The Deer’s Eyes Are Also Covered With A Cloth After The Drops Are Applied. The Cloth Over The Eyes Serves To Minimize Stress By Preventing The Deer From Seeing What Is Going On Around It. Researchers Never Know Exactly How Much Of The Drug Is Delivered To An Animal Through A Dart, Or How Sedated It Is When They Approach. Just Because An Animal Cannot Move Does Not Mean It’s Asleep Or Unaware Of It’s Surroundings. For Those Reasons, This Is Why Researchers Also Remain As Quiet As Possible.