Adaptation of the text: 20 things that (maybe) you do not know about the Bird of the Year, the Barn owl. Published in 02/01/2018 by SEO/BirdLife and translated by Kátia Boroni for www.facebook.com/corujandoporai.
The bird of the year: The Barn Owl
The barn owl (Tyto alba) is the 2018 Bird of the Year. It was chosen by participants in the popular vote organized by SEO / BirdLife - Spain. During 2018, the environmental NGO will carry out actions of awareness and conservation about this species that, in the last decade, lost 13% of its specimens. In some parts of the peninsula (Spain), in fact, the fall comes to 50%. Although known among the public, today the bird of the year still maintains secrecy and curiosities. These are 22 things that (maybe) you did not know about it.
How big it it? Between 32 and 40 centimeters in height. More or less what a newspaper measures in Spain.
How much does it weigh? About half a pound, between 430 and 620 grams. (Note: In Brazil the barn owls are of the subspecies Tyto furcata, and are smaller than the European Tyto alba. A barn owl in Brazil hardly exceeds 500 grams). In the US there are the Tyto furcata, known also as American barn owl, and is also bigger than the Brazilian one.
Where can you observe it? The barn owl covers most of the world. It is only missing in very cold regions (for example, the Arctic) and in the desert or in excessively arid climate. It is also not seen on some Pacific islands, in most of Indonesia or in the northern Himalayas. It is present in Europe, except in Scandinavia and Iceland. In fact, it is the only species of the family Tytonidae present in Europe.
Are all owls the same? Owls make up a family of birds, the Tytonidae, with few species (about 16). Of all the species, the most abundant is the barn owl or Tyto alba, but attention, there are described 46 subspecies of Tyto alba, and some are candidates to become species because they have significant differences.
How many types of owl are there in Spain? Of course, the most widespread subspecies in Spain is Tyto alba, the barn owl (known in Brazil as Suindara), present throughout the peninsula, in the Balearic Islands, Ceuta and Melilla, and in the western of Canary Islands. The subspecies gracilirostris - the owl majorera - is present in Fuerteventura, Lanzarote and Alegranza. Finally you can see the guttata subspecies, darker, which generally behaves like wintering and comes from the east and center of Europe.
Are all owls from the same family? There are several words in Spanish to name owls, and they cause confusion even among native speakers: búhos, lechuzas, mochuelos, autillos, cárabos. All the owls belong to the same order of birds, the Strigiformes or nocturnal birds of prey. This order is divided into two families, the tytonidae (barn owls) and the Strigidae, which encompasses the rest of the species. So the búhos and lechuzas are from different families, in Portuguese and in English we use only one word for these birds: corujas in Portuguese and owls in English.
In the movie Harry Potter they used owls of several species, among them the barn owl. Harry Potter´s owl, Hedwig, is a snowy owl (Bubo scandiacus).
And how do barn owls differ from others? It depends on the species. If we speak of the Eagle owl (Bubo bubo), the most common in the peninsula (Spain), the fundamental differences are in the eyes - yellow in the case of the eagle owl, and black in the case of the barn owl - since the eagle-owl is much larger than the barn owls. The eagle owl does not have a facial disc so marked and has feathers on both sides of the head (called tufts). By the way, even if it looks like, these feathers are not ears.
How do barn owls hear? Owls are known for their prodigious sense of hearing, and possess a characteristic element called the facial disc. In addition to performing the typical functions of a face, the disc acts as a sort of satellite dish that captures and distributes the sound to its two ears, conveniently hidden on both sides of the face, but at different heights, thus allowing a better location of the prey. Thus, the owl's face is a large satellite dish.
(*) The owl has its ears at different heights. In this way, and in combination with its facial disc, the owl is able to triangulate the position of something, depending on the sound. This phenomenon is called an eco-location.
How do owls see? Unlike most birds, the owl's eyes are in the frontal position: they can calculate depth and observe the reality in three dimensions. To see laterally, the neck allows it to turn the head 180 degrees on each side. The owls´ vision is almost twice as sensitive to light as that of the human being, and it perceives everything that moves, so to confuse it, it is best to be completely still. Its eyes also work well in daylight, but sudden flashes - for example, of cars - can blind its vision momentarily.
