulpo del sur (Chile) and Pulpo colorado (Argentina); is a medium-sized octopus, and the type species for the genus Enteroctopus.
Fishing in Chile is a major industry with a total catch of 4,442,877 tons of fish in 2006. As of 2010, Chile has the seventh largest commercial catch in the world. With over 4,000 km of viable coastline, fishing has been a vital resource for small-scale business and family development for hundreds of years. Due to the Humboldt Current, the Chilean Sea is considered among the most productive marine ecosystems in the world as well as the largest upwelling system. Artisanal fishing is practised all over Chile's 6,435 km long coastline and combines industrial techniques with pre-Hispanic traditions. Recreational fishing tourism in southern Chile's rivers has recently gained worldwide fame attracting actors such as Harrison Ford, Michael Douglas, and Kevin Costner.
Aquaculture started to take off in New Zealand in the 1980s. It is dominated by mussels, oysters and salmon. In 2007, aquaculture generated about NZ$360 million in sales on an area of 7,700 hectares. $240 million was earned in exports.
The fishing industry plays a significant part in the national economy of Pakistan. With a coastline of about 1,120 km, Pakistan has enough fishery resources that remain to be developed. Most of the population of the coastal areas of Sindh and Balochistan depends on fisheries for livelihood. It is also a major source of export earning.
Aquaculture is a major economic activity in Chile. Among the diverse aquacultures practised in Chile, Atlantic salmon aquaculture is by far the largest sector. Apart from salmon and trout, Chilean aquaculture also produces turbots and molluscs, in particular Mytilus platensis, Northern scallops, Pacific oysters, Aulacomya ater, red abalone, and Chilean oysters. In terms of algae Gracillaria chilensis is cultivated and harvested.
South Korea is a major center of aquaculture production, and the world's third largest producer of farmed algae as of 2020.
Panulirus ornatus is a large spiny lobster with 11 larval stages.
"dredge oyster" means the mollusc known as Tiostrea chilensis
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Commercial mollusks | ||
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| Marine gastropods |  | |
| Land and freshwater gastropods | ||
| Free-swimming marine bivalves | ||
| Infaunal bivalves | ||
| Sessile bivalves | ||
| Freshwater bivalves | ||
| Cephalopods | ||
| Techniques | ||
