Animals bewildered and sudden change of weather: what will happen during the eclipse?

BarcelonaThe total solar eclipse on August 12 will be historic, in our region. It is an exceptional phenomenon that, for the vast majority of the population, is only seen once in a lifetime without having to travel halfway around the world. For a few moments, in one part of the country, day will turn into night, the landscape will adopt an unusual light, and the sky will offer a unique spectacle that has awakened fascination, questions, and legends since time immemorial.

Beyond its extraordinary beauty, the totality phase of the eclipse causes changes that surprise scientists and any observer alike. The sudden disappearance of sunlight alters the environment instantly: the temperature drops in a few minutes, the landscape colors transform, and the atmosphere acquires a stillness difficult to describe in words.

Nature also reacts to this unexpected twilight. Many animals, bewildered, interpret the sudden darkness as the arrival of night and modify their behavior. All this turns the eclipse into a large-scale natural experiment, capable of revealing how much life on our planet is synchronized with the Sun's daily cycle.

And, while the Earth is immersed in this ephemeral twilight, the sky shows details that are normally hidden during the day. The Sun's corona unfolds around the darkened disk of the Moon, and some of the brightest planets and stars can be distinguished. A unrepeatable experience that will make this August 12 a date destined to be etched in collective memory.

Sudden darkness and weather change

“The sunlight is so powerful that, when the total solar eclipse occurs, it will suddenly get dark; the change will be abrupt and will have little to do with a slow sunset or sunrise,” explains astrophysicist and science communicator Joan Anton Català.

During the partial phase of the eclipse, the sensation of darkness is practically non-existent, as the Sun continues to illuminate us strongly, even when it is 99% covered. That is why it is not until the Moon completely covers it that, suddenly, night arrives. “It will not be a totally black night, but rather, since there will be sunlight a few kilometers on the horizon, we will see a certain brightness – Català adds–. If we can be in an elevated area, we will see a very striking sight in the landscape: how the Moon's shadow arrives and leaves the horizon suddenly,” he points out.

The protective glasses can only be removed during the totality of the eclipse. It will be then when, according to the astrophysicist, we will witness a true spectacle in the sky. In broad daylight, we will see the brightest stars, such as Vega, Arcturus, or Altair, and, above all, the planet Venus, which will shine brightly in the upper left of the Sun's position, hidden by the Moon. “The solar corona will look very beautiful around the dark disk, and it will also illuminate the sky a little,” assures the expert.

According to Català, the phenomenon will also cause sudden changes in the weather. Among these changes, an ephemeral drop in temperatures stands out, which can reach three or four degrees in a few seconds. Some wind can also pick up and, if there are thin clouds, they can even dissipate due to the sudden change in temperature in the atmosphere.

Català recommends recording the ambient sound at the moment of the eclipse's totality to always remember how we experienced such an extraordinary event. "It's such an exciting moment that you're not aware of what you're saying or the exclamations you're making; collectively, it's a very interesting situation, because we'll all find ourselves connected looking at a unique event, and we'll be very moved," he assures.

This eclipse will take place in the evening, coinciding with sunset, and not in broad daylight, when the impact of the lack of light would be more evident. Will this detract from the event? Català believes not. "I would have chosen for the eclipse to be at noon, but we can't change that, and it also has its positive and interesting side – he states. Since the Sun will be very low on the horizon, we will be able to integrate within the same view of the spectacle a skyline of natural landscapes, people observing the phenomenon, or iconic city buildings with the eclipse as a backdrop," the expert remarks.

The photographs of this day, therefore, can become authentic postcards that will go down in history. But the spectacle will not end there, as at night the Perseid meteor shower, popularly known as the Tears of Saint Lawrence, will reach its peak, a phenomenon that this year will be particularly well seen, as the new moon will guarantee a very dark night sky. In short, August 12th will be an extraordinary day for astronomy.

Confusion among animals

The total eclipse will also have effects on animal behavior. The sudden disappearance of sunlight alters their biological rhythms and causes many species to react as if the day had ended prematurely.

“The most frequent changes observed are those of animals that, during a total eclipse, modify their routine and behavior because they react the same way as when the light goes out in the evening,” explains Jaume Fatjó, ethologist, veterinarian, and director of the Fundació Affinity Animals i Salut chair at the Universitat Autònoma de Barcelona (UAB).

Birds are one of the most obvious examples. “During the totality phase of the eclipse, it is common for them to stop singing and seek shelter, just as they do when dusk arrives,” assures Fatjó, adding that it has sometimes been observed that, when the Sun reappears, “some resume singing as if a new day had begun.” In addition, nocturnal insects may become active. On August 12, the Sun will shine partially again for a few minutes before setting completely after the totality phase of the eclipse, so these situations could occur.

Restlessness has also been described in various species during a total eclipse. “There are animals that show a certain ethological anxiety: they detect that something unexpected is happening in their environment, but they cannot understand the cause – states the ethologist–. Some animals begin to walk from one side to the other restlessly.” This stress caused by an unknown astronomical phenomenon is reminiscent, in a way, of the fear that eclipses used to evoke among humans before science explained their origin.

Zoos have also been the scene of some of the most curious observations during this type of phenomenon. Animals that have internalized the routine of going to sleep when it gets dark react the same way to the sudden darkening of the sky.

“In some zoos it has been observed that animals, when a total eclipse occurs, head to the door of the indoor facility because they think night has arrived and it is time to go to sleep,” adds Fatjó. A behavior similar to what has been observed in farm animals. “If cows have the habit of returning to the stable when it gets dark, during an eclipse they may make this same journey,” remarks the ethologist.

Cats and dogs, not paying much attention to the sky

But the animals that humans have closest to us are domestic ones, especially cats and dogs. The effect of the eclipse is usually very different in their case, as they are used to our rhythm and not depending on sunlight. Experts explain that what most conditions their behavior is not so much the sudden darkness, but the reaction of the humans around them.

“If we take the dog as an example, imagine that it arrives at an unknown place, full of people wearing strange glasses, and suddenly everyone starts shouting and applauding when the totality phase of the eclipse occurs. It is clear that it will get nervous, as human behavior is the stimulus that most influences its behavior,” explains the expert. Therefore, the most advisable thing is to leave companion animals at home, instead of taking them with us to observe the eclipse, as they can be unnecessarily stressed.