Table 3. Environmental conditions during trials investigating the effect of crowding on Atlantic mackerel physiology and survival (values indicate means ± 95% CIs unless otherwise indicated).
| Pre-treatment | During treatment | |||||
|---|---|---|---|---|---|---|
| Period | Trial name | Treatment date | Oxygen concentration (mg/l) | Temperature (°C) | Oxygen concentration (mg/l) | Oxygen minimum (mg/l) |
| May/June | Control 1 | 21 May 2019 | 10.096 ± 0.007 | 11.608 ± 0.007 | 10.247 ± 0.004 | 9.26 |
| Control 2 | 28 May 2019 | 9.893 ± 0.002a | 10.991 ± 0.003 | data missing | 9.81 | |
| High and prolonged 1 | 22 May 2019 | 10.952 ± 0.003a | 12.257 ± 0.009 | 9.339 ± 0.012b | 8.71 | |
| Low | 29 May 2019 | 9.877 ± 0.002 | data missing | data missing | data missing | |
| High and prolonged 2 | 6 June 2019 | 9.616 ± 0.001 | 13.880 ± 0.024 | 9.080 ± 0.016b | 7.39 | |
| August/September | Control 3 | 21 August 2019 | 8.356 ± 0.002 | 16.425 ± 0.001 | 8.386 ± 0.001 | 8.37 |
| Moderate | 22 August 2019 | 7.863 ± 0.005 | 16.067 ± 0.002 | 6.182 ± 0.014b | 5.21 | |
| High | 28 August 2019 | 8.241 ± 0.007 | 17.883 ± 0.002 | 6.781 ± 0.028b | 5.22 | |
§
aMeasured <1.5 hours after treatment period.
bSignificantly different (P < 0.05, GLS modelling with Wald F testing) during treatment from both pre-treatment levels and the corresponding control trial.