What temperature does a bird egg die at?

Bird eggs are highly susceptible to temperature changes, and the exact temperature at which an egg dies can vary depending on the bird species and the stage of development of the egg. Generally, however, bird eggs are most sensitive to temperature during the early stages of development, and a drop in temperature below about 80 degrees Fahrenheit (27 degrees Celsius) can be lethal. Prolonged exposure to temperatures above 104 degrees Fahrenheit (40 degrees Celsius) can also be fatal.