Sensitivity of striped trumpeter, Latris lineata, embryos to mechanical shock and simulated transport

The sensitivity of striped trumpeter, Latris lineata, embryos to transport was assessed through mechanical shock at four stages of embryonic development, and simulated transport at different densities and durations. Fertilised egg mortality due to mechanical shock was greatest for embryos shocked 3 and 27 h post-fertilisation (48.6% ± 4.1 and 36.0% ± 3.2, respectively; mean ± SE), and prior to blastopore closure. Mortality of embryos shocked 51 and 75 h post-fertilisation, and following blastopore closure, did not differ from un-shocked controls (9.5% ± 0.7). Density and duration of incubation affected the survival of embryos in a simulated transport trial. Embryonic mortality remained below 3% for all density treatments up to 24 h post-fertilisation. Significant mortality of fertilised eggs occurred when incubated at 5,000 embryos l⁻¹ (17.2% ± 6.9) for 48 h and was correlated with a drop in dissolved oxygen (DO) levels. Final DO concentrations decreased with increasing embryonic density and incubation duration. DO of embryos incubated at 5,000 embryos l⁻¹ was significantly lower than those incubated at 500, 1,000 and 2,500 embryos l⁻¹, at all incubation durations. Mortality was prevalent in treatments that had a final DO level less than 72% saturation at 14°C. Transportation of fertilised striped trumpeter eggs in seawater is recommended from 51 h post-fertilisation at 14°C, after blastopore closure and neural keel development and at densities of no more than 2,500 embryos l⁻¹ for 24 h transportation duration.