Reproduction and embryo viability of a range-limited tropical freshwater fish exposed to fluctuating hypoxia

摘要: Hypoxia can profoundly affect fish reproduction and larval development, but its effects on from tropical Australia are not well understood. In the present study, of diel fluctuating hypoxia embryo viability were investigated for a range-limited freshwater fish, namely Utchee Creek rainbowfish (Melanotaenia utcheensis). The lethal level adult after gradual oxygen depletion was ~7% dissolved (DO) saturation. After 28 days, reproductive success exposed to treatments measured by fecundity, gonad health, egg incubation time, mortality, size hatching larvae. Reproduction impaired in lowest sublethal treatment (minimum 10% DO saturation each day). No ill parental exposure embryos identified, minor differences temperature between aquaria had greater effect than treatments. Similarly, no embryonic identified. appear be more tolerant temperate species, keeping with their habitat warm lowland streams, they still susceptible increasing frequency intensity possible reduced flow as result climate change.