Many species of birds are active primarily during the night, a behavior known as nocturnality. Nocturnal birds have adapted physically and behaviorally to thrive in darkness. Here are some of the most common nocturnal bird species.
Owls
Owls are among the most iconic nocturnal birds. Their large, forward-facing eyes and exceptional hearing give them excellent night vision and prey detection abilities. Some owl species, like the Barn Owl, are strictly nocturnal. Others, like the Great Horned Owl, are crepuscular – active at dawn and dusk.
Some of the most common nocturnal owl species in North America include:
- Barn Owl
- Barred Owl
- Great Horned Owl
- Eastern Screech-Owl
- Northern Saw-whet Owl
Nightjars
Nightjars are a family of nocturnal birds including nighthawks, whip-poor-wills, and poorwills. They have cryptic plumage, large eyes, and large mouths to facilitate nighttime feeding on flying insects. Their name comes from their loud, jarring calls.
Some common nightjar species include:
- Common Nighthawk
- Chuck-will’s-widow
- Common Poorwill
- Eastern Whip-poor-will
Seabirds
Many seabird species are nocturnal or crepuscular when visiting their breeding colonies, avoiding aerial predators. These include shearwaters, storm petrels, diving petrels, and some albatrosses and penguins. Nocturnal behavior in seabirds may also facilitate prey capture.
Some nocturnally-active seabirds include:
- Manx Shearwater
- European Storm Petrel
- Ancient Murrelet
- Cassin’s Auklet
- Magellanic Penguin
Wading Birds
Some wading bird species forage nocturnally, including bitterns, herons, and egrets. These tactile foragers use their long bills to hunt prey in shallow water under the cover of darkness. This may help avoid competition and increase foraging success.
Some primarily nocturnal wading birds are:
- American Bittern
- Black-crowned Night Heron
- Yellow-crowned Night Heron
- Great Blue Heron
Shorebirds
Many shorebirds migrate long distances at night. Some reasons include avoiding overheating in daytime, using stellar and magnetic navigation cues, and avoiding predators. Shorebirds that regularly migrate at night include plovers, sandpipers, snipes, curlews, and phalaropes.
Examples of nocturnally migrating shorebirds:
- Wilson’s Snipe
- Spotted Sandpiper
- Whimbrel
- Ruddy Turnstone
- Red-necked Phalarope
Other Nocturnal Species
Some other birds exhibit nocturnal behavior, including:
- Pauraques – nightjars that perch lengthwise on branches.
- Bitterns – wading birds that stand motionless in wetlands to ambush prey.
- Northern Hawk Owl – the only diurnal North American owl, sometimes active at night.
- Rails – wetland birds that sneak through dense vegetation at night.
Advantages of Nocturnality in Birds
Being active at night provides many potential advantages for birds:
- Avoiding daytime predators like raptors and crows
- Reduced competition for prey at night
- Lower ambient temperatures at night help reduce heat stress
- Enhanced cryptic and camouflage effects in darkness
- Prey may be more active and vulnerable at night
- Cover of darkness aids stealth and surprise attacks
- Nocturnal migration may allow use of celestial navigation
Physical Adaptations for Nighttime Activity
Birds exhibit many physical adaptations that facilitate nighttime activity and survival, including:
- Enlarged, tubular eyes – Increase light gathering and enhance vision in low light.
- Owls have massive eyes – Barn Owl eyes are more than double the size of human eyes.
- Large corneas and pupils – Allow more light into the eye.
- Rod-dominated retina – Rod cells are more sensitive to low light than cone (color-sensing) cells.
- Binocular vision – Having both eyes face forward increases depth perception at night.
- Long, hooked bills – Help locate prey by touch in murky water.
- Soft plumage – Allows silent, stealthy flight to aid nocturnal hunting.
Behavioral Adaptations
In addition to physical adaptations, nocturnal birds exhibit behavioral changes that promote nighttime success:
- Excellent hearing – Detect faint sounds to locate hidden night prey.
- Vocal modifications – Some night bird calls are lower pitch to avoid revealing locations.
- Cryptic roosting spots – Hide in vegetation or crevices during the day to avoid predators.
- Crepuscular activity – Active during twilight periods to transition between day and night.
- Reverse sleep cycle – Sleep during the day rather than at night.
- Winter roosting – Some species gather in large communal roosts at night in winter for warmth.
Threats Facing Nocturnal Birds
Although the darkness provides benefits, nighttime activity also poses risks for birds. Some key threats include:
- Predators – Owls, foxes, raccoons, cats, and snakes hunt nocturnal birds.
- Habitat loss – Especially loss of wetland and old-growth forest habitats.
- Disorientation – Artificial night lighting can confuse and disrupt navigation.
- Collisions – Window and building collisions are a major hazard.
- Light pollution – Alters predator-prey dynamics and causes physiological disruption.
Unique Adaptations of Owls for Nocturnality
Among birds, owls exhibit some of the most specialized adaptations for seeing and hunting in darkness:
- Discs around eyes – Condense and focus faint light.
- Asymmetrical ear placement – Precisely localizes prey rustlings and squeaks.
- Silent flight feathers – Serrated edges break up air turbulence.
- Excellent spatial memory – Remembers nest sites and hunting areas.
- Reversible outer toe – Helps owls grasp and manipulate prey effectively.
- Acute low-frequency hearing – Detects subtle prey movements in vegetation.
Conclusion
A wide variety of bird species have adapted to exploit the nighttime environment through specialized eyesight, stealth, navigation, and hunting strategies. However, nocturnal birds face risks including predators, habitat loss, disorientation, and collisions. Protecting nocturnal birds requires conserving habitats while minimizing artificial night lighting near key foraging and roosting areas.