What’s the “Material Threat Factor” and How Does It Relate to Birds?
Birds know to stay away from cats, squirrels, and snakes, but they’re vulnerable to less obvious hazards. Clear windows threaten birds because it’s challenging for them to distinguish glass from openings.
Transparent windows are just one example of an object with a high material threat factor. How does the material threat factor relate to birds, and what can you do to protect birds from these threats?
How Does the Material Threat Factor Affect Birds?
The material threat factor measures the risk that building materials impose on birds. Materials with a higher score are more likely to kill or injure birds because they’re difficult to see. Lower scores mean the building is easy for the birds to spot and avoid.
Material threat factor scores come from the American Bird Conservancy (ABC). This Virginia-based nonprofit organization focuses on aiding birds throughout North and South America. In October 2011, the organization published its material threat factor ratings from 0 to 100. With this data, building owners and developers can adjust their facilities and make them safer for birds flying around.
What Materials Have the Highest Threat Factor?
The threat each building poses depends on how risky its materials are. While glass is the most hazardous, it depends on what type of glass you use. The ABC says these three materials have the highest material threat factor:
1. Clear Glass
Clear glass is far and away the most significant threat to birds, with the ABC giving it a 100 threat factor. Birds see clear glass and think there’s an opening to head inside. Unfortunately, the glass is practically invisible to them, thus significantly increasing the chances of collision.
Most birds die instantly after colliding with a clear glass window because of their flying speed. Those surviving the collision often endure severe injuries, such as concussions or broken limbs. While these creatures are intelligent, birds cannot distinguish if there is a barrier between them and what they want to approach.
2. White Ceramic Frits
The second-highest score for material threat factor belongs to white ceramic frits. Some buildings implement ceramic dots or frits on their glass surfaces. While less dangerous than clear glass, white ceramic frits earn 41 points on the material threat factor scale if they have 20% coverage. You can reduce the threat factor to 24 points with 40% coverage, but it still endangers birds.
Light-colored frits are most dangerous for birds when the sun shines bright. They may confuse the frit for a landing spot and injure themselves. If you want to deter bird collisions, it’s best to find a darker material.
3. Coated Glass
Coated glass is the third most dangerous type of glass for birds. The ABC gives it 34 points on the material threat factor list when the manufacturer arranges the ultraviolet (UV) reflective lines in an irregular, web-shaped pattern.
UV rays are invisible to humans, so it’s hard for you to know what other creatures can see. However, birds and other animals can see UV light because of their unique eye construction. While bird eyes transmit UV light, they’re still vulnerable to coated glass because it’s like a mirror to them. Their minds think they have enough space for flying, but it’s dangerous.
What Materials Have the Lowest Threat Factor?
Clear glass is popular for building owners wanting to create a particular aesthetic and introduce natural light into their facility. However, these materials are better choices if they want to reduce the risk for birds:
1. Opaque Materials
Building materials that don’t shine or reflect are the best options for protecting birds in your area. Opaque objects like bricks, stone and wood offer no doubt to birds that this surface is in their way.
These building materials offer no transparency, so nothing behind them can tempt the birds if they can’t see past. Plus, they fit in with a bird’s eyesight, considering there are no visual cues to confuse the bird. Bricks and stones don’t shine like glass does. While some birds build nests inside brick and stone structures, there’s a minimal risk of collision and injury here.
2. Translucent Plastics
Translucent plastics are another excellent choice because the ABC only gives them two points on the material threat factor rankings. Whether single pane or insulated, fiberglass panels pose little risk to birds. These objects have no transparency and won’t tempt curious birds as they fly around. Another option for building owners is installing corrugated fiberglass panels because their ridges deter birds.
3. Specialty Glass Products
While glass is not preferable for deterring birds from your buildings, some types are acceptable because of their low liability. Specialty glass products are adequate for buildings because of their low reflections and temptation for birds.
For example, a translucent channel glass with an orange peel only has 10 points of material threat factor. Another solid option for building owners is a glass block with a grooved textured surface because it only has 10 points. You can also protect birds by incorporating dark-colored frits, such as orange and black fixtures, to deter bird collisions.
How Can You Protect Birds From Buildings?
Colliding with windows, structures and buildings causes nearly 1 billion bird deaths in the United States yearly. How can you protect birds from these accidents? Here are a few suggestions for improving bird health in the U.S. and worldwide:
1. Incorporate Safer Building Materials
New construction is essential for opening new businesses and living spaces across cities. When building new facilities, the architects should account for bird safety. Protecting birds with new construction starts with incorporating safer building materials.
Planners should avoid clear glass due to its adverse impact on local bird populations. Instead, project managers should opt for patterned frames to help the birds’ vision.
Safer building materials apply to more than just houses and office buildings. Researchers have reduced bird deaths in wind turbines by incorporating artificial intelligence and darker blades.
2. Adjust Current Unsafe Structures
Bird protection doesn’t have to come solely from new construction. Retrofitting current structures is another option to save bird lives.
Some adjustments are inexpensive and don’t take long to install. For instance, applying film on the outside of windows deters bird collisions because it increases visibility. Upgrades like dark frits, screens and awnings may take a little longer but are worth the time and effort.
3. Institute Maximum Threat Factors
Cities and states can protect their bird populations by instituting maximum threat factors permitted in new buildings. Some municipalities have already enacted laws to promote conservationism in the area.
For example, New York City’s Local Law 15 of 2020 requires new construction to reduce bird strike fatalities to use bird-friendly materials in the walls, balconies and similar locations. On the state level, you can find bird-friendly legislation in Minnesota, Maryland, Illinois and California.
Protecting Birds From Accidents
While intelligent, birds are prone to accidents like other animals. Millions of birds worldwide die annually because they accidentally fly into buildings and windows.
Humans erected these structures, so it’s only fitting they protect birds by using materials with a low threat factor. Incorporating safer building materials supports bird populations and makes them less vulnerable to extinction.
