Every year, millions of people around the world celebrate the arrival of the new year with dazzling displays of fireworks.
But while these colorful explosions may bring joy and excitement to humans, they can have a devastating impact on the millions of birds that share the sky with them.
According to a recent study by researchers from the University of Amsterdam for Ornithology, fireworks cause massive and widespread flight movements of birds, especially waterbirds, that can last up to 45 minutes.
These movements are not only stressful and disorienting for the birds, but also costly in terms of energy and time.
Fireworks trigger flight responses in birds
The researchers used data from 13 weather radars in Europe and the US to monitor the movements of birds during the night of New Year's Eve from 2014 to 2019.
They found that the number of birds in the air increased by an average of 7.5 times during the fireworks, reaching up to 20 times in some areas.
The birds were mainly waterbirds, such as ducks, geese, and swans, that roost in large flocks near lakes, rivers, and wetlands.
The researchers believed that these birds are more sensitive to noise and light pollution than other birds, and that they may perceive fireworks as a threat and flee to safer areas.
The flight movements of the birds were not random, but rather directed away from the areas with the highest fireworks activity.
According to estimates, birds flew at speeds of up to 60 km/h and at altitudes of up to 1,500 m, which are much higher than their normal flight behavior.
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Fireworks waste precious energy and time for birds
The researchers calculated that the birds burned an extra 3.5 million kilocalories of energy during the fireworks, which is equivalent to the daily energy expenditure of 5,000 flying birds.
This energy loss is significant, especially in winter, when food resources are scarce and birds need to conserve their body fat to survive the cold.
Moreover, the fireworks disrupted the normal sleep patterns of the birds, which are essential for their health and well-being.
The researchers found that the birds spent 40 minutes less time roosting during the night of New Year's Eve, and that they did not resume their normal roosting behavior until 40 minutes after sunrise the next day.
The researchers warned that these effects of firekworks on birds could have long-term consequences for their survival and reproduction, as well as for the functioning of the ecosystems they inhabit.
Reucing the use of fireworks or switching to quieter and less bright alternatives, could help mitigate the harm to our feathered friends.
Fireworks also affect other wildlife and pets
The study focused on waterbirds, but other types of birds and wildlife may also suffer from the effects of fireworks.
For example, a study from the University of Amsterdam showed that fireworks caused erratic flight movements of thousands of birds in the Netherlands.
Another study from the Netherlands Institute of Ecology found that fireworks increased the stress levels of roe deer and badgers.
Fireworks can also pose a threat to pets, such as dogs and cats, that may be frightened by the loud noises and flashes of light.
According to the Animal Advocates of South Central Pennsylvania, fireworks can cause pets to run away, injure themselves, or develop anxiety and phobias.
They recommend that pet owners keep their animals indoors, provide them with a safe and comfortable place to hide, and play soothing music or white noise to mask the sound of fireworks.
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