Prawn, Giant River, prawns

Macrobrachium rosenbergii

Method of production — Farmed
Production country — Bangladesh
Production method — Extensive pond
Picture of Prawn, Giant River, prawns

Sustainability rating three info

Sustainability overview

Unlike production of marine shrimp, culture of freshwater prawn in Bangladesh takes place inland, away from coastal habitats. This species is therefore not associated with saltwater intrusion or the loss of ecosystem services caused by mangrove deforestation. The majority of production is extremely extensive in nature and when supplementary feed is provided it predominantly consists of wild, local freshwater apple snail. This means that production of this species has very little reliance on wild fisheries - although small amounts of fishmeal may occasionally be included in homemade feeds. A negative driving factor, however, is that hatchery production of freshwater prawns in Bangladesh is entirely reliant on wild-caught broodstock, additionally, hatchery production is extremely limited and the majority of post larvae used by the sector are collected from the wild, which results in high levels of bycatch. Although the government have a legislative framework in place to manage the sector, its capacity to effectively enforce and monitor compliance with these measures is limited.

Feed Resources

Criterion Score: 6

Giant river prawn produced in Bangladesh is mainly cultured in extensive systems without the addition of commercially prepared diets. Feed for the prawn comes from naturally occurring plankton and biota in the pond - often this natural diet is supplemented with wild snail meat.

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Environmental Impacts

Criterion Score: 1

Competition for freshwater can occur with other agricultural users, habitat impacts are known but not in areas of high sensitivity, the use of chemicals, disease outbreaks and their regulation is not known.The biggest issue of environmental concern for giant river prawn production in Bangladesh is that the vast majority of the sector relies on wild-caught juveniles. Furthermore, the few PLs that are produced by hatcheries are the progeny of wild broodstock. Neither of these wild-sourcing practices are sustainable and the abundance of wild M. rosenbergii in Bangladesh is in decline

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Fish Health and Welfare

Criterion Score:-1

No data was identified on the topic of welfare and humane slaughter in literature that pertains to the giant river prawn farming sector in Bangladesh.

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Management

Criterion Score: -3 

Despite the existence of a regulatory framework for the sector, it is evident that confusion exists between the myriad of agencies involved and, due to a lack of capacity, enforcement of these management measures is weak.

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Production method

Extensive pond

Freshwater prawns are farmed in a similar way to other prawn species. They are raised in hatcheries and then transferred to open freshwater ponds to grow out.

Biology

This large freshwater shrimp is native to the Indo-Pacific region, northern Australia and Southeast Asia. Males can reach total length of 320 mm; females 250 mm. Body usually greenish to brownish grey, sometimes more bluish, darker in larger specimens. Morphologically complex: eleven larval stages ; adult males of 3 types: ‘Small males’ which , if conditions allow, metamorphose into bigger ‘Orange Claws’ which in turn can become ‘Blue Claws’ whose striking second, claw-bearing legs may become twice as long as their body. All 3 types are sexually active. While M. rosenbergii is considered a freshwater species, eggs are laid in estuaries & the larval stage of the animal depends on brackish water . The female carries the fertilised eggs with her until they hatch; the time may vary, but is generally less than three weeks. Females lay 10,000 to 50,000 eggs up to five times per year. Once the individual shrimp has grown beyond the planktonic stage and become a juvenile, it will live entirely in freshwater. Adult prawns can walk as well as swim and can climb up vertical surfaces (small waterfalls, weirs, etc.) and cross land. Farmed animals have escaped into the wild. Larvae mostly consume zooplankton (mainly minute crustaceans), very small worms, and larval stages of other crustaceans. Post larvae and adults are omnivorous, eating algae, aquatic plants, molluscs, aquatic insects, worms, and other crustaceans

References

Afroz T, Alam S. 2012. Sustainable shrimp farming in Bangladesh: A quest for an Integrated Coastal Zone Management. Ocean & Coastal Management 71 (2013) 275-283

Afroz T, Alam S. 2012. Sustainable shrimp farming in Bangladesh: A quest for an Integrated Coastal Zone Management. Ocean & Coastal Management 71 (2013) 275-283.

Ahmed N. 2013. Climate Change Impacts on Human Health in Freshwater Prawn Farming Communities in Bangladesh. March 2013 World Aquaculture, WWW.WAS.ORG.

Ahmed N, Garnett ST. 2010. Sustainability of Freshwater Prawn Farming in Rice Fields in Southwest Bangladesh. Journal of Sustainable Agriculture, 34: 6, 659 - 679.

Belton B. 2016. Shrimp, prawn and the political economy of social wellbeing in rural Bangladesh. Journal of Rural Studies 45 (2016) 230e242.

DOF & Bangladesh Shrimp and Fish Foundation. 2015. CODE OF CONDUCT For Selected 10 Segments of the Shrimp Aquaculture Industry in Bangladesh.

http://mofl.portal.gov.bd/sites/default/files/files/mofl.portal.gov.bd/legislative_information/ef408fe7_b347_4e56_9251_10bb70459bfd/Code%20of%20Conduct%20_FinalVersion_25_07_2015%20%281%29.pd

Didar-Ul Islam SM, Bhuiyan MAH. 2016. Impact scenarios of shrimp farming in coastal region of Bangladesh: an approach of an ecological model for sustainable management. Journal of the European Aquaculture Society, Aquacult Int DOI 10.1007/s10499-016-9978-z

FAO 2004-2018. Cultured Aquatic Species Information Programme. Macrobrachium rosenbergii. Cultured Aquatic Species Information Programme. Text by New, M. B. In: FAO Fisheries and Aquaculture Department [online]. Rome. Updated 1 January 2004. [Cited 7 September 2018].FAO: Farming freshwater prawns, a manual for culture of M.rosenbergii. Available online at: http://www.fao.org/docrep/005/y4100e/y4100e08.htm#P1851_284433F. Paez Osuna: The environmental impact of shrimp aquaculture: a global perspective. Environmental Pollution 112 (2001) 229-231

Giri C, Zhu Z, Tieszen LL , Singh A , Gillette S, Kelmelis JA. 2008. Mangrove forest distributions and dynamics (1975-2005) of the tsunami-affected region of Asia. Journal of Biogeography (J. Biogeogr.) (2008) 35, 519-528. https://www.researchgate.net/publication/227740299_Mangrove_forest_distribution_and_dynamics_1975-2005_of_the_Tsunami_affected_region_of_Asia_J_Biogeogr

HMRC. 2018. HM Revenue & Customs trade statistics www.uktradeinfo.com