Long-winged Harrier

The Long-winged Harrier, Circus buffoni, is a mid-sized raptor endemic to South America. Exhibiting sexual dimorphism, females are larger than males, with males weighing between 390 to 464 grams and females ranging from 400 to 645 grams. Their body length spans 46 to 60 centimeters, and they boast an impressive wingspan of 120 to 155 centimeters. Characterized by long, narrow tails and particularly elongated wings, their plumage is predominantly grey with darker primary feathers and streaks of white, grey, and brown.

Identification Tips

Males of this species come in two morphs: light and dark. The dark morph features an entirely black belly with females showing a brownish tinge, while the light morph is distinguished by stark white underparts. Juveniles resemble females but have a more speckled chest. The species can be recognized by its bright orange legs, sharp talons, and large hooked beak typical of raptors. A unique feature among diurnal birds of prey is their facial disc, a circle of feathers enhancing their auditory capabilities for hunting.

Habitat

The Long-winged Harrier frequents expansive grasslands and agricultural fields, as well as savannas, marshes, and wetlands across South America. These environments support their active hunting techniques.

Distribution

This harrier's territory covers much of eastern South America, including eastern Argentina, Uruguay, Brazil, Paraguay, Colombia, Venezuela, and the northern regions of Guyana, Suriname, and French Guiana. Sightings have also occurred in Bolivia, Peru, Chile, Trinidad and Tobago, and as far south as Tierra del Fuego in Argentina. It is occasionally seen in Panama and the Falkland Islands.

Behaviour

The Long-winged Harrier employs an active hunting strategy, flying in large circles at low altitudes to locate prey using its keen vision and hearing. This method contrasts with the more passive approach of other sympatric raptors.

Song & Calls

This species is not particularly vocal, but when it does call, it is often in flight. Its vocalizations include a rapid "klee-klee-klee" and a softer "thrill" with a descending pitch.

Breeding

Nesting occurs on the ground between September and October, with nests constructed from rushes and grass close to water sources. The breeding season varies across their range, typically during the summer months, with clutches averaging 3 to 4 eggs.

Conservation Status

The Long-winged Harrier is classified as 'Least Concern' by the IUCN Red List, despite a noted population decline due to habitat degradation, particularly in wetlands. While no specific conservation measures target this species, it benefits from the protection of various conservation sites within its range.