Solar declination as an index of northern bird migration
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Every year, in autumn, birds from the northern temperate zone migrate south. Venezuela is a destination for these birds.
Autumn in the north begins around September 22. But birds don't manage dates. They manage the cycles of nature. We have wondered what is the natural signal to begin their migration.
In several years we have learned and followed the solar declination, the geographical location where the sunlight is falling perpendicularly.
We take this index in our careers to tell our patients and our readers, the canícula, the hottest time in our country. But in three years in a row, we have noticed that when the solar declination arrives in the state of Zulia, in Venezuela, when the sun's rays are located perpendicular in Venezuela.
It is the month of the celebration of World Beaches Day (third Saturday of September). On this ephemeris, migratory birds also begin to arrive.
This year, one day after World Beaches Day, from my home, located south of the city of Maracaibo, we were able to observe four ospreys in the skies over our city.
Ospreys come from North America, migratory birds, which along with others gave wetlands protection status in the Iranian city of Ramsar, the eponymous international treaty for the protection of wetlands.
This bird, the osprey, belongs to the Animal Kingdom, Phylum Cordata, Class Bird, Order Accipitriforme, Family Pandionidae, Genus Pandion, Species Pandion haliaetus, according to scientific classification.
Three years in a row the ospreys arrive to our Venezuelan state of Zulia, to our city of Maracaibo when the solar declination is located in our country. We can say that when the solar declination is located in Venezuela, when the sunlight is perpendicular to Venezuela, migratory birds from North America begin to arrive to our Bolivarian Republic of Venezuela. Also as a reference, we can have the World Beaches Day Celebration.
Hello @eliorrios, Autumn is my favorite season of the year, the migration of birds is very noticeable in my city, I am in the east of the country although sometimes it could be very easy for us to confuse them with local birds.
I guess you don't live in Venezuela because there is no autumn here, although there are times when what you are talking about happens.
Hello @eliorrios, I'm in Venezuela just right now, and here we have autumn but it goes unnoticed, I realize the entry of autumn just because of the solar declination because at this time "in the east" the sun has a slightly different aspect and we know that then December is very close hahaha