Birds can become stunned for varying lengths of time after hitting a window. The severity of the impact, the size and species of the bird, and other factors all contribute to how long a bird may remain dazed or unconscious after a collision.
What causes birds to become stunned after window strikes?
When birds fly into windows, the impact can cause trauma to their bodies and brains that results in stunning or knock out effects. Some of the potential causes of stunning include:
- Concussion or other head trauma from the force of the blow against the window.
- Temporary damage or disruption to brain function.
- Disorientation and confusion from striking an unexpected barrier.
- Physical injury that causes shock or loss of consciousness.
- Stress response that causes temporary freezing or inaction.
The speed at which a bird is flying and the angle at which it hits the window will influence the severity of the impact and stunning. Head-on collisions have greater stunning potential than glancing blows.
Factors that influence duration of stunning
Some key factors that can influence how long a bird remains stunned after hitting a window include:
Extent of injury and trauma
More extensive concussions or other injuries from major impact will lead to longer periods of being stunned. Severe head trauma can potentially lead to death either immediately or later after a collision. Minor impacts may only cause brief disorientation for a few seconds or minutes.
Size of the bird
Larger birds with more body mass have greater momentum when flying and therefore greater collision impact forces with windows. This means larger birds are likely to suffer more traumatic impacts that lead to longer stunning times. Smaller birds don’t build up as much momentum and may have shorter stunning periods.
Type of bird
Some bird species may be more susceptible to traumatic impacts than others based on anatomy. Birds with larger heads relative to body size may be at higher risk of concussion. Migratory birds that fly greater distances at higher speeds may also suffer more damaging window collisions. Different species can vary in their recovery times.
Age and health of the bird
Younger birds and weaker individuals in poor health will typically be more vulnerable to traumatic injuries and require longer recovery periods. Older birds may also take longer to regain normal function after major impacts. Robust, healthy birds in their prime may bounce back more quickly.
Prior collisions
Previous window strikes can weaken a bird and make subsequent collisions more dangerous. Multiple collisions in a short time span can have cumulative effects and prolong stunning. First-time strikes generally have shorter periods of incapacitation.
Weather conditions
Poor weather visibility during storms or high winds can cause birds to fly more erratically and strike windows with greater force, amplifying trauma. Colder temperatures may also slow recovery. Mild weather generally means less kinetic impact against glass.
Duration examples of bird stunning
To illustrate how long stunning can last, here are some examples based on factors like injury severity and species:
Bird Type | Injury Severity | Stunning Duration |
---|---|---|
Small songbird like a chickadee | Mild concussion | 15-30 minutes |
American robin | Moderate head trauma | 1-3 hours |
Mourning dove | Severe brain injury | Over 3 hours or permanent |
Bald eagle | Major collision impact | Up to 12-24 hours |
As these examples show, larger birds and more forceful impacts that cause greater trauma are likely to result in longer periods of incapacitation, sometimes lasting for many hours or even resulting in death after extensive injuries.
Signs of concussion in birds after window collisions
Some symptoms that point to concussion and stunning in birds after window strikes include:
- Unconsciousness or semi-conscious, dazed state
- Inability to fly or walk properly
- Disorientation, confusion
- Dilated pupils
- Unresponsiveness to stimuli
- Holding head in an unusual position
- Seizures or tremors
- Loss of balance or coordination
The longer these signs persist, the more severe the head trauma is likely to be. Birds recovering from minor collisions may exhibit just brief disorientation for under an hour before flying away.
Treatment for window-stunned birds
If you find a bird dazed after hitting a window, here are some tips for treatment and care:
- Gently place the bird in a ventilated box lined with a soft cloth for support and transport.
- Keep the bird in a quiet, warm, dark place to allow recovery.
- Don’t try to give food/water until fully alert.
- Monitor breathing and watch for return of alertness and ability to perch/move.
- Once recovered, release the bird outdoors close to where found.
- If injuries seem severe or recovery takes more than a few hours, contact a wildlife rehabilitator for assessment.
With appropriate care and monitoring, many concussed birds can fully regain normal function after window collisions. However, severely injured birds may need specialized rehab. Quick, careful response improves recovery outlook.
Preventing bird-window impacts
To help minimize collisions that stun birds, some deterrent options include:
- Applying decals or tape strips to windows to make glass more visible.
- Installing screens over window exteriors.
- Using UV-reflective, patterned or fritted glass treatments.
- Keeping exterior lights turned off at night.
- Reducing vegetation and feeders near windows.
- Training house pets to minimize activity near windows.
Following bird-friendly building design guidelines can also help reduce risky conditions that contribute to window strikes.
Conclusion
Birds can become stunned for widely variable lengths of time after colliding with windows. Mild impacts may only daze birds for minutes, while severe collisions can cause concussions leaving birds incapacitated for hours or longer. Larger birds and direct blows at higher speeds typically cause more traumatic injuries and extended recovery periods. With proper treatment, most concussed birds can fully regain function after window collisions, but preventing such strikes in the first place is the best approach for bird safety.