Engoulevent diabolique

Identification

The Satanic nightjar measures about 27 cm (11 in) long. It has a white to buff-colored collar at its throat, blackish head, greyish-brown back, barred brown belly, and white spots on its 3rd and 4th outer primaries. It can be distinguished from other nightjars in the area by its dark color and the absence of ear tufts, white tail, and wing patches.

Taxonomie

The Satanic nightjar belongs to the order Caprimulgiformes, and the nightjar family Caprimulgidae, falling within the genus Eurostopodus along with six other birds. Though it is sometimes confused with other nightjars found within its range such as great eared nightjar (Eurostopodus macrotis), savanna nightjar (Caprimulgus affinis), and the Sulawesi nightjar (Caprimulgus celebensis) it is believed to share a closer evolutionary origin with New Guinea nightjars including Archbold's nightjar (Eurostopodus archboldi) and the Papuan nightjar (Eurostopodus papuensis), which it most resembles in appearance and habitat preference. Though Satanic nightjars have always been treated as a single species, recent comparisons of photographed and observed individuals have revealed differences which could indicate there are in fact two separate types. Individuals from central Sulawesi have grey on their tails and scapulars, along with white-tipped, oval-shaped breast feathers. Conversely, individuals from the north of the island lack grey markings and have less pronounced breast feathers. Regional differences in the birds' song may also exist. However, more evidence must be gathered before any conclusions can be drawn.

Nom scientifique

Eurostopodus diabolicus

Autorité

Stresemann, 1931

Ordre

Caprimulgiformes

Famille

Caprimulgidés

Genre

Eurostopodus

Répartition et habitat

The Satanic nightjar is restricted to Sulawesi, Indonesia. It inhabits lowland and mountain rainforests of the region from 250 to 2,300 metres (820 to 7,550 ft) above sea level. It seems to favour edge habitats with low canopies and groves of palms and rattans. It can be found in forest clearings, as well as open spaces created by roads and trails in old-growth forests. While it has mostly been sighted in the north and central parts of the island, its range could extend over all of Sulawesi.

Migration

Resident species

Comportement

The Satanic nightjar makes a range of different vocalizations. While flying, the bird produces a burst of loud, ascending, "fWIP! fWIP" notes set at 1 second intervals. These notes can also occur more sporadically, sometimes sung suddenly and close-together in pairs of "fWIP-WIK!, fWIP-WIK!" where the last note is shorter and sharper than the first. When at rest, the bird might trill a string of quick, constant notes "TWIk-TWIk- TWIk" which sound similar to its paired calls. Each note begins loudly but ends softly and the song generally decreases in volume and pitch, lasting about 2–6 seconds. In one recorded trill call, the song was preceded by a small number of weak, low qu/wick! sounds. When disturbed, the nightjar may also make growling noises, which accompany a threat display. Nonetheless, the bird vocalizes rarely, which may partly explain its elusiveness.<p>Like other nightjars, this bird preys on insects while flying. It hunts along the forest edge, active near dusk and dawn. However, little is known about its diet. It is thought to feed primarily on nocturnal insects such as moths.<p>The Satanic nightjar has a generation time of 5.4 years. It breeds from March to October, though this range might actually encompass two distinct breeding seasons. It roosts and nests on the ground, its cryptic plumage helping it blend in with the surrounding leaf litter during the day. The bird builds nests in open areas with a bit of cover from surrounding logs and vegetation such as ferns and moss. Its nest consists of a shallow scrape and a few leaves, with one nest measured to be 1 cm (0.39 in) deep and 14 cm (5.5 in) wide. In this, the bird will lay a cream-colored egg with brown spots. Observed nests have typically contained only a single egg or chick which the parents raise for a month or more. When its offspring are threatened, the Satanic nightjar has been observed to spread its wings and tail, and gape widely, sometimes calling or agitating its body.

Conservation

Tendance de la population

declining