The Info List - Freshwater Prawn Farming

A freshwater prawn farm is an aquaculture business designed to raise and produce freshwater prawns or shrimp1 for human consumption. Freshwater
prawn farming shares many characteristics with, and many of the same problems as, marine shrimp farming. Unique problems are introduced by the developmental life cycle of the main species (the giant river prawn, Macrobrachium
rosenbergii).[1] The global annual production of freshwater prawns (excluding crayfish and crabs) in 2003 was about 280,000 tons, of which China
produced some 180,000 tons, followed by India
and Thailand
with some 35,000 tons each. Additionally, China
produced about 370,000 tons of Chinese river crab (Eriocheir sinensis).[2]


1 Species 2 Biology of Macrobrachium
rosenbergii 3 Technology 4 Economics 5 See also 6 Footnotes 7 References 8 External links

Species[edit] All farmed freshwater prawns today belong to the genus Macrobrachium. Until 2000, the only species farmed was the giant river prawn ( Macrobrachium
rosenbergii, also known as the Malaysian prawn). Since then, China
has begun farming the Oriental river prawn (M. nipponense) in large quantities, and India
farms a small amount of monsoon river prawn (M. malcolmsonii). In 2003, these three species accounted for all farmed freshwater prawns, about two-thirds M. rosenbergii and one-third M. nipponense. About 200 species in the genus Macrobrachium
live in the tropical and subtropical climates on all continents except Europe and Antarctica. Biology of Macrobrachium
rosenbergii[edit] Giant river prawns live in turbid freshwater, but their larval stages require brackish water to survive. Males can reach a body size of 32 cm; females grow to 25 cm. In mating, the male deposits spermatophores on the underside of the female's thorax, between the walking legs. The female then extrudes eggs, which pass through the spermatophores. The female carries the fertilized eggs with her until they hatch; the time may vary, but is generally less than three weeks. A large female may lay up to 100,000 eggs. From these eggs hatch zoeae, the first larval stage of crustaceans. They go through several larval stages before metamorphosing into postlarvae, at which stage they are about 8 mm long and have all the characteristics of adults. This metamorphosis usually takes place about 32 to 35 days after hatching. These postlarvae then migrate back into freshwater. There are three different morphotypes of males. The first stage is called "small male" (SM); this smallest stage has short, nearly translucent claws. If conditions allow, small males grow and metamorphose into "orange claw" (OC) males, which have large orange claws on their second chelipeds, which may have a length of 0.8 to 1.4 times their body size. OC males later may transform into the third and final stage, the "blue claw" (BC) males. These have blue claws, and their second chelipeds may become twice as long as their body.[3] Male M. rosenbergii prawns have a strict hierarchy: the territorial BC males dominate the OCs, which in turn dominate the SMs. The presence of BC males inhibits the growth of SMs and delays the metamorphosis of OCs into BCs; an OC will keep growing until it is larger than the largest BC male in its neighbourhood before transforming. All three male stages are sexually active, though, and females which have undergone their premating molt will cooperate with any male to reproduce. BC males protect the females until their shells have hardened; OCs and SMs show no such behavior. Technology[edit]

prawn farm in Bangladesh.

Giant river prawns have been farmed using traditional methods in Southeast Asia
Southeast Asia
for a long time. First experiments with artificial breeding cultures of M. rosenbergii were done in the early 1960s in Malaysia, where it was discovered that the larvae needed brackish water for survival. Industrial-scale rearing processes were perfected in the early 1970s in Hawaii, and spread first to Taiwan
and Thailand, and then to other countries. The technologies used in freshwater prawn farming are basically the same as in marine shrimp farming. Hatcheries produce postlarvae, which then are grown and acclimated in nurseries before being transferred into growout ponds, where the prawns are then fed and grown until they reach marketable size. Harvesting is done by either draining the pond and collecting the animals ("batch" harvesting) or by fishing the prawns out of the pond using nets (continuous operation). Due to the aggressive nature of M. rosenbergii and the hierarchy between males, stocking densities are much lower than in penaeid shrimp farms. Intensive farming is not possible due to the increased level of cannibalism, so all farms are either stocked semi-intensively (4 to 20 postlarvae per square metre) or, in extensive farms, at even lower densities (1 to 4/m²). The management of the growout ponds must take into account the growth characteristics of M. rosenbergii: the presence of blue-claw males inhibits the growth of small males, and delays the metamorphosis of OC males into BCs. Some farms fish off the largest prawns from the pond using seines to ensure a healthy composition of the pond's population, designed to optimize the yield, even if they employ batch harvesting. The heterogeneous individual growth of M. rosenbergii makes growth control necessary even if a pond is stocked newly, starting from scratch: some animals will grow faster than others and become dominant BCs, stunting the growth of other individuals. The FAO
considers the ecological impact of freshwater prawn farming to be less severe than in shrimp farming. The prawns are cultured at much lower densities, meaning less concentrated waste products and a lesser danger of the ponds becoming breeding places for diseases. The growout ponds do not salinate agricultural land, as do those of inland marine shrimp farms. However, the lower yield per area means that the income per Ha is also lower and a given area can support fewer humans. This limits the culture area to low value lands where intensification is not required. Freshwater
prawn farms do not endanger mangroves, and are better amenable to small-scale businesses run by a family.[4] However, like marine farmed shrimp, M. rosenbergii is also susceptible to a variety of viral or bacterial diseases,[5] including white tail disease,[6] also called "white muscle disease".[7] Economics[edit] The global annual production of freshwater prawns in 2003 was about 280,000 tonnes, of which China
produced some 180,000 tonnes, followed by India
and Thailand
with some 35,000 tonnes each. Other major producer countries are Taiwan, Bangladesh, and Vietnam. In the United States, only a few hundred small farms for M. rosenbergii produced about 50 tonnes in 2003.[2] See also[edit]

Crustaceans portal

The technologies used in freshwater prawn farming, but also the ecological problems associated with this industry, are basically the same as for marine shrimp farming and are discussed in that article.

