The distinct calls of owls echoing through the night spark wonder. These elusive birds, often more heard than seen, possess a unique presence in the nocturnal soundscape. Their vocalizations, ranging from deep hoots to sharp screeches, serve specific purposes, offering a glimpse into their hidden lives after dusk. Understanding why owls are active at night and what their diverse calls signify helps unravel the mystery surrounding these fascinating creatures.
Why Owls Are Active at Night
Owls are primarily nocturnal. This lifestyle is supported by specialized adaptations that allow them to thrive in low-light conditions. Their large, forward-facing eyes are packed with light-sensitive rod cells, enabling them to gather even the faintest available light, far surpassing human night vision. While their eyes are fixed, owls compensate by rotating their heads up to 270 degrees in either direction, providing a wide field of view without moving their body.
Beyond exceptional sight, owls possess highly acute hearing. Many species have asymmetrically placed ear openings, allowing them to pinpoint the exact location of sounds in three-dimensional space, even in complete darkness. A facial disk of feathers around their face acts like a satellite dish, channeling sound waves directly to their ears. Additionally, their feathers are structured with comb-like serrations and a velvety texture, enabling virtually silent flight. This combination provides a significant advantage for hunting nocturnal prey like rodents and small mammals, and minimizes competition with diurnal predators like hawks and eagles.
Understanding Owl Calls
Owls vocalize for a variety of reasons, communicating information within their species. A primary purpose of their calls is to establish and defend their territory. Loud hoots are frequently used to mark their presence and signal to rivals that an area is occupied.
Vocalizations also play a significant role in attracting mates and maintaining pair bonds. Males often use specific calls to court females, and mated pairs may engage in duets, with slight pitch differences. Owls also use calls to communicate with their offspring, such as begging calls from chicks. Shorter, sharper calls function as warning signals, alerting other owls to potential threats or indicating distress.
Owls You Might Hear at Night
The Great Horned Owl, a widespread and adaptable species, is known for its deep, resonant hoots, often described as a series of five “hoo-hoo-hooooo-hoo-hoo” notes. These powerful birds inhabit nearly all habitats, from forests and wetlands to urban areas, across North and South America. Their calls are heard year-round, particularly during the winter breeding season.
Another commonly heard species is the Barred Owl, recognizable by its characteristic “Who cooks for you? Who cooks for you all?” hooting sequence. These owls prefer dense, moist forests and wooded swamps, often near water, and are abundant in North America east of the Mississippi River, though their range has expanded westward. Mated Barred Owl pairs sometimes engage in a noisy duet of cackles and gurgles.
The Eastern Screech-Owl, a smaller owl, produces a distinctive descending whinny call, similar to a miniature horse, and a soft, monotone trill. Despite its name, this owl does not truly screech. They are common in open woodlands, parks, and suburban areas across eastern North America, often nesting in tree cavities or abandoned woodpecker holes. Their calls are often heard during their spring breeding season.
Barn Owls are strictly nocturnal and widely distributed across every continent except Antarctica. Unlike many other owls, they do not hoot. Instead, their signature call is a raspy, drawn-out scream or shriek, often used for communication and as a warning. They typically hunt over open land like marshes, grasslands, or farms and often roost and nest in quiet cavities, including barns and silos.