Bird strikes have long been a significant concern for aviation safety. Since the first recorded bird strike by an aircraft in 1903, the problem has only grown with the expansion of both air travel and wildlife populations. Each year, wildlife strikes cost the U.S. civil aviation industry millions in damages and downtime, not to mention the potential risk to human life. But what if there was a safe, effective way to keep birds away from airport runways and airspace without causing them harm? Recent research suggests that lasers might be the answer.
A groundbreaking study conducted by the U.S. Department of Agriculture's National Wildlife Research Center (NWRC) has shed light on the potential of low-to-moderate power, long-wavelength lasers as non-lethal avian repellents. The research, published in 2002, focused on lasers with wavelengths between 630-650 nm and their effectiveness in dispersing problematic bird species under low-light conditions.
Impressive Results in Controlled Experiments
The NWRC team designed controlled, replicated 2-choice experiments with captive birds to test their hypothesis that birds would avoid laser beams or beam spots in low ambient light. The results were striking, especially with Canada geese. In tests involving 6 groups of 4 Canada geese each, the birds exhibited extreme avoidance of laser beams over 80-minute periods, with a remarkable 96% of the geese moving to untreated control areas.
Equally promising results were seen with double-crested cormorants. In field trials, these birds abandoned their night roosts after just 3 nights of laser treatment, with several thousand individuals leaving the area. This suggests that lasers could be particularly effective in managing bird populations that gather in large numbers near airport facilities.
The research wasn't limited to just these species, though. Field trials showed that various waterfowl species (including Canada geese), wading birds, gulls, vultures, and American crows also exhibited avoidance of the laser beam. However, the researchers noted that the response was dependent on both the context and the species, highlighting the need for targeted application of this technology.
Advantages Over Traditional Methods
One of the key findings of the study was that lasers offer significant advantages over traditional avian dispersal tools like pyrotechnics, shotguns, and other methods. The low power levels, directivity, accuracy over distance, and silence of laser devices make them safe and effective alternatives.
Unlike noisy pyrotechnics or potentially dangerous firearms, lasers can be used in a more controlled manner, minimizing disruption to airport operations and reducing the risk of accidental injury. This makes them particularly well-suited for use in and around airport facilities where safety and precision are paramount.
Laser Types and Their Effectiveness
The researchers tested several types of lasers, each with different characteristics and effectiveness:
- A 10-mW, continuous-wave, 633-nm laser (Class III B) was used as a visual repellent for brown-headed cowbirds and European starlings. While effective for some species, it didn't repel these particular birds consistently.
- A 68-mW, continuous-wave, 650-nm laser (Class II) showed more promise. When used to target European starlings and rock doves on perches, and Canada geese and mallards on grass plots, it produced significant avoidance behavior, especially in the geese.
- The Laser Dissuader™, a hand-held 650-nm diode laser, was effective in dispersing various species in field settings.
- The Desman™ Laser, a 5-mW, 633-nm He-Ne laser (Class III B), was successfully used to disperse double-crested cormorants from night roosts.
Notably, these lasers are considered safe for both humans and birds when used properly. The research found no evidence of ocular damage to birds even after direct exposure to these lasers at distances as small as 1 meter.
Species-Specific Responses
One of the most interesting aspects of the research was the variation in responses among different bird species:
- Canada geese showed extreme avoidance, with 96% moving to untreated areas.
- Double-crested cormorants abandoned roosts after just 3 nights of treatment.
- Mallards were dispersed (around 57% on average) but habituated to the beam after approximately 20 minutes.
- Rock doves exhibited avoidance behavior only during the first 5 minutes of 80-minute dispersal periods.
- Brown-headed cowbirds and European starlings were not effectively repelled by the lasers tested.
These varying responses highlight the importance of understanding bird behavior and tailoring the use of lasers to target species. It also suggests that an integrated approach, combining lasers with other bird management techniques, might be necessary for comprehensive control.
Practical Applications for Airports
The research points to several potential applications for laser technology in airport environments:
- Night Roost Dispersal: By treating night roosts with lasers, airports could reduce the number of birds present during early morning takeoffs when bird strikes are more common.
- Runway and Taxiway Clearance: Hand-held laser devices could be used by wildlife management personnel to clear birds from active runway and taxiway areas.
- Automated Systems: Fixed-position laser systems, potentially integrated with radar for bird detection, could provide continuous protection of critical areas.
- Low-Light Operations: The effectiveness of lasers under low-light conditions makes them particularly valuable for dawn, dusk, and night operations when many bird species are active.
Considerations and Limitations
While the research shows great promise for laser technology in bird control, there are several important considerations:
- Light Conditions: The effectiveness of lasers increases with contrast between the beam and ambient light, making them more useful during low-light conditions.
- Habituation: Some species may habituate to laser beams over time, reducing effectiveness.
- Retinal Physiology: A species' sensitivity to specific wavelengths and their ability to adapt to different light conditions affects laser effectiveness.
- Context Dependence: Environmental factors, such as urban vs. rural settings, can influence how birds respond to lasers.
- Safety Precautions: While safe when used properly, lasers can cause eye damage if misused, requiring proper training for operators.
Conclusion
The research on lasers as non-lethal avian repellents represents a significant step forward in airport wildlife management. The results clearly demonstrate that low-to-moderate power, long-wavelength lasers can effectively disperse many problematic bird species with fewer risks and less disruption than traditional methods.
As airports continue to seek safer, more effective ways to manage bird populations and reduce the risk of bird strikes, laser technology offers a promising solution. Hand-held laser devices and automated, fixed-position laser systems could significantly enhance bird management efforts, making air travel safer for everyone.
However, the research also underscores the importance of an integrated approach to bird management. Lasers should be part of a comprehensive strategy that includes habitat modification, monitoring, and other deterrent methods tailored to the specific bird species present at each airport.
With further development and refinement, laser technology could become an essential tool in the ongoing effort to reduce bird-aircraft collisions, protecting both human lives and wildlife populations.