World Aquaculture 11 Table 1. Mithraculus forceps larval and juvenile culture conditions tested, protocol previously suggested, protocol suggested through modeling and productivity (per tank.year -1 for larval culture and per m2.year -1for juvenile culture) improvement through modeling (NHA – newly hatched Artemia; EAM- 2days old Artemia enriched with Algamac 3050™; Amphora (microalgae); FNHA- frozen newly hatched Artemia; C.P. – commercial pellets; juv.- juveniles; * - it was not object of optimization modeling) Protocol Protocol Variable Conditions previously suggested Productivity tested suggested after modeling improvement 25ºC Temperature 28ºC 28ºC* - 28ºC NHA Diet NHA NHA* - EAM Larval 10 larvae.L-1 Culture Stocking 20 larvae.L-1 40 60 50% density 40 larvae.L-1 larvae.L-1 larvae.L-1 80 larvae.L-1 1 prey.mL-1 Prey 4 preys.mL-1 7 10 12% density 7 preys.mL-1 preys.mL-1 preys.mL-1 12 preys.mL-1 25ºC Temperature 28ºC 28ºC* - 28ºC NHA Amphora FNHA NHA Diet C.P. NHA + 26% NHA + Amphora Amphora NHA + FNHA Juvenile NHA + C.P. Culture Prey 8 8 8* - density preys.mL-1 preys.mL-1 preys.mL-1 225 juv.m-2 Stocking 1130 juv.m-2 3395 12900 280% density 3395 juv.m-2 juv.m-2 juv.m-2 13580 juv.m-2 which optimum is 60 larva/L. For prey density, survival (%) = -3.14 + 13.24 x PD – 0.64 x PD2 (Figure 3), which optimum is 10 preys/mL. Diet effect on juvenile survival during growout was modeled with a logistic model Juveniles’ Survival = 100 + (Figure 4), where Φ2=88.04 and Φ3=6.19 for NHA, Φ2=40.88 and Φ3=15.54 for Amphora, Φ2=68.42 and Φ3=9.71 for FNHA, Φ2=36.52 and Φ3=8.41 for CP, Φ2=60.85 and Φ3=12.76 for NHA + Amphora, Φ2=62.48 and Φ3=8.92 for NHA + FNHA, and Φ2=70.99 and Φ3=8.92 for NHA + CP. The effect of stocking density was modeled with a linear (polynomial) model: Juvenile survival (%) = 100 + bx + cx2 +dx3 Fig. 4. Effect of diet and on juvenile culture. (Figure 5), where x are days post metamorphosis and where b = - 3.6 , c = 0.17, and d = -2.65x10-3 for 226 crabs/m2, b = -1.24, c = 0.02, and d = - 9x10-5 for 1132 crabs/m2, b = -0.35
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