In order to prevent the bird from being "reckless", do this now

Birds are the most common "animal neighbors" of people in cities. As an important part of the ecosystem, the well-being of birds reflects the state of the city's ecological environment.

The golden autumn season is the migration season when migratory birds spread their wings and fly across thousands of mountains and rivers.

Northern Redstart, a winter migratory bird in Nanjing

In addition to dealing with natural challenges such as disorientation, bad weather, food shortages, attacks by predators, etc., migratory birds also face threats from human society: although transparent glass windows provide humans with a broad view, they mislead birds and insects.

What is a bird strike?

Bird strikes refer to the phenomenon that birds collide with man-made objects during flight, resulting in casualties. During the day, the transparency and reflective properties of glass make birds mistakenly believe that the reflected blue sky, tree shadows, and flowers are real paths. This illusion makes birds mistakenly believe that there are no obstacles ahead and rush towards the glass without hesitation. Once a bird has an illusion and flies towards the glass curtain wall, the result is likely to be death or injury.

A white-crowned bulbul that died from a bird strike. The picture comes from the Internet.

Many migratory birds choose to fly at night to avoid predators and high temperatures. However, when night falls and the lights come on, many migratory birds lose their way in the city lights. Birds lost in the lights often collide with buildings or die of exhaustion because they cannot find a suitable place to stay. In the final analysis, the main reason for bird strikes is that birds cannot see glass.

How to prevent bird strikes?

Birds are an indispensable part of the ecosystem, playing an important role in maintaining ecological balance, controlling pests, pollination, and seed dispersal. The frequent occurrence of bird strikes not only means the loss of biodiversity, but may also affect the health and stability of the ecosystem.

To prevent bird strikes, the first thing we need to do is to make the bird aware that it is glass. Because in many cases, when a bird strikes it, it thinks it is transparent and can pass through. Or, because the glass reflects light, the bird can see the sky or vegetation outside, so it will continue to fly past. In this case, the glass must be treated in a certain way.

The picture comes from the Internet

Using bird strike prevention stickers can effectively reduce bird strike accidents. Stickers need to reach a certain size, density and coverage to effectively reduce bird strikes. * (Tips: Stickers with a spacing of 5cm×5cm are more effective. In terms of color, colors that contrast sharply with the glass, including black and white, will be more effective. In addition, separate orange and red have better bird strike prevention effects. Stickers should be affixed to the outside of the glass to be more effective.) * In this way, for birds, many birds think that they can't fly over, and there is a high probability that bird strikes can be reduced. At night, we can turn off the indoor lights when not needed, or draw the curtains when working overtime after dark, or even just dim the lights or draw the curtains during the migration season (spring migration: March to May, autumn migration: September to November) to significantly reduce the frequency of bird strikes.

Preventing bird strikes and insect traps starts with us

Gray-headed woodpecker killed by bird strike

This year, we found a gray-headed green woodpecker that died from a bird strike on the terrace of our office building, and we took action. In addition to immediately analyzing the bird strike, we also conducted a detailed inspection of the environment around the building. "Bird strike" corresponds to "insect trap". The misleading effect of the building's glass surface reflecting the surrounding environment not only increases the incidence of bird strikes, but also puts many diurnal insects in the predicament of "insect trap". Our attention to the "insect trap" phenomenon in office buildings began in early July 2024. We found dead bees on the ground of the terrace of the office building. After identification, they included rare bees such as folded-winged bees and leaf-cutting bees, which are relatively rare in urban areas. This phenomenon is not a natural phenomenon.

After observation, we found that most of the recorded insect species were flower-visiting insects. It is speculated that flower-visiting insects rely on visual navigation and are attracted by the image on the glass surface to fly into the terrace. After hitting the wall, they are affected by the bright light through the top glass and mistakenly think that the top is the exit and try to fly upwards. However, due to the inverted structure above the terrace, it is difficult for the insects to fly away.

We also realized that working overtime at night without drawing the curtains is also one of the reasons for insect trapping. In order to solve the problem of glass causing trouble to birds and insects, we conducted a pilot project in the areas where bird strikes and insect traps occurred in office buildings. We pasted anti-bird strike stickers and anti-insect matte film stickers that met the size and pattern requirements on the glass surfaces of high-incidence areas.

We enlarged some stickers that we had previously used in native species conservation areas and combined them with dot patterns, which would both prevent bird strikes and look good. This was our first step.

Stick bird-proof stickers on glass

With the cooperation of volunteers, we completed the work of installing anti-bird-strike stickers in the office building area.

After sticking the matte film on the areas where insects are trapped, we are still monitoring the effectiveness of the sticker. At the same time, when it gets dark, we turn on the lights and draw the curtains to reduce the occurrence of bird strikes and insect traps.

If you have observed similar phenomena around you, you can also take action by drawing the curtains or sticking some pattern stickers or matte films on the windows of your home.

Small changes can save lives. Our homes should also be bird-friendly. As for the issue of bird strikes, we also need everyone's efforts. We can also pay more attention to buildings that are prone to bird strikes in our daily lives and participate in data collection.