Birds can collide with manmade objects and this can happen very often. The question that always intrigued the scientists is why? Since it was accepted by everyone that birds use their sight as the first of their senses when they fly, it was a mystery why they could not see the obstacles in their way. The most unpleasant thing is that collisions with pylons, turbines and power lines lead to 25% of the juvenile and 6% of the adults’ deaths of endangered species like Ciconia ciconia (or the White Stork).
People have tried to understand the reason behind these accidents and also sought to find a way to warn the birds of the danger. They failed on the most part because, until now, they also tried to make the obstacles more noticeable for human eyes and not for the birds.
Studying their way of flying, scientists have come to two relevant conclusions: one, that birds don’t always look forward when they fly, most of the times they look for prey or interesting places on the soil, so their binocular vision makes them practically blind for the obstacles ahead; and two, that birds usually can’t adjust too much the speed at which they’re flying, so at high speed and in poor weather conditions, they are not able to adjust to the changes they encounter in their path. It also seems that birds are more attuned to the direction they are flying and don’t use their sight to look into open space. It mostly seems that they are guided by their instinct to maintain the right course, and not by their eyes.
The best method to help the birds and prevent accidents, is to make them aware of the danger through alerting sounds and signals that should be placed at some distance from the obstacle to give them time to adjust their direction.