Footnotes[edit] ^1 The terminology is sometimes confusing as the distinction between "shrimp" and "prawn" is sometimes blurred. Recent aquaculture literature increasingly uses the term "prawn" only for the freshwater forms of palaemonids and "shrimp" for the marine penaeids.[8] References[edit] The main reference for this article was a comprehensive farming manual of the FAO.[1]

^ a b New, M. B.: Farming Freshwater
Prawns; FAO
Fisheries Technical Paper 428, 2002. ISSN 0429-9345. ^ a b Data extracted from the FAO
Fisheries Global Aquaculture Production Database for freshwater crustaceans. The most recent data sets are for 2003 and sometimes contain estimates. Accessed June 28, 2005. ^ Wynne, F.: Grow-out Culture of Freshwater
Prawns in Kentucky, 2000. Last accessed July 4, 2005. ^ FAO: Cultured Species Fact Sheet M. rosenbergii; accessed June 30, 2005. Has images. ^ Tonguthai, K.: Diseases of the Freshwater
Prawn, Macrobrachium rosenbergii, AAHRI Newsletter 4(2), Aquatic Animal Health Research Institute, Bangkok University; December 1997. ^ Sahul Hameed, A. S.: White tail disease of Macrobrachium rosenbergii, NACA, 2003. ^ Sahul Hameed, A. S.: White Tail Disease - Disease Card, NACA, 2005. ^ Indian Aquaculture
Authority: Shrimp
and the Environment - An Environment Impact Assessment Report Archived 2011-07-16 at the Wayback Machine., ch. 2; IAA report, April 2001.

External links[edit]

of Texas

Wild fisheries

Fishing industry

Commercial fishing List of harvested aquatic animals by weight Trawling Pair trawling Midwater trawling Bottom trawling Seining Gillnetting Longlining Trolling Dredging Fishing vessels Power block

Fish processing

Fish factory Factory ship Fish preservation Slurry ice Dried fish Filleted fish Gibbing Salmon
cannery Salted fish Smoked fish Kippers more...

Fish products

Seafood Fish as food Caviar Cod liver oil Fish roe Fish emulsion Fish meal Fish hydrolysate Fish oil Fish protein powder Fish sauce Gravlax Hákarl Lox Lutefisk Rakfisk Shrimp
paste Surimi Surströmming Seafood
list Sea vegetables Algae Crustaceans Molluscs more...

Fish marketing

Live fish trade Shrimp
marketing Chasse-marée Fishmonger Fishwife Worshipful Company of Fishmongers

Fish markets

Billingsgate Fulton Maine Avenue English Market Scania Tsukiji more...

Area fisheries

World fish production Fishing by country Fishing banks Other areas

and farmed fisheries


engineering Aquaponics Best practices Copper alloys Fisheries and aquaculture research institutes Geothermal energy and aquaculture Inland saline Integrated multi-trophic Mariculture Antimicrobials Offshore Organic Raceway Recirculating

Fish farming

Broodstock Catfish Cobia Fish diseases and parasites Fish farming Fish feed Fish hatchery Fish stocking Spawning bed Salmon Tilapia Tailwater US hatcheries


Giant kelp Microalgae Microalgal bacterial flocs Photobioreactor Raceway pond Seaweed

Other species

Brine shrimp Coral Freshwater
prawns Geoduck Hirudiculture Marine shrimp Octopus Oysters Scallops Sea cucumber Sea sponges Turtles

By country

Alaska Australia Canada Chile China East Timor Federated States of Micronesia Fiji Indonesia Kiribati Madagascar Marshall Islands Nauru New Zealand Palau Papua New Guinea Samoa Solomon Islands South Africa South Korea Tonga Tuvalu Vanuatu

v t e

Principal commercial fishery species groups


Large pelagic fish

Mackerel Salmon Saury Shark Swordfish Tuna

albacore bigeye Atlantic bluefin Pacific bluefin southern bluefin skipjack yellowfin

Forage fish

Anchovy Capelin Herring Ilish Menhaden Sardines Shad Sprat


Demersal fish

Catfish Cod

Atlantic Pacific Alaska pollock


flounder halibut plaice sole turbot

Haddock Mullet Orange roughy Pollock Rockfish Smelt-whitings Toothfish


Carp Sturgeon Tilapia Trout

Other wild fish

Eel Whitebait more...


Crab Krill Lobster Shrimp more...


Abalone Mussels Octopus Oysters Scallops Squid more...


Sea cucumbers Sea urchin more...



bighead common crucian grass silver

Catfish Freshwater
prawns Gilt-head bream Mussels Oysters Salmon

Atlantic salmon trout coho chinook

Scallops Seaweed Shrimp Tilapia

Commercial fishing World fish production Commercial species Fishing topics