Sickle-winged Nightjar vs Spotted Nightjar
Eleothreptus anomalus compared with Eurostopodus argus
Side-by-Side Comparison
| Attribute | Sickle-winged Nightjar | Spotted Nightjar |
|---|---|---|
| Scientific Name | Eleothreptus anomalus | Eurostopodus argus |
| Order | Caprimulgiformes | Caprimulgiformes |
| Family | Caprimulgidae | Caprimulgidae |
| Conservation Status | Vulnerable | Least Concern |
| Length | — | — |
| Wingspan | 25.8 cm (10.2 in) | 42.7 cm (16.8 in) |
| Weight | 43.7 g (1.54 oz) | 102.5 g (3.62 oz) |
| Diet | Aerial insectivore; hawks moths and beetles at night over South American wet grassland and marshes. | Aerial insectivore; hawks large moths, beetles, and flying insects at dusk and dawn over Australian … |
| Clutch Size | 2 | 1 |
| Population Trend | — | — |
Habitat Comparison
Shared Habitats
Sickle-winged Nightjar only
Spotted Nightjar only
Song & Call Comparison
Sickle-winged Nightjar
Soft churring call; low-pitched, repetitive trill from grassland; males produce distinctive wing noise in display flight; vocalizations quiet compared to wing sounds
Spotted Nightjar
Loud churring 'good-lord-deliver-us' repeated at dusk; melodic bubbling quality; also emits hollow 'cow-cow-cow' series and soft frog-like croaking
Geographic Range & Migration
Sickle-winged Nightjar
Resident of open marshland, wet grassland, and savanna from Paraguay and adjacent Bolivia south to Uruguay and northeastern Argentina.
Spotted Nightjar
Resident and partial migrant of open woodland, grassland, and scrub across mainland Australia and migrating to New Guinea and Indonesia in winter.
Conservation Status
Sickle-winged Nightjar
Spotted Nightjar
How to Tell Them Apart
Sickle-winged Nightjar
Male with extraordinarily elongated sickle-shaped outer primaries; dark brown with buff mottling; white throat and wing spots. Female brown with buff spots; normal wing shape; male wing shape unique among …
Spotted Nightjar
Cryptically mottled grey-brown, rufous, and black with intricate vermiculations; distinctive large white spots on wing coverts; white throat patch; no white in wings or tail. Sexes similar with slight pattern …
About These Birds
Sickle-winged Nightjar
A small Caprimulgidae nightjar (~44 g) of wet pampa grassland and marshes in southeastern South America. Males possess uniquely curved primary feathers creating a sickle-wing silhouette in flight. Inhabits dense grass over moist soils. Feeds on insects at dusk. Vulnerable from grassland drainage and conversion to cropland.
Spotted Nightjar
A medium Caprimulgidae nightjar (~103 g) of open woodland, spinifex grassland, and rocky ridges across mainland Australia. Intricately spotted and barred brown, grey, and buff. Cryptic by day on the ground among leaf litter. Crepuscular and nocturnal; feeds on flying insects caught in aerial pursuit. Least Concern.