Aqua-mangrove integrated farming: shrimp and mud crab culture in coastal and inland tidal flats with existing reforested or natural growth of mangroves
Abstract
Throughout the tropics, mangroves are being destroyed at an increasing rate for the development of aquaculture ponds. In the Philippines, for instance, mangroves were about 400,000 to 500,000 ha in 1918 but were reduced to 100,564 ha in 1987. On the average, about 3,500 ha of mangroves are lost every year in the country to accommodate the aquaculture industry (Baconguis et al., 1990). Loss of mangroves means loss of habitat, fishery, income, and livelihood for many coastal inhabitants. The annual catches of major fishing grounds in the Philippines were positively correlated with the areas of existing mangroves (Bagarinao, 1998). Restoration programs of the government such as mangrove reforestation and afforestation were attempted but could not catch up with the unending destruction. An alternative source of income which is directly supportive of resource management was therefore proposed to mitigate ecosystem degradation with the fisher communities in mind.
Fishing villages in the Philippines are generally located in the fringes of arable land along coastal plains and are dependent on fishing as a source of income. The common denominator of these villages is the presence of large areas of tidal flats with existing mangroves. To utilize the aquaculture potential of these mangroves, aqua-mangrove integrated farming development projects were introduced to provide alternative livelihood for the fishers in the village. This integrated approach to conservation and utilization of mangrove resource allows for maintaining a relatively high level of integrity in the mangrove area while capitalizing on the economic benefits of brackishwater aquaculture. The projects took off from the concept of co-management, that is, taking into account the partnership between the local community, the local government unit, and the SEAFDEC Aquaculture Department (SEAFDEC/AQD) in the management of the project.
Source
In: Tadokoro, Y., Sulit, V.T., Abastillas, R.B. Technologies in Mangrove-Friendly Aquaculture. Final Report of and Papers Presented to the On-Site Training on Mangrove-Friendly Aquaculture, 19-30 April 1999. Hai Phong City, Socialists Republic of Vietnam. Tigbauan, Iloilo, Philippines: Southeast Asian Fisheries Development Center, Aquaculture Department. pp. 157-188
Subject
Crustacea; Shrimp culture; Mud crab culture; Mangrove; Aquasilviculture; Site selection; Cages -- Design and construction; Cage culture; Transportation; Stocking organisms; Acclimation; Feed; Feeding; Economic analysis; Polyculture; Crab fattening; Crabs; Mud crab; Milkfish; Shrimps; Giant tiger shrimp; Scylla serrata; Scylla tranquebarica; Scylla olivacea; Chanos chanos; Penaeus monodon
Type
Conference paperCollections
- Conference Proceedings [283]
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Article
Mud crab pen culture: replacement of fish feed requirement and impacts on mangrove community structure.
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Conference paper
Mangroves as mud crab habitats
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Article
Pen culture of mud crab Scylla serrata in tidal flats reforested with mangrove trees
-Aquaculture , 2002 - ElsevierGrowth and survival of mixed sex mud crabs Scylla serrata (Forskal), held in 200 m2 pens located in reforested mangrove tidal flats, were evaluated. The effects of stocking density (0.5 or 1.5 m−2) and feed (salted fish bycatch or a mixed diet of 75% salted brown mussel flesh and 25% salted fish bycatch) were determined in a replicated factorial experiment. Duration of the experiment was 160 days. There were no significant differences (P>0.05) in growth, apparent feed conversion ratio (FCR), survival, and production among the two types of feed. Regardless of feed, the mean±SE FCR of 5.30±0.34 and survival of 56.00±1.90% at 0.5 m−2 stocking density were significantly better (P<0.05) than at 1.5 m−2 stocking density (7.6±0.63 FCR and 33.00±3.61% survival). However, growth was not significantly affected by stocking density. Cost–return analysis on a per crop per 200 m2 basis showed that the use of either of the two stocking densities with either diet was economically viable with a return on capital investment of 49–68%. However, crabs stocked at 1.5 m−2 and fed a mixed diet of 75% salted brown mussel flesh and 25% salted fish bycatch is more profitable. The integration of crab aquaculture within natural mangroves is therefore feasible in the Philippines, providing both immediate and long-term commercial and environmental benefits.
