Hundreds of species of shrimp inhabit the brackish and marine waters of the globe. Most are rare, very small, or not suitable for human consumption. All farm-raised shrimp and most of the shrimp caught by fishermen belong to the Penaeidae family of decapod crustaceans and are referred to as "penaeids". The genus name is Penaeus. In 2006, the giant tiger shrimp (Penaeus monodon) and the western white shrimp (Penaeus vannamei) probably accounted for approximately 85% of the shrimp produced on farms around the world.
Western White Shrimp (Penaeus vannamei): Native to the Pacific coast of Central and South America (from Mexico to Peru), P. vannamei is the leading farm-raised species in the Western Hemisphere, representing more than 99% of production. White shrimp can be stocked at small sizes, have a uniform growth rate and reach a maximum length of 230 millimeters. They breed in captivity better than monodon, but not as readily as many of the other penaeids (below). Hatchery survivals are high, from 50 to 60%. Throughout Latin America, hatcheries maintain captive stocks of vannamei broodstock, some of them pathogen-free, some of them pathogen-resistant and some of them in captivity for 30 years. Farmers throughout Asia are switching to vannamei, and it has now become the dominant species around he world.
Giant Tiger Shrimp (Penaeus monodon): Named for its huge size and banded tail, P. monodon accounts for about a third of the farmed shrimp coming out of Asia. Native to the Indian Ocean and the southwestern Pacific Ocean from Japan to Australia, "tigers" are the largest (maximum length 363 millimeters) and fastest growing of the farmed shrimp. They tolerate a wide range of salinities, but shortages of wild broodstock often exist, captive breeding is difficult and hatchery survivals are low (20 to 30%). Tigers are very susceptible to two of the most lethal shrimp viruses: yellowhead and whitespot.
Western Blue Shrimp (Penaeus stylirostris): Native to the Pacific coast of Central and South America (from Mexico to Peru), western blue shrimp were a popular farmed species in the western hemisphere until the late 1980s when the IHHN virus attacked them but not vannamei. Fortunately, captive stocks of stylirostris were maintained at several locations around the world. Through selective breeding, these stocks developed resistance to the IHHN virus.
From 1992 to 1997, when vannamei stocks everywhere in the western hemisphere were being devastated by the Taura virus, shrimp farmers took a second look at "stylies" and found that some of the captive stocks were resistant to IHHN and Taura! Consequently, in 1997, stylies made a comeback on farms throughout the western hemisphere, especially in Mexico. Fast growers, stylies look a lot like vannamei and have similar cultural requirements. They tolerate significantly lower water temperatures than vannamei, but prefer higher oxygen levels, turbidity, salinities and protein levels. Stylies are aggressive feeders and will roam around the pond looking for feed. They like deep ponds and high water quality. Shipment of stylie broodstock and seedstock is difficult, and stylies are more intent on escaping from ponds than are vannamei.
Although stylirostris farming has declined dramatically in the Western Hemisphere, the South Pacific nation of New Caledonia farms it exclusively and has its own strain that has been maintained in captivity for thirty years.
Red, White and Blue Shrimp: From the consumer's point of view, stylirostris and vannamei are nearly identical and can be mixed together and sold as western white shrimp.
At the Fourth Latin American Aquaculture Congress and Exhibition (Panama, October 2000), Shrimp News asked Bill More (wrmore@comcast.com), one of the founders of shrimp farming in the Western Hemisphere, about the distribution of the penaeids along the western coast of Latin America. More said:
Shrimp caught off the northern, Pacific coast of Mexico are primarily P. californensis; those caught off the southern Pacific coast are probably vannamei or stylirostris. Vannamei peaks in Nicaragua where it represents approximately 70% of the catch.
Off Ecuador, vannamei represents around 20% of the catch, and occidentalis and stylirostris probably represent 30% each. In Peru, occidentalis begins to disappear and you get more vannamei and stylirostris. Stylirostris is more abundant than vannamei in every country with the exception of Nicaragua. Vannamei lives on different types of bottoms than occidentalis and stylirostris.