How do owls fly? In silence. Their feathers have a special structure that allows the friction with the air to be reduced. So they can play with the surprise effect when it comes to hunting. They are also experts on slow flights, which allow them to locate their prey better.
How do owls eat? They are carnivorous and usually feed on small mammals, such as mice or rats. That is why, in many European countries, they are considered allies of farmers. In fact, there are actual real networks of nest boxes and perches to allow owls to eat the rats that feed on the crops. There are even barns adapted for them to make their nests. They swallow their prey completely, but do not digest the skin, the hair or the bones. This type of residue is later regurgitated in a ball known as pellet. If you find a kind of black ball with bones, there is an owl in the area.
How do owls sleep? Like all birds of prey, standing on their claws. They usually do this logically during the day. They are more active at sunrise and sunset.
Do owls migrate? The owls residents in Spain do not, although in winter there are the arrival of European owls. In any case, and in general, barn owls are sedentary and very cosmopolitan. It is not by chance that they are called barn owls or church owls, since these are places where they like to shelter and breed.
Where do they live? Owls live in territories that, in winter, reach about 5,000 hectares (or about 7,000 football fields). In summer, they generally reduce to 350 hectares. It's always the same. At the very least, each action area has a nest, a couple of places to sleep and an undetermined number of places to visit occasionally. Territories are not necessarily circular, they can take almost all forms, and while they spend their entire lives in them, owls study them: they memorize the best places to hunt, the best flight routes, the best place to nest.
Where do they nest? They do not build nests. They take advantage of all types of cavities, located mainly in rural buildings. That's why they're called barn owls, or, in Portuguese, church owls. It is not that they have love for these two types of buildings, but these places provide them with what they need: a refuge where they feel safe and protected from rain and wind, and because they are tall. Owls usually prefer places at least three feet above the ground.
What climate do they prefer? They are sedentary and they adapt to climatic variations. It is in the winter that they are in danger because of the scarcity of food and due to their need for more energy. Too much rain does not suit them, especially during the breeding season. Like so many other species, the extreme weather events that global warming brings impact their survival. Because their feathers are very soft, they are not impervious to rain, and periods with heavy, intermittent rains can make them unable to hunt and starve to death. As they also have accelerated metabolism, in the cold they need to feed more, and because they have a more restricted diet than other species (preferably rodents), their survival rate in winter decreases a lot.
How long do they live? It is estimated that the average is four years, but the fact is that there are records of owls with 15, 17 and up to 25 years of age. This short average is due to the fact that mortality in the first year is big and people don’t not make things easier.
Are the owls faithful? They are incredibly faithful to their partner and the territory where they settle (depending on the circumstances, of course). This does not mean that they do not share an area with other couples or individuals. They are generally not very territorial. (???)
Can you distinguish males and females? The most distinctive element is that most females have small brown spots on the chest, while males usually have a completely white chest. In Brazil the barn owls have a darker color, yet females generally have a darker golden chest, and males have a whiter chest, but both have dark spots.
How is its singing? In fact, they manifest a wide variety of vocalizations (17 types have already been recorded), almost all strident. The loudest sound is a loud, metallic chirp, which increases as the owl emits it. The truth is that it's perfect for a horror movie. Because of this “scream”, characteristic of Tytonidae owls, many believe they attract death, and this causes the death of many owls all over the world.
Why is the barn owl associated with all kinds of legends? These poor owls are associated with both positive and negative things at the same time. Because they have nocturnal habits and a sound that sounds like a human scream, they are believed to bring a bad omen and even death. But they are also associated since ancient times to wisdom and knowledge.
How many are there? It is difficult to know for certain because of their nocturnal habits, so the population size is just estimated. There is only one estimate for Spain, made in the 90's of last century and that suggested a population between 50,400 and 90,500 individuals. The European population, according to BirdLife International, has been estimated at between 111,000 and 230,000 and represents about 5% of the world's population. Regardless of the exact number, trends point to population declines.
References
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