Grey-lined Hawk (Buteo nitidus)
About the Grey-lined Hawk
The gray-lined hawk (Buteo nitidus) is a smallish raptor found in open country and forest edges. It is sometimes placed in the genus Asturina as Asturina nitida. The species has been split by the American Ornithological Society from the gray hawk. The gray-lined hawk is found from El Salvador to Argentina, as well as on the Caribbean island of Trinidad. The gray-lined hawk is 46–61 cm (18–24 in) in length and weighs 475 g (16.8 oz) average. The adult has a pale gray body, the tail is black with three white bands and the legs are orange. It has fine white barring on the upper parts.
Ecology and behavior
As a member of the Accipitridae, this species is associated with open country, woodland edges, wetlands and mountain terrain. It typically feeds by soaring, perching and scanning for vertebrate prey or carrion. That combination of habitat and feeding behavior explains where the bird is easiest to find and why it may be heard more often than seen. Across its range, recorded examples are linked to Ecuador, Venezuela. Local habitat can change the exact impression of the voice, but the useful field method stays the same: note the perch, surrounding vegetation, and whether the bird repeats one phrase or gives separate contact sounds.What to listen for
High, clear calls are often short and piercing; listen for spacing and whether notes are level or falling. The recordings on this page are labeled here as call. Compare each phrase in three passes. First follow the rhythm and repetition. Then judge whether the tone is clear, burry, buzzy, rounded or harsh. Finally notice the pitch direction and the spacing between statements. These three features are more reliable than trying to translate the sound into words alone. A useful field note should describe the whole phrase before naming the bird. For this species, write whether the sound stays level, rises or falls, how long each series lasts, and whether the bird seems exposed, hidden in cover, or associated with a particular edge between habitats. Those details make the recording transferable to a real outdoor encounter.A field note on this voice
When you are most likely to hear this voice
The recordings featured here were made in February, October. Those months may offer a useful seasonal clue, but vocal activity can vary widely across regions and years. Weather, latitude, food availability and local breeding cycles may all influence when a bird chooses to sing. Think of the timing as a starting point rather than a rule. The examples on this page come from recordings made in Venezuela, Ecuador. In the field, behavior and habitat often provide stronger evidence than the calendar alone.
Time of day
These particular recordings were made later in the day, usually around 13:00. Many birds are especially vocal in the early hours, when sound may carry well and singing can be a regular part of the morning. Birds may also vocalize later in the day while feeding, moving between perches, interacting with nearby individuals or responding to changes around them. Listening conditions can change how a sound is perceived. Returning to the same recording at different times and imagining the surrounding cover, light and weather can make the context easier to hear.
What this vocalization may suggest
This page contains call. Songs are often longer, more structured and more repetitive than short calls. A clear phrase repeated at regular intervals can be associated with breeding activity or the defense of space, although the exact context is best confirmed by observation. Shorter notes may accompany movement, alertness or contact with nearby birds. Faster, louder or harsher delivery can sometimes reflect heightened interaction, while an evenly spaced performance may simply be routine. Notice the surrounding behavior before deciding what the sound might mean.
Understanding pitch
High notes do not automatically indicate courtship, and low notes do not necessarily signal alarm. Pitch works alongside rhythm, repetition, volume and tone. A high, clear phrase may be a territorial song, while high, irregular notes might suggest agitation; some low, soft sounds may simply help birds stay in contact. Rather than focusing on pitch alone, observe what the bird is doing before and after the sound. The most useful field note combines the voice with place, time and behavior.
Editor's note
These interpretations are intended as listening guidance based on the available recordings and context, not as proof of an individual bird's intent. Strong observations note the date and time, habitat, perch height, weather and behavior before and after the vocalization.
A real field recording of the Grey-lined Hawk. Press play and focus on the rhythm and pitch of each phrase.