Assessment of blacklip rock oyster, Saccostrea lineage J, spat growth and survival in recirculating upweller and downweller nursery systems

Figures & data

Figure 1. A, Downweller nursery system; and B, Upweller nursery system.

Figure 2. Dorsoventral measurement (DVM; mm) of Saccostrea lineage J spat in a downweller and upweller nursery system, from 31 to 93 days post hatch (dph). Y-axis intercept line at 5 mm DVM indicates spat size suitable for deployment.

Figure 3. Total biomass (g) of Saccostrea lineage J spat in a downweller and upweller nursery system from 31 to 93 days post hatch (dph).

Figure 4. Development photographs and mean dorsoventral shell measurement (DVM ± standard error, mm) of Saccostrea lineage J spat at grade sizes. A, 0.5 mm, 34 days post hatch (dph); B, 1 mm, 43 dph; C, 2 mm, 51 dph; D, 3 mm, 66 dph; E, 4 mm, 71 dph; F, 5 mm, 80 dph; and G, 9 mm, 90 dph.

Table 1. Mean spat weight (g), spat dorsoventral measurement (DVM ± standard error (SE), mm) and volume of 1000 spat (mL) of Saccostrea lineage J spat from 31 to 93 days post hatch (dph), for each spat grade mesh size (mm) and nursery system.

Grade size (mm)	Nursery system	Mean spat weight (g)	Mean spat DVM ± SE (mm)	Mean volume of 1000 spat (mL)
0.5	Downweller	0.003	1.79 ± 0.06	0.42
	Upweller	0.002	1.95 ± 0.05	0.44
1	Downweller	0.006	3.25 ± 0.04	0.83
	Upweller	0.005	3.20 ± 0.04	0.87
2	Downweller	0.013	4.78 ± 0.09	3.78
	Upweller	0.012	4.89 ± 0.09	3.52
3	Downweller	0.025	5.26 ± 0.08	6.97
	Upweller	0.021	5.16 ± 0.08	5.98
4	Downweller	0.053	6.96 ± 0.07	10.54
	Upweller	0.049	7.15 ± 0.08	10.11
5	Downweller	0.126	9.61 ± 0.13	37.35
	Upweller	0.131	9.48 ± 0.15	41.44
9	Downweller	0.381	12.41 ± 0.18	199.18
	Upweller	0.395	13.46 ± 0.25	234.18