Latin American & Caribbean Aquaculture 2019

November 19 - 22, 2019

San Jose, Costa Rica

OPPORTUNITIES AND CONSTRAINTS TO FARM FRESHWATER PRAWNS IN LATIN AMERICA AND CARIBBEAN

Wagner C. Valenti

Centro de Aquicultura da UNESP - CAUNESP
Universidade Estadual Paulista - UNESP
 w.valenti@unesp.br
 

Latin America and Caribbean have a large number of native species of freshwater prawns commercially important . Most of them belong to  the  genus Macrobrachium , but also the genus Cryphiops occurs in Chile and Peru. The  main  species  are M. amazonicum , M. americanum , M. carcinus , M. acanthurus , C. caementarius, and M. tenellun. Most of them have received the attention of the scientific community, and a large effort of research has been done to develop farming protocols .  All of these species have a good market, and prices are high. Nevertheless, commercial farms are still incipient. The most produced species in the subcontinent is the Asiatic Macrobrachium rosenbergii.

Overfishing and habitat destruction have decreased natural stocks, which contribute to the shortage of some native prawns, such as M. carcinus and M. americanum, increasing market prices. However, the giant river prawn M. rosenbergii show some differences in the meat texture and taste, which impair to replace the native species in the traditional markets.

The technology  to produce the Amazon river prawn, M. amazonicum, is well developed. All the others still have important technological constraints, mainly in the hatchery phase.

The main constraints to produce M. amazonicum and M. rosenbergii are the lack of organization of the productive chain, the lack of a specific commercial diet, and the low productivity, compared to marine shrimp and freshwater fish.  Grow-out farmers have difficulties in obtaining  large numbers of postlarvae to stock ponds , whereas  hatcheries frequently can not sell all production, which makes the activity unfeasible. Grow-out farms frequently use diets for marine shrimps, which are very expensive, or for freshwater fish, which normally is unsuitable . Heterogeneous growth and dominant behavior  are  shown  by males of Macrobrachium species  decreasing the stocking densities and productivity.

An immediate solution to these constraints is raising freshwater prawns integrated with other species, such as some fish or rice. In integrated systems, the stocking densities are low,  the use of commercial feed is not necessary and low productivities are compensated by the production of the other species. Macrobrachium species occupy the  pond bottoms, eat on natural biota and wastes, and grow fast in low densities . Success has been demonstrated in the integrated culture with Nile tilapia (Oreochromis niloticus), lambari (Astyanax lacustris), and tambaqui (Colossoma macropomum ). The high price obtained by the prawns adds significant value to the production,  compensating the low crop.

Latin America and  the Caribbean have millions of hectares of fish ponds and rice fields, which are a great opportunity to produce freshwater prawns in integrated systems.

(FAPESP, CNPq)