The iris is bright yellow and the bill is grey-green, with tufts of bristly feathers around its base. They can also be distinguished by their different calls, and only occur together locally in eastern Colorado and southern Texas. They rarely glide or hover, but may fly with erratic movements, when manoeuvring through wooded areas. Their wings are broad and the head is held tucked in giving the bird a stubby appearance when flying. When threatened, an Eastern Screech Owl will stretch its body and tighten its feathers in order to look like a branch stub to avoid detection, but will take flight when it knows it has been detected.
Males have a lower-pitched voice than females.
The male's most common call is an eerie, mellow, muted trill given during the mating and nesting seasons. Each call lasts 2 to 3 seconds with about 35 notes given, and repeated at various intervals. This call is primarily territorial in nature and announces ownership of nest cavities. When in the nest with young, adults give a descending whinny call , instead of the normal call. This whinny call is given through the winter until the mating call begins again.