Chinese White Shrimp (Penaeus chinensis, also known as P. orientalis): Native to the coast of China and the west coast of the Korean peninsula, Chinese white shrimp grow better in lower water temperatures (down to 16 degrees Celsius) than vannamei and monodon, tolerate muddy bottoms and very low salinities—and, unlike the above species, Chinese white shrimp readily mature and spawn in ponds. On the negative side, they have a high protein requirement (40 to 60%), a small size (maximum length of 183 millimeters), and a lower meat yield (56%) than monodon (61%) and vannamei (63%). Also, chinensis appears to be more susceptible to viruses than vannamei, which is replacing it in southern China and on Hainan Island.
Japanese Kuruma Shrimp (Penaeus japonicus): Native to the Indian Ocean and the Southwestern Pacific Ocean from Japan to Australia, kuruma shrimp are farmed in Japan and Australia. Live kuruma shrimp bring outrageously high prices in Japan, as high as $100 a pound! It's relatively easy to ship live animals without water, they mature and spawn in ponds, and they tolerate low water temperatures better than any other farmed species, down to 10 degrees Celsius. They require clean, sandy bottoms and high protein diets (55%). Markets are limited to Japan. Australia has a few farms that export japonicus to Japan.
Indian White Shrimp (Penaeus indicus): Indicus is raised on extensive farms throughout Southeast Asia, and it is widely cultured in India, the Middle East and eastern Africa. It tolerates low water quality better than monodon, it likes high salinities, high temperatures and high densities, and it is readily available in the wild. Indicus also reaches sexual maturity and spawns in ponds. Iranian shrimp farms produces more indicus than any other country.
Native to the Indian Ocean from southern Africa to northern Australia and to all of Southeast Asia, indicus is one of the major species in the region's commercial fishery. It is the most important species caught off the east coast of Africa and is probably the most important commercial species in India, especially in the inshore fishery and in the rice field farming around Kerala.
On September 9, 2001, Michel Autrand (michel.autrand@wanadoo.fr), one of the pioneers of shrimp farming in New Caledonia, responding to a question on the Shrimp List, a mailing list for shrimp farmers (shrimp-subscribe@yahoogroups.com), said:
I started working with indicus in 1975, in New Caledonia. More recently, I have worked with them in Madagascar. Growth up to 14-15 grams is good between 24 and 32°C, but slow below 24°C, except at very low densities (less than two animals per square meter). Indicus continues to grow in high salinity waters up to 42 parts per thousand. I don't have experience with higher salinites, but, in Iran, I think salinities easily reach 45 ppt and more. Indicus seems to be less tolerant of low salinites than monodon. On a Madagascar farm, where salinities ranged between 0 and 2 ppt for two months, we had some monodon (20 per square meter) and indicus (2/m2) in the same high turbidity pond. Mortalities were much greater among the indicus.
Banana Shrimp (Penaeus merguiensis): Raised on extensive farms throughout Southeast Asia, merguiensis is a also a "white" shrimp that has attracted attention because it tolerates low water quality better than monodon, it can be grown at high densities, and it is readily available in the wild. Native to the Indian Ocean from Oman to western Australia, to Southeast Asia from the Philippines to Indonesia, and to eastern Australia, merguiensis is heavily fished throughout its range, especially in Australia.
An article in the December 2001 issue of World Aquaculture (http://www.was.org) reviewed merguiensis's prospects as a farmed species:
Wild-caught breeders are cheap compared to monodon. Each female yields between 100,000 and 200,000 eggs per spawn, which is relatively low, but the low price of broodstock more than compensates for this, and the larvae and postlarvae are much easier to convert to prepared feeds. More importantly, adults mature and spawn naturally in captivity.
Advantages: Easy larval rearing, survive well in extensive and semi-intensive ponds, tolerate a wide range of salinities and temperatures, low protein requirement, and minimal size variation
Disadvantages: slow growth rate, limited information on biology and culture, low survival in intensive ponds (not confirmed by research), die quickly at harvest, and no species-specific commercial feeds
Farmers in southeastern Queensland, Australia, were encouraged to stock their ponds with banana prawns and their results were good, with production of 5 tons per hectare. Postlarvae from pond-reared broodstock have been grown successfully to market size in five months. Observations show that banana shrimp grow much faster in tanks or ponds that are rich in detritus and algae.
