Nocturnal birds have eyes optimised for visual sensitivity, with large corneas relative to the eye's length, which allows them to see well in low light conditions.
These birds have evolved unique visual adaptations to navigate and hunt in low-light environments, making them experts in night vision.
Frigatebirds: Frigatebirds are nocturnal seabirds with large eyes and a high density of rod cells, which helps them see in low light conditions while flying over the ocean at night.
Penguins: Penguins have a visual pigment that absorbs at wavelengths near 543 nm, which is an adaptation to their blue aquatic environment and helps them see in low light conditions.
Nightjars: Nightjars are nocturnal birds with large eyes and a high density of rod cells, allowing them to see in low-light conditions.
Owls: Owls have tubular eyes, and low numbers of colour detectors, but a high density of rod cells, which function well in poor light, making them expert nocturnal hunters.
Stone curlew: Stone-curlews, sometimes known as thick-knees, are busy at night, searching for food with their wide yellow, reptile-like eyes.
Kakapos: Kakapos, endemic to New Zealand, are not only nocturnal but also flightless and ground-dwelling.
Woodcock: Woodcocks are primarily nocturnal, spending much of the day sleeping in deep foliage. They are huge wading birds with a long, straight beak.