caa a22 4500 605464073 CHVBK 20210128100256.0 cr unu---uuuuu 210128e20150201xx s 000 0 eng 10.1007/s10499-014-9805-3 doi (NATIONALLICENCE)springer-10.1007/s10499-014-9805-3 Comparative performance of wild juvenile mud crab ( Scylla serrata ) in different culture systems in East Africa: effect of shelter, crab size and stocking density [Elektronische Daten] [David Mirera, Per-Olav Moksnes] Grow-out culture of mud crabs Scylla serrata in East Africa is at an earlier development phase and is dependent on wild seed crabs. We assessed three different culture systems (net cages, ponds and pens) in three treatments (shelter, size and density) to evaluate survival and growth in small-scale culture of mud crabs in Kenya. In small nursery cages, we assessed how availability of shelter, stocking density and size-class separation affected cannibalistic rates in small juveniles (20-80mm internal carapace width) in 7-day experiments. The result indicated that shelter and size-class separation decreased cannibalism and mortality with 26 and 31%, respectively, whereas no significant effect was found for different stocking densities. Earthen ponds and mangrove pens were used to compare growth and survival in long-term studies (2-4months) in the presence and absence of shelter. Treatments with and without shelter yielded low overall recovery of crabs (4-26%) indicating high mortality rates, and there was no significant effect of shelter or culture system on survival. In contrast, growth rate was high in both pens and ponds, but significantly lower in pen systems without shelter. Generally, the results indicated that cannibalism is the largest source of mortality in different culture systems (net cages, ponds and pens), and use of shelter and size grading of crabs improved survival significantly. In contrast, growth rates were high and comparable to natural growth in both pond and pen culture when shelter was provided. Using growth models to compare growth and survival in mud crabs from aquaculture studies in the literature, we show that shelter may have a stronger effect on growth than has been previously thought, whereas crab density appears to impact more on crab survival. Thus, improving survival in grow-out culture systems is a challenge that remains to be solved for small-scale mud crab culture in East Africa. Springer International Publishing Switzerland, 2014 Mud crab nationallicence Net cages nationallicence Ponds nationallicence Pens nationallicence Shelter nationallicence Density nationallicence Survival nationallicence Growth nationallicence Mirera David Kenya Marine and Fisheries Research Institute (KMFRI), P.O. Box 81651, Mombasa, Kenya aut Moksnes Per-Olav Department of Biology and Environmental Sciences, Gothenburg University, Box 461, 405 30, Göteborg, Sweden aut Aquaculture International Springer International Publishing 23/1(2015-02-01), 155-173 0967-6120 23:1<155 2015 23 10499 https://doi.org/10.1007/s10499-014-9805-3 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10499-014-9805-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Mirera David Kenya Marine and Fisheries Research Institute (KMFRI), P.O. Box 81651, Mombasa, Kenya aut NATIONALLICENCE 700 1- Moksnes Per-Olav Department of Biology and Environmental Sciences, Gothenburg University, Box 461, 405 30, Göteborg, Sweden aut NATIONALLICENCE 773 0- Aquaculture International Springer International Publishing 23/1(2015-02-01), 155-173 0967-6120 23:1<155 2015 23 10499