Swallows are characterized by their migratory habit, but why do they migrate? This post will explain the reasons that lead them to travel all over the world, as well as some important characteristics that will help you get to know them better.
Golondrinas
Before talking about why swallows migrate, it is necessary to know a little about them, they are called andorinas or swallows but their scientific name is hirundo rustica, belonging to the Hirundinidae family. It is well known both for its striking colors and for its habit of migrating in large groups until it fills the sky with gray dots (which are each one of them), these birds have been seen in the European continent, Asia, the African continent and in North and South America.
It is not part of the group of endangered animals worldwide because there are many specimens distributed across the continents mentioned above. Furthermore, its migrations are easily recognized by the large number of swallows seen in the places they arrive, and its reproduction rate is not very limited. However, the fact that there are many specimens does not exempt them from the risk of threats such as hunting.
What do swallows look like?
These birds are small and measure between 14 and 34 centimeters, their feathers can be quite long, reaching 7 centimeters, and they also weigh from 16 to 22 grams. As for their colors, these are blue, red and brown in youth, blue is seen in the upper part of their body with great intensity and metallic tones, they can show a slightly dull red in the throat, on the forehead and on the chest. the chin but there are some that have a deep red chest.
They can also have white lines on the upper part of their tail but not in all specimens, the brown is a sign that they are young and their faces are also a little red but with a certain paleness, on the lower part they can be white and it is only when they reach maturity they show the metallic blue color that characterizes them.
These birds are a little difficult to differentiate by their color if you want to know which is the female and which is the male, but their size is a good indication since the females have a slightly shorter tail than the males, in addition to their colors. they are duller than those of the male. The legs of both sexes are gray and allow them to perch horizontally, making it easy for them to fly off the ground.
Their life expectancy is sixteen years in most cases. As for the subspecies found, six can be identified:
- The Hirundo rustica: which would be the nominal species found in Europe, Aria, Iraq, China, India, Africa, Russia, Arabia and other countries, traveling on migration to southern Africa. Some Barn Swallows have a pectoral band that is slightly red and some may have white on their undersides. These can be found in shades of pinkish, cream, white, and violet-blue.
- Hirundo rustica transitive: Found in the Middle East, migration to Turkey and Israel can be seen but they generally winter in East Africa. Its physical description shows red at the bottom and even orange unlike the nominal species.
- Hirundo rustica Gutturalis: They usually reproduce in Japan, Korea, the Himalayas, Alaska, Washington and the Philippines, they are characterized by having a rusty ocher color in their lower part and the blue of the upper part not in a violet tone but greenish, in addition to that some specimens can have a red color in its lower part.
- Hirundo rustica tytleri: Its breeding areas are Mongolia, Siberia, Malasi and even in China, its tail is a little longer than that of the other subspecies and its lower part has brown tones.
- Hirundo rustica erythrogaster: This is considered an American subspecies because it breeds throughout North America, in Mexico, Alaska, throughout South America, Costa Rica, the Lesser Antilles, and Panama. What differentiates this species from the previous ones is that it is much redder and more intense, however it can be very similar to the transitive Hirundo rustica.
Regarding their behavior, these birds are diurnal and have migratory habits that distribute them all over the world in large groups. As they stay in groups, they sing in a choir, although they also sing alone. They are aerial insectivores, so they feed on the insects they catch when they are flying, some prey are captured when they fly on the surface of the sea but they also eat grasshoppers, flies, beetles, crickets, mosquitoes, dragonflies and moths that are on walls.
migration of swallows
Swallows are one of the many animals that migrate, but their habitat is the open countryside. This can include meadows, land where agricultural products are grown, and places where there is not too much vegetation or too many people. They prefer places where there are bodies of water nearby and they like stables, barns, and other open man-made structures.
They are beautiful and quiet places, so people often wonder why do swallows migrate? Even when they are migrating, they do it over open areas and avoid mountains, even so they do not like deserts or cold places, they also avoid cities although they usually make nests in people's buildings, in tree holes, in human houses, in ravines, sheds, barns, among other structures.
The reason why swallows migrate in the first place is for survival, they travel when the weather changes and they need a new shelter where they can breed and build their nests. They also migrate to find more food in other parts of the world and thus feed their young well.
The specimens that migrate most frequently are those found in areas with a temperate climate, to escape the cold of winter, an example of this are the swallows found in Uruguay, which travel to that country when it is summer but They breed in North America. There is a group of them that reproduce and stay in Uruguay for a while but travel to the north of that continent when winter approaches.
Other swallows usually breed in southern South America but migrate to Uruguay, Paraguay and Argentina, although they also go to Brazil (to the south). Continuing with the swallows in America, there are some that travel to Europe in March or April and then go to southern Africa, their arrival announcing that summer or spring is beginning in some of the countries to which they migrate.
Those found in Europe actually travel to many places, some go to Africa after breeding, others go to Morocco, South Africa, and others may return to North or South America. The truth is that they can be seen easily because they do not fly very high and they do it during the day preferably to be able to rest at night in open places that are called roosts.
Spain was a starting point so they were not often seen there but it has been observed that lately they spend much more time in the south of this country, almost all year round. It would be as if their migration dates change or are delayed by themselves, this may be because they expect better times to get food to their destination and a better time.
This may be because climate change has significantly affected some locations and some birds may stop being migratory and become residents of the countries in which they are found. The downside of this is what was explained about why swallows migrate, that it is survival that moves them to move to places with better climates. If climate change continues, it is possible that many of them will die due to unbearable temperatures.
Where exactly do they migrate to?
Previously many of their migration places were mentioned, specifically each subspecies tends to migrate to a certain country, the interesting thing about their migration is that they are moving forward more and more and that is an indicator that there are important changes in the world's climate , the meteorological conditions are altered, as well as the temperature and that is key to analyze the environmental change that the world suffers due to pollution and human activity.
