Black sun: There are birds that make this oxymoron a reality!

We all have seen the changing hues of sun at different times of the day. But have you ever seen this ball of fire turning black? No, we are not referring to any fictional setting from a painting or a movie. It actually happens in Denmark when swarms of flying starlings block the sun. The Danish call this mesmerising phenomenon Sort Sol, which means Black Sun in English. The breath-taking that those black birds create in the sky is a feast to the eyes for sure!  

Sort Sol decoded  
The magnificent sky show pans out when our dear starlings, millions in numbers, flock together and fly in patterns during a migratory phase in spring (March to April) or autumn (September to October). The spectacular phenomenon, which lasts for about 20 minutes, occurs during dusk on the coastal wetlands of south-west Denmark where these speckled black birds stop over. What do the birds actually do to paint the sun dark? They flock together from all corners of the sky just before the sun sinks below the horizon, and indulge in a variety of moves like swooping, diving and whirling. In this unique and stupendously beautiful twilight ritual, which resembles an aerial ballet, the starlings eclipse the fading sun by forming a large black cloud while creating a variety of shapes such as spheres and arches. After this splendid 20-minute show is over, come down to the marshy land to rest through the night. Surprisingly, the movements of this flocking behaviour aren’t planned as there is no leader they follow. Scientists speculate that the birds observe and follow what the others in the flock are doing and adjust accordingly. 

An act of self defence 
Are you wondering why starlings engage in this flocking behaviour at all? Well, it’s not a playful act as you might have assumed. This acrobatic show that they put up in front of the sun is actually a defence mechanism to track and keep the predators at bay. It becomes tough for the predators to catch a prey from a crowd of thousands. Now, that’s interesting, isn’t? 

Vadehavet: A Sort Sol venue that has become a UNESCO 
Vadehavet, or the Wadden Sea, is another place in Denmark where you can experience Sort Sol. In 2014, it was designated a UNESCO World Heritage Site. It is situated among the Jutland peninsula's wetlands and is the world’s largest tidal area. This area is rich in fauna, including insects and smaller prey. It is said that the Wadden Sea is the best place on earth to view starlings flying in formation during their migration.