Gastrulation and hatch as critical thermal windows for salmonid embryo development

Climate change and impoundment increase river temperatures, shifting the bioclimatic envelope in which freshwater biota have evolved increasing salmonid egg mortality. To mitigate this, conservation flows from reservoirs are often implemented to maintain favourable water temperatures downstream impoundments throughout embryo development. However, as becomes scarcer, there is a need understand requirements of embryos balance these with anthropogenic demands. This study combines laboratory-based modelling approach test effect different on survival fertilisation hatch model species. Further, dropping high optimal conditions at hatch—a perceived period greater sensitivity temperatures—is tested. The shows mortality increases temperature greatest during gastrulation hatch. Also, that experienced had rates hatch, even when were optimal. indicates sublethal developmental abnormalities caused by Therefore, survival, cold resources ideally will target both stages.