Uploader Oipoistar was in Rijeka, Croatia when he captured this gripping slow motion footage of a flock of birds suddenly taking flight from a tree. In the video, you can hear birds chirping but you can’t see them in the tree. That is until, all of a sudden, dozens of birds leave the tree after getting frightened. Oipoistar’s camera captures every moment and it’s only in slow motion that you get an idea of just how many birds there were. Credit: YouTube/Oipoistar