It is not only the mammals that are congregating around the waterholes of Savute, even the birds are flocking to get some water. Guinea fowl, Doves, Vultures and a myriad of other species are ascending in ever increasing flocks on the edges of the water. One of the most abundant species in this regard is the Redbilled Quelea. Flocks, often numbering millions are descending on the waterholes in front of the camp. As one of our guests recently exclaimed: “It sounds like a distant explosion as the millions of wings beat the air when taking off” The sound often carries for hundreds of meters as the flocks swirl in the sky.
From a distance the flocks look like smoke in the sky. Ever changing patterns as the birds turn and twist in the air. They appear very similar to sardines schooling in the ocean, large groups moving in perfect harmony. This synchronized movement is enabled by a phenomenon of sight known as the flicker effect. Human sight sees images flickering at a rate of around 25 images per second as fluid motion, a relatively slow rate of sight. The Queleas are much more advanced in this regard, seeing more than 300 frames per second. The smallest movement of the bird next door can therefore be acted upon a lot faster, something crucial if you want to avoid a midair collision. Imagine trying to run on the ground in crowds of more than a million people, all a couple of centimeters apart. Now try and imagine doing this without even touching the person next to you – impossible! Yet the Quelea is not doing this in the two dimensions on the ground, but in the three dimensions of space. They do not only recognize the movements of the birds in front and to their sides, but also the birds above and below them, acting accordingly in order to avoid any collisions.
Quelea are currently starting to enter breeding season in the region, and are starting to congregate around the breeding sites in the area. This herald a time of plenty for a lot of other species. Raptors can often be seen flying around the nesting site and often some are seen on the ground, too heavy with food after raiding the nests of the Quelea. Snakes are also common around the breeding colonies. Making their way from one nest to another and swallowing eggs, chicks and adults as they go. Even the smaller carnivores are making the most of the meal. Slender mongoose, African Wildcat and Blackbacked Jackal can often be seen foraging around the nesting sights, looking for any stragglers or dead chicks that were kicked out of their nests.
The advantage of living in such large flocks is that here safety lies in numbers. With millions of eyes scanning the skies for predators the presence of danger is noticed very quickly. One bird on his own makes an easy recognizable target for Raptors, but to pick one target out of a group of millions is a daunting task.
The advantage of living in such large flocks is that here safety lies in numbers. With millions of eyes scanning the skies for predators the presence of danger is noticed very quickly. One bird on his own makes an easy recognizable target for Raptors, but to pick one target out of a group of millions is a daunting task.
Yellow billed Kites are often seen trying to target the flocks around the waterholes, very seldom with any success. A few unlucky ones are picked up out of the water where they were pushed into by the flock, but the majority of the birds escape unharmed.
Look at the smaller things in nature, such as the Quelea, to add some spice to your next trip to the bush.
Kobus Lubbe – Savute Safari Lodge Manager
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