Practically any child to the question: “What northern animals do you know?” among others, says — polar owl. This is no coincidence, because the white bird has become so widespread throughout Eurasia and North America that it has become one of the symbols of the north. It is even depicted on the emblems of some circumpolar cities.
Origin of the species and description
The snowy owl, or as many people call it, the white owl, belongs to the genus of owls, the owl family of the owl order. The bird got its second name for its white plumage, distributed throughout the body. In the original classification, this species was included in a separate genus, but modern biologists believe that the snowy owl belongs to the genus of eagle owls.
According to paleontological data, the common ancestor of all owls lived about 80 million years ago. Some species, including probably the snowy owl, became widespread 50 million years before the appearance of man. One of the proofs (but not the only one) of their antiquity is the fact that they are common on disconnected continents, and have the same appearance, although owls themselves never fly across the ocean.
Video: Snowy Owl
The features characteristic of all owls include the fact that they lack eyeballs, so the eyes are more similar in structure to the telescopes. The eyes cannot move, but evolution compensated for this shortcoming with the mobility of the head, which can turn almost a full turn around the neck (to be precise, 280 degrees – 140 in each direction). In addition, they have very sharp eyesight.
Owls have not two, but three pairs of eyelids, each of which performs its own function. One is for blinking, one is for eye protection while sleeping, the other is used as car wipers to keep it clean.
Appearance and Features
The polar owl is very large compared to other birds of the tundra. Its average wingspan is one and a half meters. The maximum known size was 175 cm. Interestingly, this is one of the few species in which females are larger than males. In particular, their body length is from sixty to seventy centimeters, while the maximum size of the male is only 65 centimeters. Body weight in females is also greater – about three kilograms. Males weigh only two and a half kilograms on average.
The plumage of the snowy owl is very dense and quite warm. Even the legs are covered with thin feathers that look like wool. Small feathers also hide the bird's beak. This is due to living in conditions of fairly severe cold. In addition, the feathers of an owl have a special structure with a swirl, thanks to which it is able to fly almost silently. Another feature is that the snowy owl sheds with the change of seasons. She begins to shed her old plumage at the beginning of summer and for the second time a year – at the end of autumn.
The color, as you can already understand from the second name of the bird, is white. It is fully consistent with the habitat of the snowy owl. Due to the fact that it merges with the snowy background, the owl remains invisible to predators and to its prey. Scientifically, such a coloring corresponding to the background is called patronizing. There are dark spots on the plumage. Their arrangement is unique to each bird, like fingerprints are to humans.
The head of the bird is wide and rounded, it has small and almost imperceptible ears. But with their small size, the owl has excellent hearing and is able to hear rodents even at great distances. It is believed that the hearing of an owl is four times better than that of a domestic cat. The eyes are round and bright yellow. There are no eyeballs, like other owls. On the eyes, you can replace fluffy eyelashes. The beak is black, but inconspicuous, as it is hidden by feathers. Owls have no teeth.
An interesting fact: the snowy owl's head is very mobile and can easily rotate at least 270 degrees. This helps the owl a lot when hunting.
Where does the snowy owl live?
This bird is a typical inhabitant of northern latitudes, moreover, in both hemispheres. Its habitat extends in the tundra in the territories of Russia and Canada.
Individuals are found on the islands of the Arctic Ocean, including:
- on Novaya Zemlya;
- on Svalbard;
- on Wrangel Island;
- in Greenland.
In fact, snowy owls populate the entire Arctic. Previously, birds were also found in Scandinavia, which was reflected in the Latin spelling of the name of the bird Nyctea scandiac. But now they are very rare guests there.
The bird is partly nomadic. That is, she has wintering places and nesting places. But some individuals prefer to stay in their nesting places for the winter. At the same time, they choose areas that are not heavily covered with ice or snow. Migrations of snowy owls occur in the middle of the calendar autumn, then they return back at the end of March or at the beginning of April. Sometimes, but very rarely, birds fly into regions considered southern. For example, snowy owls were found in the Khabarovsk Territory, in Northern Japan and on the Korean Peninsula.
The owl prefers to settle mainly in open spaces, sometimes among small mountain hills, since it does not fly above 1000 meters above sea level. On the contrary, the snowy owl tries to avoid wooded areas, sticking more to the tundra and forest-tundra. This is due to the inconvenience of hunting in places with high vegetation. In times of famine, it happens that birds fly into villages in search of food, but this happens very rarely.
What does a snowy owl eat?
The polar owl is a typical predator. She eats only animal food and never eats any plants. She usually eats at least four rodents a day. With a smaller amount, an adult cannot be satiated. During the year, an adult owl eats about 1600 mouse-like rodents, mostly lemmings. Owls swallow small living creatures whole on the spot, and before eating large prey, they take it to themselves, and then tear it apart and eat the pieces separately. The owl burps its hair and bones.
In addition to rodents, the snowy owl is fed by:
- ermines and other small carnivores;
- baby foxes;
- ducks and small geese;
Ceteris paribus, the snowy owl prefers to eat small rodents in summer. She usually hunts large (relative to her own size) animals in winter. Many snowy owls have also been seen eating fish. In addition, in winter they do not disdain carrion.
Interesting fact: A snowy owl hunts from the ground. She sits on an elevated place and watches. Seeing the prey, she sharply flaps her wings, then flies up to the rodent and clings to it with her claws. But sometimes the snowy owl also uses another way of hunting – at low level flight.
