This shot was taken from an observation deck over the waterfalls and the amount of mist/moisture here was incredible. The wind was pretty strong as well, making picture taking difficult without getting water droplets on you lens. There are swifts that nest behind the waterfalls and they flew around in flocks. Based on their tiny size, however, they are barely noticeable on the image. Those tiny dark spots, mostly in the lower right hand corner, are actually swifts and not dust on the camera sensor.