The dust removes visibility so they follow the animals in front of them.
On safari in Masai Mara Mara Conservancy at Kitchwa Tembo Camp at 10:08 on 06-Sep-2013.
————–Shooting data——————–
Date: 10:08 on 06-Sep-2013.
Model: NIKON CORPORATION NIKON D800
Lens: VR 600mm f/4G IF-ED 600
Settings: 640; 11; 1/2500; 18.2