If the prey is initially larger than the owl itself or their sizes are comparable, then, flying up, it bites into the prey and hangs not the victim until she stops resisting. The bird then beats the prey with its beak. This is how rabbit hunting happens.
Hunting usually begins at dusk, but the snowy owl cannot be called a strictly nocturnal bird. Departures for hunting can also happen in the early morning after a long break. Unlike other owls, the snowy owl is not entirely afraid of sunlight.
Personalities and lifestyle features
Snowy owls usually live far from humans, so not everyone can see it. A bird, like any strong predator, has its own temper. She is very strong and resilient. Almost all snowy owls lead a solitary lifestyle. They create pairs only for the breeding season, and only at this time they act together.
To communicate with each other and to scare off enemies, owls can make sounds. Sounds are similar to croaking, hooting and sometimes squealing trills. Owls communicate with each other only during the breeding season, so they are usually silent.
An owl spends most of its life either sleeping or stalking prey. An interesting feature of the polar owl is that it is able to lead a daytime lifestyle. Other owls hunt only at night.
The main object of hunting for owls are lemmings and other mouse-like rodents. By exterminating rodents, polar owls strongly regulate their numbers. The benefit of this is that in this way they are directly involved in the development of the tundra ecosystem. Another important ecological value of owls is that they are a factor in the successful nesting of other trundra birds.
Interesting fact: Snowy owls never hunt near nests, while they fiercely defend the area around them within a radius of about a kilometer. Some birds, such as gulls, are aware of this trait and deliberately nest near owls so that they can guard their nests as well.
Photo: Snowy Owl Chicks
Since polar owls are loners, they do not have any social structure of their own. During the nesting season, they create monogamous, but often disposable pairs. The mating season for snowy owls falls in the middle of the calendar spring.
As a sign of courtship for the female, the male brings her food, flies around her, flapping his wings strongly, and walks beside her, fluffed up. Usually a gift is a carcass of a lemming. To attract a female, he can also arrange demonstration races, running across the mounds, sometimes singing various sounds while doing this.
If the female gives consent, then the couple begins to take care of future offspring, for which they build a nest. The nest is very simple. It settles on bare ground, for which the bird digs a hole or a small depression with its claws. Additionally, the nest can be lined with dry grass, rodent skins or old feathers and down. Owls usually nest on dry slopes. On the islands, nests are built on ledges of coastal cliffs.
Owl eggs are laid not at the same time, but in turn. One egg per day. Although this interval can be much larger, reaching a whole week. Therefore, in the same nest, chicks are always of different ages. The females incubate the eggs for a month. The chicks hatch in the order they lay their eggs. During the incubation period, the male takes on the responsibility of obtaining food. But later, when there are a lot of chicks, the female joins the hunt. Usually the female stays in the nest and protects the chicks and eggs from predators.
An interesting fact: In well-fed years, the number of chicks in each nest can reach 15. In bad years, eggs are laid about half as many, but there are also cases when the brood does not appear at all.
Owlets are usually quickly mastered. Their eyes open on the tenth day. Usually at the same time they are overgrown with gray-brown fluff, which will then be replaced during the first molt. They themselves begin to crawl out of the nest, and after a month and a half they try to take off. They reach puberty in a year. The total life expectancy of a snowy owl usually reaches from ten to fifteen years. In captivity, owls live up to thirty years.
Natural enemies of snowy owls
Since the snowy owl looks like a very large bird compared to the rest of the inhabitants of the tundra, it is very rarely attacked. But, nevertheless, the snowy owl also has enemies, since its chicks remain under threat to predators. The hatchlings are often hunted by arctic foxes and foxes, and sometimes by skuas. Arctic foxes also like to climb into nests to eat owl eggs. Due to the fact that clutches of owls and their broods suffer greatly from arctic foxes, arctic foxes are considered the main enemy of the snowy owl.
Sometimes the death of chicks is due to the aggressive behavior of the older ones. Large chicks are able to destroy the younger brother, and then even eat. But cannibalism is usually a very rare occurrence for them. Very often, younger owlets die of starvation due to the fact that older chicks take away food brought by their parents.
Predators almost do not hunt adult owls, but if this happens, the owl spreads its wings wide and frightens the enemy, demonstrating false attacks. More often, snowy owls simply fly away from predators, having heard or seen the enemy on the way. If it happens that an adult owl is taken by surprise by a fox or other predator, then it simply rolls over onto its back and fights off the enemy with its clawed paws.
If the enemy attacks the owl's nest, then it tries to block its path in order to protect the chicks. She flaps her wings in front of the muzzle of a predator, periodically flies up and then falls on him, grabbing with her claws. Usually these measures are sufficient.
Population and species status
Today, polar owls are a rare species. In North America, the total population has declined by 53% since the mid-1960s. There are reasons to believe that in Russia and northern parts of Europe the picture may be similar. What is known for certain is that in their usual habitats, the number of birds has noticeably decreased, and they have become less common.
The species has the status of vulnerable, but so far they are not threatened with extinction, and no additional measures to protect the polar owls are not undertaken. The average nesting density of these birds is about fifty pairs per hundred square kilometers. The world livestock has about 28,000 individuals, which is quite a lot. But some scientists consider these data to be highly overestimated, and suggest that snowy owls will soon receive the status of the Red Book.
What exactly caused the decline in the number of snowy owls is not known for certain. Climate change may play some role in this, as it affects the size of the food supply. Some damage to the population is caused by human activity. It happens that a polar owl dies in traps. Traps in many areas are specially placed by commercial hunters. In North America, owls also die when they collide with cars or high-voltage lines.