Effect of Temperature on Development of Mallee Fowl Leipoa ocellata Eggs

Mallee fowl eggs were successfully incubated over the temperature range 32-38 C. Greatest hatchability occurred at 34 C (80%); 22% hatched at 32 C, 44% at 36 C; and 38% at 38 C. Field data indicate that eggs can tolerate temperatures as low as 28 C for at least 4 days and that egg temperature can vary from 28 to 38 C during incubation. Birds did not regulate mound temperature as precisely as previously reported, 3-5 C variations in temperature were common. Energetic cost of development was found to be temperature dependent. Embryos developing at 32 C required 74% more energy than embryos developing at 38 C.