Brown Tiger Shrimp (Penaeus esculentus): Native to the west, north and east coasts of Australia, esculentus, the brown tiger shrimp, looks a lot like the giant tiger shrimp (monodon), only smaller and browner. Uniquely Australian, it is fished year-round and is often caught along with the green tiger shrimp (semisulcatus).
An aggressive detrital feeder, esculentus has potential in bacterial-based systems.
The New Wave, a special publication of the World Aquaculture Society (http://www.was.org), contains an interesting report on the farming potential of esculentus by Sandy Keys and Peter Crocos, researchers in Australia. They conducted commercial growout trials, developed a special diet, optimized larval and juvenile rearing protocols and investigated protocols for zero-exchange production. Esculentus postlarvae were grown on a farm for commercial sale to Japanese and Australian markets in 1997 and 1999. Survival in the hatchery phase (egg to PL-15) was improved by reducing the rearing temperature from 28° to 26°C. Juvenile growth was promoted by the addition of structures conditioned with natural biota during the early growout phase. Three generations of viable progeny were produced from captive broodstock using techniques developed for japonicus.
The Atlantic White Shrimp (Penaeus setiferus): The Atlantic white shrimp can be found along the Atlantic coast of the USA from New Jersey to Florida and everywhere in the Gulf of Mexico. It looks a lot like P. vannamei, but can easily be identified by its unique genitalia. At full maturity, setiferus reaches 200 millimeters (7.9 inches). It can’t compete with vannamei as a growout species, but because it’s native to the USA, it can be raised as bait and sold to recreational fishermen.
With the threat of wild setiferus being depleted in the Gulf of Mexico by commercial bait fishermen and a practically nonexistent live bait shrimp industry in South Carolina, the Waddell Mariculture Center is developing technology to supply live bait year-round. The three-year project to raise a disease-free line of setiferus is being funded with a federal grant. Al Stokes, manager of the Waddell Center and a wildlife biologist for the state Department of Natural Resources, said he hopes Waddell can pass the project on to the private sector when the grant expires in December 2008.
Bait shrimp are marketed at much smaller sizes (around six grams) than food shrimp. Setiferus is more cold tolerant than vannamei, and in recirculating, greenhouse-enclosed, raceway systems, it can be grown at very high densities.
Supplying bait to more than nine million recreational saltwater fisherman each year has become a major industry in the USA that relies on the capture of wild shrimp. Some states are concerned that the increasing demand for bait shrimp may not be sustainable and have already imposed new regulations on bait fishermen to protect the resource.
Bait shrimp hatcheries could operate year-round and provide stable prices and supplies to bait dealers, something they don’t have now. Test markets indicate that hatchery-reared bait shrimp handle and perform well during transport, in the bait shop—and on the hook.
Freshwater Prawns (Macrobrachium spp.): World production of prawns is rising. The genus Macrobrachium, which includes about 200 species, almost all of which live in freshwater for at least part of their life cycle, is circumtropical and native to all continents except Europe. The favored species for farming has always been M. rosenbergii, sometimes called the "giant river prawn" or the "Malaysian prawn", but recently, China began culturing M. nipponense, a species native to Japan, Taiwan and Vietnam, which has also been introduced into Russia, the Philippines and Singapore. In India, some M. malcolsmonni are farmed. In the United States, there are several hundred small freshwater prawn farms that grow M. rosenbergii.
Beginning in 2000, freshwater prawns (defrosted shell-on tails) began showing up in USA grocery stors. They look a lot like giant tiger shrimp, but they're bigger, chunkier, lighter in color, and their shells are always on. In fact, if you look carefully at the second tail segment, you can easily distinguish prawns from shrimp. If the bottom part of the shell on the second tail segment overlaps the shell on the first and third segments, it's a freshwater prawn.
Prawns fight a lot and don't adapt well to high densities.
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