Grey-lined Hawk

Quick Facts

• Scientific Name: Buteo nitidus
• Spanish Name: Gavilán gris
• Family: Accipitridae
• Known Nicknames: Gray-lined Hawk, Shining Buzzard-Hawk
• Average Length: 38–46 cm / 15–18 in
• Average Weight: 400–612 g / 14.1–21.6 oz
• Wingspan: 75–94 cm / 30–37 in
• Key Feature: Fine grey and white horizontal barring on underparts and solid grey upperparts
• Primary Diet: Carnivore (primarily lizards, snakes, and small mammals)
• Range: South America, from Costa Rica and Panama to northern Argentina and Paraguay
• Habitat: Lowland tropical forests, forest edges, and riverine woodlands
• Social Structure: Solitary or monogamous pairs
• Nesting/Breeding: Stick nests in the canopy of tall trees
• Conservation Status: Least Concern (LC)
• Population Trend: Stable

The Grey-lined Hawk (*Buteo nitidus*) is an elegant Neotropical raptor distinguished by its sophisticated silvery-grey plumage and the fine, rhythmic horizontal barring across its underparts that gives the species its name. Unlike many of its bulkier cousins, this hawk possesses a surprisingly slender, Accipiter-like silhouette with relatively short, rounded wings and a long, black tail punctuated by bold white bands—adaptations that allow it to maneuver with lethal agility through forest edges and riparian woodlands. Its striking appearance is completed by a piercing gaze from bright yellow eyes and a matching yellow cere, which stand out against its pale, ashy face. A master of the "perch and pounce" hunting technique, this vocal predator is often announced by a high-pitched, whistling scream that echoes through the tropical savannas and scrublands it patrols in search of lizards and small reptiles.

Fun Facts

The Grey-lined Hawk is a specialist predator with a diet consisting almost entirely of lizards and snakes, often perching motionless for long periods before executing a lightning-fast strike. One of its most unique behaviors is "commensal foraging," where it follows swarms of army ants to snatch up small vertebrates fleeing the insects. To navigate its dense forest habitat, this hawk has evolved shorter, more rounded wings than many of its soaring relatives, allowing for extreme maneuverability through thick canopies. Despite its fierce hunting reputation, its vocalization is surprisingly delicate, consisting of high-pitched, musical whistles that sound more like a songbird than a raptor.

Habitats & Distribution

The distribution of this species spans primarily across South America, ranging from Colombia and Venezuela southward through the Amazon Basin to northern Argentina and southern Brazil. While closely related populations in Central America and the southwestern United States are often classified separately, this raptor is a characteristic inhabitant of the Neotropics, favoring lowland regions east of the Andes. It thrives in semi-open environments and transitional zones, such as forest edges, gallery forests along riverbanks, and savannas interspersed with trees. It generally avoids the interior of dense, unbroken rainforests, preferring habitats that provide a mix of tall perches for hunting and thick foliage for nesting. Deciduous woodlands and scrubby areas near water sources are also frequently occupied.

Behaviours & Reproduction

These raptors are primarily solitary or found in monogamous pairs, maintaining well-defined territories through vocal displays and high-perch hunting. During the breeding season, their behavior becomes more conspicuous as they engage in aerial displays and emit piercing, high-pitched whistles to defend their nesting sites. They typically construct small stick nests lined with fresh green leaves, situated high in the canopy of tall trees, frequently near riverine corridors or forest edges. Reproduction involves a clutch of one to three eggs, which the female incubates for approximately 30 days while the male provides her with prey. A notable reproductive strategy is the continuous addition of green nesting material throughout the brooding period, which is thought to help repel parasites or regulate humidity. Once the chicks hatch, they are brooded by the female and fed by both parents, eventually fledging at about six weeks of age while remaining socially dependent on the adults for several additional weeks.

Diet

The Grey-lined Hawk is a specialized carnivore whose diet is predominantly composed of reptiles, with lizards such as whiptails and iguanids often making up the vast majority of its prey. While it is primarily a lizard-eater, this raptor is also an opportunistic hunter that consumes small mammals, snakes, frogs, and large insects like grasshoppers and beetles. Interestingly, unlike many of its relatives in the Buteo genus that favor rodents, the Grey-lined Hawk's hunting strategy is finely tuned to the movements of arboreal and terrestrial reptiles, often utilizing a sit-and-wait approach from a high perch before performing a swift, agile strike. Its ability to navigate through dense canopy edges allows it to capture fast-moving prey that other hawks might overlook, making it a key predator of reptilian populations within its tropical and subtropical forest habitats.

Colors

The Grey-lined Hawk is characterized by pale lead-grey upperparts and distinctive, fine horizontal grey-and-white barring across its chest and belly. Its black tail features a prominent white median band and a narrow white tip, while its cere and legs are a contrasting bright yellow. This delicate, monochromatic patterning serves as effective camouflage, allowing the hawk to blend into the dappled light and shadows of the tropical forest canopy.