Selection of mangrove species for shrimp based silvo-aquaculture in the coastal areas of Bangladesh

Samenvatting

The purpose of this work was to assemble information with which to help identify and select mangrove species most likely to be useful and locally acceptable for use in transforming the dominant current non-mangrove shrimp culture practice in Bangladesh towards more sustainable shrimp silvo-aquaculture in the coastal regions of the country. We reviewed current mangrove use in the extensive aquaculture setting, compiled published evidence on mangrove properties and characteristics that influence their suitability for such use and assessed farmer preferences of the various species. Thirteen mangrove species (all of which are available in Bangladesh) were documented as being used in silvo-aquaculture system in the tropics. Followed by these already “established” mangrove species, Aegialitis rotundifolia, Heritiera fomes and Lumnitzera racemosa could be enlisted as additional “optional” mangrove species to consider, while Ceriops decandra, Excocaria agallocha and Phoenix paludosa were found to be unsuitable for silvo-aquaculture. Based on their experience and indigenous knowledge on mangroves, shrimp farmers ranked (in declining order of preference) Sonneratia apetala, S. caseolaris, Avicennia officinalis, Nypa fruticans, Bruguiera sexangula, Heritiera fomes, and also, the mangrove-associate wild rice species Oryza coarctata as the most suitable species to be used for promoting silvo-aquaculture in the coastal areas of Bangladesh. Thus, the focus group interviews with the farmers not only identified which mangroves enjoy most local support for use in transforming current shrimp culture towards more sustainable shrimp silvo-aquaculture but also provided additional leads for species interesting to further investigation into their suitability for silvo-aquaculture.