This thesis is concerned with a community approach to the farming and fattening of the Mangrove mud crab Scylla serrata Forskal in Mtwapa Creek on the Kenyan coast. A study into the natural distribution of the crab in the Rhizophera mucronata zone revealed a preferred habitat which was the intertidal mud banks, for crabs of 6.1-9 and 9.1-12 cm carapace widths, however crabs of 3.1-6cm showed preference for mangrove canopy cover between 0-25%. Based on the results of this initial study two crap pens were constructed, the first in a chosen hypothetically optimum site inside the mangrove stand, enclosing mangroves without incurring any damage or destruction, and the second in contrasting conditions in a natural clearance, with no mangrove presence. Crab pen structures were based on traditional tidal fish traps of the area. Results after a 43 day fattening period showed harvested crabs solely from the mangrove integrated pen, of these crabs, all were female, no crabs were recovered from the second pen with no mangal presence. Pen structures proved successful for the mangrove pen, for female crabs, with 100% survival and harvest rates. Furthermore feeding crabs on trash and kitchen waste which was freely available proved viable, female crabs growing an average 2.13g/crab/day. In terms of cost benefit analysis, the mangrove integrated pen proved viable with no capital outlay or operational costs with the exception of labour or man hours, calculated profit levels for female crab fattening was 50%. The study provides a positive introduction to community mud crab culture in East Africa, which can bring direct benefit to severely income defecit local communities around mangrove habitats, whilst also promoting and facilitating effective mangrove conservation. |
