For much of their existence, nightjar eggs rely on their parents' camouflage, as the adults sit on the nest. However, eggs are still under pressure to be camouflaged. When the adult flushes to distract predators (or to save its own skin), the eggs are exposed and at high risk of being eaten. Unlike the adults, the eggs are immobile and cannot run away. It is therefore important that they remain concealed through their own camouflage.
Nightjar eggs vary in their level of camouflage. For example, the fiery-necked nightjar shows little camouflage with its plain, pale brown eggs, while the Mozambique nightjar shows background matching and cryptic patterning.