wild horses catching a breeze

animals arid badlands black breeze breezy brown brush catch catching crest dakota dakotas desert drought dry farm foal gray grey heat herd hill hilltop horizontal horse horses hot jostle layers mane manes mare mingle nature rock scrub stud summer white wild wildlife equus feris theodore roosevelt national park service juvenile social pets tamed docile territory mustang mustangs pet overpopulation overpopulated birth control starvation mitigation mitigate volunteer volunteers kill humane inhumane